Keith at 22:24 you say that the switch (2-3) on the motor starter is Normally Closed, that should be Normally Open. The Blue - Black wire on the motor starter are only connected when the coil is energized. Great diagrams, and good explanation. I had never looking into a motor starter before. It is really a latching relay with thermal overload protection. Understanding how it works is the way to go.
Thanks for taking the time to explain this I know you need them on a big motor but I never understood how to wire them or how they worked. Thanks again...
Up to my ears in that myself. I’m learning more about phase converters and motor starters than I ever wanted to know. However, it’s absolutely essential. Thanks, John
It probably should have been mentioned that there are different sizes of starters for different sizes of motors. One of yours was marked "Size 0" which is rated for up to 3 HP when operated at 230V (or 5HP at 460V). There is a smaller size, Size 00, good for up to 1.5HP at 230V as well as larger sizes up to Size 6 for a 200HP motor at 230V. You can find sizing charts online.
Serendipitously I discovered that by dragging the video slider back and forth you can animate Keith's switch drawings like a flip sheet. Some of the positions are a little obstructed but done on purpose I think this phenomenon could be used to great affect in future videos.
Great video I setup my air compressor roughly that way. No overload. Put a 3 phase (it's what I had on hand. Didn't need to be a 3 phase switch) magnetic switch in the 1 phase 220v line. To activate the switch I use a 110 wifi smart switch. Didn't want the compressor to have power on it when I wasn't home and manually tripping the breaker is impractical. So I walk in the shop and tell "Google to turn on compressor". Smart switch closes its contact witch sends 110v to the bigger switch with the 220v line and closes that contacts witch makes the compressor work normal as if it had power all the time. Saves money and I don't have to worry about the compressor contacts sticking closed with out me there. It has happened before..
I thought you said you were not an electrician. That was a good explanation. I am now working on an old industrial oven control that I plan to use for a foundry furnace. Circulator and exhaust fan, air flow switches, purge timer, flame sensor, pilot light, ignition and main gas. Lots of interlocks, timers and motor starters.
I've got an old HUGE (200LB) Baldor Bench Grinder at a factory maint. shop auction that had the push button start/stop but was removed by an idiot. I had the bits n pieces but could never figure out the wiring! THIS VIDEO WILL HELP GET IT UP AND RUNNING FINALLY!!!!!
The schematics for this circuit are all over the net. But try to find schematics for a latching circuit where the coil and load voltage are different. The only one of those you'll find is the one I posted. Because I looked for one. For like 3 days. Then I gave up and just made my own. Which I then decided to post for the next poor fool that might need it.
@@melgross if you think there is a mechanical latch then you did not get it. What latches this circuit is how it is wired. The start button energizes the coil and pulls the relay on. Once it is on switched power from the load side keeps the coil on. Then what you do with the start button does not matter. But when you hit stop that cuts power to the coil which opens the relay. Cutting power to the whole circuit turns it off too. And when it gets powered back up it will be in the off state. There's no mechanical latch whatsoever. That would defeat the purpose of this circuit. Well, one purpose. The other purpose is to make it easier to put on and off switches where they can be used.
@@1pcfred So if you only want a momentary on, you would disconnect the power lead from the load side to the coil? I wish he had explained how to install a momentary switch,such as a foot switch. Better yet, a way to have a momentary (bump) switch and a latching switch.
Good explanation! One comment regarding the "protector"... A 3 phase motor will burn up if it looses any ONE of the three phases. (The other 2 wires draw massive current) Hence, the motor-protector is intended to trip when a single phase is lost. (again...because the other 2 phases will draw excessive current)
Yes, that's the main reason i always use those (in Europe almost all industrial motors are 3 phase because of the 380/400V system, in most countries here, with one or two exeptions, like Norway, it is super expensive to use high current, but one allredy hawe "free" extra volts in the domestic lines in many countries (except for coutries that are for some reson using divided phase systems for the domestic lines, like Holland)), another thing in Europe is that many people does not seem to know about how important it is to newer ever run a 3 phase motor with Y-D connection in Y (star) moder for longer periods under load since that will also result in the coils runs extremly hot (unless the motor is especialy built to be run that way). Most old industrial systems here are using manual Y-D switching, but the modern systems are using automatic switching. (I think You will hawe 220V in America with the centerzero system, wich is the old domestic standard (outside the UK 240V centerfuse system) for countries wich are using the regular 3 phase 280V phase system. (today it is for some reason 230 and 400V after the EU standard))
Our 3 phase reticulation pump was manually started and stopped. Occasionally the protection circuits in the switch used to burn out, so our electrician connected 95 to A1 (same as on your diagram), protecting the protection device. Following this, the motor burned out a couple of times. Further investigation revealed that one of the phases had an intermittent poor connection. We learned that an important function of the protection circuit is to cut power on all phases if the current on one phase reduces or stops.
In the video at 5:27 when you are explaining how the motor starter works you said that normally the circuit is closed actually the circuit is normally open until the coil is energized. Great video though keep up the good work !
An interesting aside, for fractional or small HP motors, Shop Fox makes a paddle type on off switch that has a coil and contacts in it and functions like a magnetic starter but without the overload protection. Grizzly sells this switch in both a 120v and 240v version (110v-220v) but makes no reference to the relay. And like the magnetic starter, if the switch looses power, the contacts open and the motor will not automatically restart when the power is restored. And it is like $15.00 if I recall correctly.
There is one important aspect of using a starter that wasn’t mentioned: current. The motor needs LOTS of it, and contacts in the starter are huge so they can handle it. The coil that’s turned on and off by the remote switch is very low power, and the remote switch can have small, convenient contacts. It’s a very small power controlling a very large power. If you wanted to use a switch directly on the motor, it would have to be huge.
One of my mills has ancient DC motor controlled by a 1945 SquareD starter. It controls the startup inrush current via a dashpot and three resistor banks. It had been miss-wired and one of the internal straps was missing. If the schematic and care instructions weren't on the inside of the cover, I would have been out of luck. It works correctly now.
Even the way Keith draws the electrical diagrams is vintage. We haven’t used those little half circle bridges where wires intersect for 40 years. Since then the wires just cross each other, and when they connect, there’s a dot where the wires are crossing, to designate that they’re connected. Sometimes that aux switch that’s normally off, is used for a brake.
Dear Sir, Thank you very much for your time and you help me how to connect the motor. Can you explain how to connect booster switch to solar hot water heater system?
Keith, I may have missed it, but in your explanation, I didn't hear you mention that the remote start/stop switch can be utilized with a "pilot" voltage, entirely different from the starter internal line voltage, and, in fact, that is most often the case. Regardless of the size of the starter (which is sized so that the contacts can handle the full line voltage), the holding coil can be replaced, allowing the use of a 120/3/60, external "pilot" circuit to energize. Why would you do that? Usually, it's to save money on wiring to the on/off switch, and the added additional safety of a lower voltage circuit. In my professional life as an industrial air compressor sales engineer, I sold literally hundreds of air compressors in the 5HP to 25HP range, and I'd estimate that 75% of them used 120v control voltage if the line voltage was anything other than 120/1/60.
So are these what helps to not overload your grid when starting a 3 phase motor? As 3 phase motors don't have condensers like split phase does to help start them,?
Thankfully Keith qualified his motor starter tutorial by admitting that he is not an electrician. I quit counting the errors that he stated and demonstrated, because I quickly ran out of fingers! On the otherhand, if you can cypher through the misuse of terminology, electrical physics and misunderstanding of overload and over current his explanation is acceptable. Follow his electrical drawings and be less generous in accepting all of his descriptive dialog. He has the functinal gyst for the novice, but he included a lot of misinformation. Keith is obviously very accomplished. He regularly tackles work that I don't try. Kudos to Keith for getting it done, but I think that he should let this topic be handled by others that won't convey so much misinformation.
Lots of reasons, but one important one is that if power is lost, with these, the machine won't just come back on (possibly unattended) when the power comes back on. It defaults to being off and only routes power to the machine when the On switch is momentarily being pressed.
Keith I need to wire in a remote start/stop on a 110v single phase motor starter. Would the wiring be any different? Your schematic confuses me as being single phase, I have no connections at L2
Keith, You don’t mention another function of a motor starter. It provides a no-Volt release so that if the supply fails it will turn off and so when the power is restored the machine will not start unexpectedly. In the UK start buttons are normally slightly recessed so they are difficult to press accidentally while stop buttons have a large mushroom head so are easy to hit quickly in an emergency. Is it not the same over there?
I believe they also save or limit the need for heavy cable to a switch and preventing all three Lines having to go to an on/off switch. High voltage is more dangerous no question so this starter idea only uses one L vs. 3. I think its mostly about electricity safety and user safety plus the magnetic starter fully engages the circuit efficiently vs. a manual switch could engage the circuit slowly causing arcing and heat depending on the operator working the switch. These typically get invented due to hazard and safety concerns over the years.
Usually L1 L2 L 3 has 130 volts going thru them coils usually only need 24 volts and push buttons so wouldn't hooking the switch to L1 be to much or the auxiliary contact
Hello Keith, great vid., but having trouble w/Oliver 299D planer. It had a 400v. AB starter. I have rewired motors for 240 and bought a 509 B0D. As you know the planer has 2 motors an seperate switches for feed/cutter head. Would like to connect w/you thru VM website as I am also a member. TY
Something that may be outside the scope of this tutorial is that you can have different voltage coils, 240V, 120V or even 24V low voltage. Your illustration is for a 240V coil but the wiring will be different for other voltages.
I've seen modern power installations use 24v as a control voltage for switchgear. It would be simple if a 1:10 transformer could be used if the relay coil is AC.
@@ianhelsbyservices I wired up a motor using 24V relay coils and I just added another relay to get around the coil load voltage mismatch. It was what I had to work with. I wasn't about to go out and buy something else either. Not when I had a whole box of relays just begging to get used for something. I looked for the circuit online and couldn't find one. So I just figured it out for myself. I thought at the outset that doing what I wanted to do would be commonplace. Seemed like it'd be a common problem. The circuit here is great if you have the right contactor.
If the service factor of the motor is 1.15 or greater the overload or heater on the starter needs to be set or sized at 125% of the Full Load Amps or current, FLA and or FLC.
@@dimtt2 True. Since this is 3-phase, can two of the live wires be shorted out? I had thought only when the sine waves are exactly 180 degrees apart would they cancel each other.
It probably go to far for this video, but often this kind start systems (for heavy equipment) are combined wit star/delta systems to reduce inrush current. There are many explanation video’s on UA-cam.
The white starter that you refer to as a new style is an IEC style and has been a around for for a long time in other parts of the world. The Square D and Allen Bradly starters are know as NEMA style. NEMA style starters are created in the US and almost exclusively used in US. Good explanation though.
Is it worth putting a Variable frequency drive on a synchronous or asynchronous motor? Should the VFD be only used with a servo type motor? Example lathe drive motor with no gears(VFD servo)
The only thing that you left out of your control system is the fuses that protect your control circuits. When you leave L1 and L2 you need fuses. You should have no more than a 2 amp fuse for up to 1-3 small starters. If not the small controll wire is protected by the same breaker that is feeding your starter. Unless you have a control transformer sized for your control system then your transformer needs fuse protection. If something happens to your wiring or your start stop station gets damaged it could be bad.
I wired one up once with a fan to cool the motor. I had to pop the fan the motor had off for clearance. So I just put an external fan on the other side of the motor. When you hit start the motor runs and the fan runs. It's been working for years.
Motor starter? I thought they were called relays or contactors. Different strokes I guess. I note that you do call them contactors at some part of your video. Fuses/Circuit breakers are there to protect the wiring in the event of a fault in the equipment. They are not there to protect a motor (or load). If your motor is drawing too much current, it is faulty. If the circuit breaker is not rated correctly for the wiring, you will cause a fire if there is a fault. In regard to your diagrams and L1, L2, L3; I assume one of those is the neutral?? Very good explanation overall.
Generally home shop 3 phase is two hot single phase legs from the public utility and a 3rd leg generated by a phase converter, these days one of the incoming legs from the utility transformer is neutral but I have run in to exceptions.
The breaker at the breaker panel is sized to protect the wiring. The overload/heater system on the motor starter is to protect the motor. Example: Let's say you are running a shaper or planer and the tool digs in too deep and causes the ram to stop suddenly which in turn stops the motor suddenly, the heaters on the starter will trip before the circuit breaker and will prevent the motor from overheating. The heaters on the motor starter are more sensitive than breakers in a breaker panel, not to mention that the heaters help protect the contacts in the contactor portion of the motor starter. Modern motor starters have an adjustment to set the maximum safe current limit, the older starts require changing the value of the heater to get the right current limit. The motor does not have to be faulty to trip the overload/heater circuit. The reason it's called a motor starter is to let you know that it's not just a standard contactor. Yes, it is a contactor but it also has a set of side contacts to electrically hold the contactor in the ON position when the start button is released. And a 3 phase motor cannot run properly with a neutral as one of the legs, it has to be 3 equal voltage lines for 3 phase. Hope this helps to clear up some confusion :-)
Bizarrely, my milling machine does not have the 'no volt release' safety feature on any of the three motors. I'll add one when I get to installing a power supply to the garage !
I just mounted a loose box (with cable holders) on an extension of the connector cable for my workshop beltgrinder i made from a brooken piece of industrial extension cable and hanged it on a hook on the wall, the on/off buttons are on the machine so they are esy to reach, i also hawe a simple emergency push break on the machine.
"I am not an electrician! Let me put this first and foremost, I am NOT an electrician." **Electricians go to his site to learn about motors** How do I know? I'm an electrician and another electrician sent me this video.
I believe you pitched this one too low on the audience knowledge scale. I was interested in how this sort of thing worked, but not a basic lesson on Ohms law. Presumably there are even more safe and sophisticated systems featuring low voltage or even RF controls.
You may be right, but think about the noob who just finds a UA-cam video that skips the basics, then noob wires up a motor starter in the wrong way, and Bad Things Happen. I appreciate Keith taking the time to go all the way up from the basics. PS For noobs and time-served machinists alike: if you're unsure what you're doing with electrics, put down the tools and study until you are certain, or get help!
Brace yourself... All the elechickens coming! They will be posting all the reasons why you are wrong because you are not using low voltage for the start stop switch circuits
Good Job ! Both the IEC (your "new style") and NEMA (your "old style") starters have extra Aux contact for alarming, signaling, or whatever you need for your control. In the heavy duty industrial applications I was involved with, we used NEMA due to them being oversized and their ability to withstand multiple overload conditions without damage.
Nicely done Keith. Having worked in a shop before I wired up a few machines with the electricians. This was when I was about 18~19, so I was just learning stuff. You did a much better job of explaining it than they did. They were more "yea, just wire it like this". I was "WHY!?!", they were "Because it will work this way". I kind of wondered if they actually knew...LOL
@@sixonegfour2719 honestly? I was 18. How much did I know then. My uncle was a master electrician and taught me a few things. I know enough to know when I need help that's for sure. I also have a brother in law who is a master electrician, so I got that going for me. Lol
Motors need to be “over fused” because they take large amounts of current to start, but they also need to be protected from long term overload during use. The “heater” over current device builds slowly (relatively) and accepts the high inrush of current during starting from a stoped rotor but will trip if a motor is drawing much lower current (relative to the brief starting current) that is higher than its rating. AND: series all your STOP buttons, and parallel all your START buttons if you have more than one start/stop station.
If one opts to use a static phase converter, make sure you read/understand the instructions! I was able to get a used Ronk static converter at a really good price. One thing the paperwork emphasizes is that nothing except the motor itself gets connected to the created/generated leg. I had to trace out, and sometimes move, wiring on my controls and relays, in order to use the converter on my surface grinder. Another item is that the converter must be tuned to the machine, or you risk overheating and damaging your motor. If you can't get, follow, understand the instructions to your particular converter ... get help! Statics are not "plug and play." Especially on a machine that was previously used in a shop that had commercial 3 phase power.
Keith, thanks for a great explanation of how all this stuff works. I agree that it's really important for those of us "playing" with older machines to understand how things work and not just try to get by with "connect terminal a to terminal b, then c to d" style of working. When you understand how it all works, you can confirm for yourself what will happen when the power goes out or there is an overload. If you don't understand how something works you really don't know if it's safe (electrical or otherwise). This is not easy to explain and I think you did a great job. BTW, for those accomplishing the same task with a VFD, things are done a little differently, but all the same safety considerations need to be taken into account.
excellent video and exactly what I needed thank you so very much... but sadly I have adult severe ADHD and I'm going to have to watch the video 50 times to completely get it
ARE YOU STILL AROUND????QUESTION?? ON THE 2ND MAGNETIC STARTER WHERE??? DO YOU PUT A GROUND WIRE??? ALL OUR OLD STARTERS HAVE NO GROUND IN IT ?? FOR THE MOTOR THERE IS A SHORT GROUND GOING FROM MOTOR CONNECTION BOX TO THE CEMENT WALL ANCHOR IN 4BY 4 BOX ON WALL.. BUT FOR THE IN COMING POWER FROM.BUSS SWITCH NO GROUND CAN ONE BE ATTATCHED TO WALL ON THE ON OFF BUTTONS??
Very nice, Keith, but typically 14:00 start is NO and stop is NC 😉 Which you stated correctly at 14:12 Folks should keep in mind pressing the stop button interrupts the circuit, just like the overload does. And, and, you can have multiple stop switches wired in series with that one stop switch. Multiple stop switches are handy on a large machine if the operator may step away from the main control area (hint 😉)
Another use for Motor Starter Type Switching is to protect Electronics. It shuts off the Ckt at the Hint of brown outs or Flickering Power, Like Auto reset Power line breakers and they Stay off till You deem it safe to turn them back on. I have made a few with just an Ice Cube Continuous Duty 10 Amp relay, Nc & No buttons. Then I plug a UPS into those if Needed.
Maybe you can help me diagnose a problem with a starter. I've got a step down transformer going from 480-120 to run my coil. I had the transformer on the shelf, and didn't want to order a new coil for 480v. Anyhow, my start and stop buttons work fine, however, if i manually actuate the contactor, the coil becomes energized and the contactor stays closed. I've never experienced this before. Any insight?
That was a good explanation of a contactor circuit with overload protection. One option that I have encountered on our heavy duty 480 volt pressure washers at work, is a rotary on/off switch in lieu of push buttons which I do not care for. Our equipment has a time delay in the lock circuit that won't operate unless there is water pressure present at the pump. It's just a more complicated circuit. There's a good possibility that the machine could be turned on when a power disruption is resolved. I hope in your next installment on this machine that when you begin to discuss wiring it up that you can discuss horsepower amperage draw in relation to wire gauge, and phase rotation, which can be changed from changing any two legs of the 3 phase motor in one of 4 places. It can be done on L1, 2, 3, on the contactor or on t1, 2, 3 of the same. It can be done on the electrical breakers, or in the event of a plug, it could also be done at this point. Again, thanks for the well thought out discussion on this safety feature. On further point I would suggest is that if/when this shaper is plugged in, that the breaker or disconnect box be turned off before plugging it in as high voltage does have a risk of arcing when plugging in, even with a contactor deactivated. The company that we contract with has made this a work rule.
Keith at 22:24 you say that the switch (2-3) on the motor starter is Normally Closed, that should be Normally Open. The Blue - Black wire on the motor starter are only connected when the coil is energized.
Great diagrams, and good explanation. I had never looking into a motor starter before. It is really a latching relay with thermal overload protection. Understanding how it works is the way to go.
Well explained I have been an electrician for 50 years , that explains things very succinctly.
Thanks for taking the time to explain this I know you need them on a big motor but I never understood how to wire them or how they worked. Thanks again...
Awesome great way to start my morning . Thank you Keith for the wonderful videos explaining how to do things !
Up to my ears in that myself. I’m learning more about phase converters and motor starters than I ever wanted to know.
However, it’s absolutely essential.
Thanks,
John
Great video Keith! You've demystified motor starters and stop-start pushbuttons for me!
Thank goodness for instructions that come with switches. I do this type of thing so infrequently I have to relearn it each time. Thanks for the video.
It probably should have been mentioned that there are different sizes of starters for different sizes of motors. One of yours was marked "Size 0" which is rated for up to 3 HP when operated at 230V (or 5HP at 460V). There is a smaller size, Size 00, good for up to 1.5HP at 230V as well as larger sizes up to Size 6 for a 200HP motor at 230V. You can find sizing charts online.
Serendipitously I discovered that by dragging the video slider back and forth you can animate Keith's switch drawings like a flip sheet. Some of the positions are a little obstructed but done on purpose I think this phenomenon could be used to great affect in future videos.
Great video
I setup my air compressor roughly that way. No overload.
Put a 3 phase (it's what I had on hand. Didn't need to be a 3 phase switch) magnetic switch in the 1 phase 220v line. To activate the switch I use a 110 wifi smart switch. Didn't want the compressor to have power on it when I wasn't home and manually tripping the breaker is impractical. So I walk in the shop and tell "Google to turn on compressor". Smart switch closes its contact witch sends 110v to the bigger switch with the 220v line and closes that contacts witch makes the compressor work normal as if it had power all the time. Saves money and I don't have to worry about the compressor contacts sticking closed with out me there. It has happened before..
My god man....your workshop looks absolutely fantastic. 👀👀
I thought you said you were not an electrician. That was a good explanation. I am now working on an old industrial oven control that I plan to use for a foundry furnace. Circulator and exhaust fan, air flow switches, purge timer, flame sensor, pilot light, ignition and main gas. Lots of interlocks, timers and motor starters.
I've got an old HUGE (200LB) Baldor Bench Grinder at a factory maint. shop auction that had the push button start/stop but was removed by an idiot. I had the bits n pieces but could never figure out the wiring! THIS VIDEO WILL HELP GET IT UP AND RUNNING FINALLY!!!!!
The schematics for this circuit are all over the net. But try to find schematics for a latching circuit where the coil and load voltage are different. The only one of those you'll find is the one I posted. Because I looked for one. For like 3 days. Then I gave up and just made my own. Which I then decided to post for the next poor fool that might need it.
For reference. This is called a "3-wire start/stop" and the type of circuit is called a latching circuit. Very well explained Keith!
Yes. Latching. Without that explanation, it makes no sense. A mechanical “latch” that holds the circuit closed.
@@melgross if you think there is a mechanical latch then you did not get it. What latches this circuit is how it is wired. The start button energizes the coil and pulls the relay on. Once it is on switched power from the load side keeps the coil on. Then what you do with the start button does not matter. But when you hit stop that cuts power to the coil which opens the relay. Cutting power to the whole circuit turns it off too. And when it gets powered back up it will be in the off state. There's no mechanical latch whatsoever. That would defeat the purpose of this circuit. Well, one purpose. The other purpose is to make it easier to put on and off switches where they can be used.
@@1pcfred there are numerous ways to do this. I’ve designed a few myself. Sure, there are electrical and mechanical latching relays.
@@melgross you are not going to find mechanical latching relays in this application. Unless you buy your gear off sadists.
@@1pcfred So if you only want a momentary on, you would disconnect the power lead from the load side to the coil? I wish he had explained how to install a momentary switch,such as a foot switch. Better yet, a way to have a momentary (bump) switch and a latching switch.
Great video simplified for beginners in control power. Thank you
Well done Keith, thanks for taking the time so it could sink in.
Good explanation! One comment regarding the "protector"... A 3 phase motor will burn up if it looses any ONE of the three phases. (The other 2 wires draw massive current) Hence, the motor-protector is intended to trip when a single phase is lost. (again...because the other 2 phases will draw excessive current)
Yes, that's the main reason i always use those (in Europe almost all industrial motors are 3 phase because of the 380/400V system, in most countries here, with one or two exeptions, like Norway, it is super expensive to use high current, but one allredy hawe "free" extra volts in the domestic lines in many countries (except for coutries that are for some reson using divided phase systems for the domestic lines, like Holland)), another thing in Europe is that many people does not seem to know about how important it is to newer ever run a 3 phase motor with Y-D connection in Y (star) moder for longer periods under load since that will also result in the coils runs extremly hot (unless the motor is especialy built to be run that way). Most old industrial systems here are using manual Y-D switching, but the modern systems are using automatic switching.
(I think You will hawe 220V in America with the centerzero system, wich is the old domestic standard (outside the UK 240V centerfuse system) for countries wich are using the regular 3 phase 280V phase system. (today it is for some reason 230 and 400V after the EU standard))
Our 3 phase reticulation pump was manually started and stopped. Occasionally the protection circuits in the switch used to burn out, so our electrician connected 95 to A1 (same as on your diagram), protecting the protection device. Following this, the motor burned out a couple of times. Further investigation revealed that one of the phases had an intermittent poor connection. We learned that an important function of the protection circuit is to cut power on all phases if the current on one phase reduces or stops.
Excellent video Keith.
Thanks for sharing this Keith. Very well explained and simplified
In the video at 5:27 when you are explaining how the motor starter works you said that normally the circuit is closed actually the circuit is normally open until the coil is energized. Great video though keep up the good work !
That was great. Very informative and useful! Thanks, Keith.
An interesting aside, for fractional or small HP motors, Shop Fox makes a paddle type on off switch that has a coil and contacts in it and functions like a magnetic starter but without the overload protection. Grizzly sells this switch in both a 120v and 240v version (110v-220v) but makes no reference to the relay.
And like the magnetic starter, if the switch looses power, the contacts open and the motor will not automatically restart when the power is restored. And it is like $15.00 if I recall correctly.
Keith this was a great video. You explained everything very well. Do you have any videos on wiring up and changing voltages on a transformer.
Excellent video....clear explanations of the circuits.
I liked the way you teach
There is one important aspect of using a starter that wasn’t mentioned: current. The motor needs LOTS of it, and contacts in the starter are huge so they can handle it. The coil that’s turned on and off by the remote switch is very low power, and the remote switch can have small, convenient contacts. It’s a very small power controlling a very large power. If you wanted to use a switch directly on the motor, it would have to be huge.
He very clearly spoke about amperage (current).
Very well done. I teach this at a votech and I may use this in my class thank you
Great job Mr. Rucker!
thanks keith, it's a tricky concept and that video is going to help a lot of us.
One of my mills has ancient DC motor controlled by a 1945 SquareD starter. It controls the startup inrush current via a dashpot and three resistor banks. It had been miss-wired and one of the internal straps was missing. If the schematic and care instructions weren't on the inside of the cover, I would have been out of luck. It works correctly now.
Even the way Keith draws the electrical diagrams is vintage. We haven’t used those little half circle bridges where wires intersect for 40 years. Since then the wires just cross each other, and when they connect, there’s a dot where the wires are crossing, to designate that they’re connected.
Sometimes that aux switch that’s normally off, is used for a brake.
Thank you for sharing. Enjoyed.
Thanks Keith answered alot of questions.
Dear Sir,
Thank you very much for your time and you help me how to connect the motor.
Can you explain how to connect booster switch to solar hot water heater system?
Good job of explaining mag starters. You are so right - understanding the principles behind starters are a powerful tool to have.
Thank so much for good explanation
Great video. Thank you
Great job Keith, useful video
Great job Keith.
Great job
Great explanation.
Sure would have been nice to see that square d switch hooked up also though, since that's the one I have, but great video...
Great job Keith 👏 👍
Keith, I may have missed it, but in your explanation, I didn't hear you mention that the remote start/stop switch can be utilized with a "pilot" voltage, entirely different from the starter internal line voltage, and, in fact, that is most often the case. Regardless of the size of the starter (which is sized so that the contacts can handle the full line voltage), the holding coil can be replaced, allowing the use of a 120/3/60, external "pilot" circuit to energize. Why would you do that? Usually, it's to save money on wiring to the on/off switch, and the added additional safety of a lower voltage circuit. In my professional life as an industrial air compressor sales engineer, I sold literally hundreds of air compressors in the 5HP to 25HP range, and I'd estimate that 75% of them used 120v control voltage if the line voltage was anything other than 120/1/60.
So are these what helps to not overload your grid when starting a 3 phase motor? As 3 phase motors don't have condensers like split phase does to help start them,?
Thankfully Keith qualified his motor starter tutorial by admitting that he is not an electrician.
I quit counting the errors that he stated and demonstrated, because I quickly ran out of fingers!
On the otherhand, if you can cypher through the misuse of terminology, electrical physics and misunderstanding of overload and over current his explanation is acceptable. Follow his electrical drawings and be less generous in accepting all of his descriptive dialog. He has the functinal gyst for the novice, but he included a lot of misinformation.
Keith is obviously very accomplished. He regularly tackles work that I don't try. Kudos to Keith for getting it done, but I think that he should let this topic be handled by others that won't convey so much misinformation.
Great info thank you.
Great explanation!
I never thought about these switches. Great video. Question: why don’t they use a simple on/off light switch?
Lots of reasons, but one important one is that if power is lost, with these, the machine won't just come back on (possibly unattended) when the power comes back on. It defaults to being off and only routes power to the machine when the On switch is momentarily being pressed.
Did Keith ever utilise light indicators on his compressor switchboard to know when it's powered or in an error state?
How new is the new mechanism? I have the new one on my 20yo Grizzly table saw.
Keith
I need to wire in a remote start/stop on a 110v single phase motor starter. Would the wiring be any different? Your schematic confuses me as being single phase, I have no connections at L2
Keith,
You don’t mention another function of a motor starter. It provides a no-Volt release so that if the supply fails it will turn off and so when the power is restored the machine will not start unexpectedly.
In the UK start buttons are normally slightly recessed so they are difficult to press accidentally while stop buttons have a large mushroom head so are easy to hit quickly in an emergency. Is it not the same over there?
(He actually does at end. Ugly scenario. Power fails. Decide to clean/adjust machine. Power restored.). Most important feature in my opinion.
@@robertbamford8266 the struggle with ADD is real.
I believe they also save or limit the need for heavy cable to a switch and preventing all three Lines having to go to an on/off switch. High voltage is more dangerous no question so this starter idea only uses one L vs. 3. I think its mostly about electricity safety and user safety plus the magnetic starter fully engages the circuit efficiently vs. a manual switch could engage the circuit slowly causing arcing and heat depending on the operator working the switch. These typically get invented due to hazard and safety concerns over the years.
Usually L1 L2 L 3 has 130 volts going thru them coils usually only need 24 volts and push buttons so wouldn't hooking the switch to L1 be to much or the auxiliary contact
Thanks Keith.
Hello Keith, great vid., but having trouble w/Oliver 299D planer.
It had a 400v. AB starter. I have rewired motors for 240 and bought a 509 B0D. As you know the planer has 2 motors an seperate switches for feed/cutter head. Would like to connect w/you thru VM website as I am also a member. TY
what model push button starter are you using Dayton 20c794?
Something that may be outside the scope of this tutorial is that you can have different voltage coils, 240V, 120V or even 24V low voltage. Your illustration is for a 240V coil but the wiring will be different for other voltages.
I've seen modern power installations use 24v as a control voltage for switchgear. It would be simple if a 1:10 transformer could be used if the relay coil is AC.
@@ianhelsbyservices I wired up a motor using 24V relay coils and I just added another relay to get around the coil load voltage mismatch. It was what I had to work with. I wasn't about to go out and buy something else either. Not when I had a whole box of relays just begging to get used for something. I looked for the circuit online and couldn't find one. So I just figured it out for myself. I thought at the outset that doing what I wanted to do would be commonplace. Seemed like it'd be a common problem. The circuit here is great if you have the right contactor.
Ok, I get it now. If we see the back of Keith's hand, the circuit is energized.
Keith, you're a fuckin G my man!
Im getting lost on the black and blue wire could you explain it more
Hiya Keith
If the service factor of the motor is 1.15 or greater the overload or heater on the starter needs to be set or sized at 125% of the Full Load Amps or current, FLA and or FLC.
Based on the circuit diagram, when you hit the START switch, aren't you shorting L1 and L2 together? Is that normal?
You are not shorting them, the coil is the load for that circuit.
@@dimtt2 True. Since this is 3-phase, can two of the live wires be shorted out? I had thought only when the sine waves are exactly 180 degrees apart would they cancel each other.
It probably go to far for this video, but often this kind start systems (for heavy equipment) are combined wit star/delta systems to reduce inrush current. There are many explanation video’s on UA-cam.
The white starter that you refer to as a new style is an IEC style and has been a around for for a long time in other parts of the world. The Square D and Allen Bradly starters are know as NEMA style. NEMA style starters are created in the US and almost exclusively used in US. Good explanation though.
Where is your neutral? Line 2 is going through your overload straight to your coil as well as your line one
Is it worth putting a Variable frequency drive on a synchronous or asynchronous motor? Should the VFD be only used with a servo type motor? Example lathe drive motor with no gears(VFD servo)
Possibly, if the motor is strong enough at lower speeds. Mine was way too small.
Thanks. While I've followed directions, I really didn't visualize what was happening.
The only thing that you left out of your control system is the fuses that protect your control circuits. When you leave L1 and L2 you need fuses. You should have no more than a 2 amp fuse for up to 1-3 small starters. If not the small controll wire is protected by the same breaker that is feeding your starter. Unless you have a control transformer sized for your control system then your transformer needs fuse protection. If something happens to your wiring or your start stop station gets damaged it could be bad.
Can use the aux for lights! And or an coolant pump
I wired one up once with a fan to cool the motor. I had to pop the fan the motor had off for clearance. So I just put an external fan on the other side of the motor. When you hit start the motor runs and the fan runs. It's been working for years.
In Europe, the coli is switched between L1 and neutral, which is 220 to 240 Volt. Otherwise the same.
and a fuse is also used between L1 and the stop button
Life saver
Jolly Rancher
There are also solid state contactors--no moving/mechanical parts and quiet.
At 3:50 you said the circuit is open = no voltage can go through.
But then at 5:26 you say it’s closed = no voltage can go through
Very confusing
Motor starter? I thought they were called relays or contactors. Different strokes I guess. I note that you do call them contactors at some part of your video.
Fuses/Circuit breakers are there to protect the wiring in the event of a fault in the equipment. They are not there to protect a motor (or load). If your motor is drawing too much current, it is faulty. If the circuit breaker is not rated correctly for the wiring, you will cause a fire if there is a fault.
In regard to your diagrams and L1, L2, L3; I assume one of those is the neutral??
Very good explanation overall.
Generally home shop 3 phase is two hot single phase legs from the public utility and a 3rd leg generated by a phase converter, these days one of the incoming legs from the utility transformer is neutral but I have run in to exceptions.
@m9 ovich That's if the load is wired delta, if its wired as wye you have a neutral at the junction of the three fields.
Motor starters have overloads Contactors do not. That is how I was taught.
The breaker at the breaker panel is sized to protect the wiring.
The overload/heater system on the motor starter is to protect the motor. Example: Let's say you are running a shaper or planer and the tool digs in too deep and causes the ram to stop suddenly which in turn stops the motor suddenly, the heaters on the starter will trip before the circuit breaker and will prevent the motor from overheating.
The heaters on the motor starter are more sensitive than breakers in a breaker panel, not to mention that the heaters help protect the contacts in the contactor portion of the motor starter.
Modern motor starters have an adjustment to set the maximum safe current limit, the older starts require changing the value of the heater to get the right current limit.
The motor does not have to be faulty to trip the overload/heater circuit.
The reason it's called a motor starter is to let you know that it's not just a standard contactor. Yes, it is a contactor but it also has a set of side contacts to electrically hold the contactor in the ON position when the start button is released.
And a 3 phase motor cannot run properly with a neutral as one of the legs, it has to be 3 equal voltage lines for 3 phase.
Hope this helps to clear up some confusion :-)
@m9 ovich Control is just an illusion.
GREAT TO KNOW, GREAT JOB, GREAT VIDEO, TELL THE DOGS & CATS HELLO, [ BACK TO WORK ]...
Can anyone guide me how yo rewire up a polishing moto
hands in front of meter such that the readout may not be seen.
Bizarrely, my milling machine does not have the 'no volt release' safety feature on any of the three motors. I'll add one when I get to installing a power supply to the garage !
I just mounted a loose box (with cable holders) on an extension of the connector cable for my workshop beltgrinder i made from a brooken piece of industrial extension cable and hanged it on a hook on the wall, the on/off buttons are on the machine so they are esy to reach, i also hawe a simple emergency push break on the machine.
"I am not an electrician! Let me put this first and foremost, I am NOT an electrician."
**Electricians go to his site to learn about motors**
How do I know? I'm an electrician and another electrician sent me this video.
I believe you pitched this one too low on the audience knowledge scale. I was interested in how this sort of thing worked, but not a basic lesson on Ohms law.
Presumably there are even more safe and sophisticated systems featuring low voltage or even RF controls.
You may be right, but think about the noob who just finds a UA-cam video that skips the basics, then noob wires up a motor starter in the wrong way, and Bad Things Happen. I appreciate Keith taking the time to go all the way up from the basics.
PS For noobs and time-served machinists alike: if you're unsure what you're doing with electrics, put down the tools and study until you are certain, or get help!
Brace yourself... All the elechickens coming!
They will be posting all the reasons why you are wrong because you are not using low voltage for the start stop switch circuits
That was me, 40 years ago.
If u are not an electrician.u probably don't need to be putting this information out there. This stuff can can be kill a person. Respectfully.
Your grammar can be kill a person. Respectfully.
Good Job !
Both the IEC (your "new style") and NEMA (your "old style") starters have extra Aux contact for alarming, signaling, or whatever you need for your control. In the heavy duty industrial applications I was involved with, we used NEMA due to them being oversized and their ability to withstand multiple overload conditions without damage.
Nicely done Keith. Having worked in a shop before I wired up a few machines with the electricians. This was when I was about 18~19, so I was just learning stuff. You did a much better job of explaining it than they did. They were more "yea, just wire it like this". I was "WHY!?!", they were "Because it will work this way". I kind of wondered if they actually knew...LOL
Truly sounds like majority of electricians unfortunately.
@@sixonegfour2719 honestly? I was 18. How much did I know then. My uncle was a master electrician and taught me a few things. I know enough to know when I need help that's for sure. I also have a brother in law who is a master electrician, so I got that going for me. Lol
Motors need to be “over fused” because they take large amounts of current to start, but they also need to be protected from long term overload during use. The “heater” over current device builds slowly (relatively) and accepts the high inrush of current during starting from a stoped rotor but will trip if a motor is drawing much lower current (relative to the brief starting current) that is higher than its rating.
AND: series all your STOP buttons, and parallel all your START buttons if you have more than one start/stop station.
If one opts to use a static phase converter, make sure you read/understand the instructions!
I was able to get a used Ronk static converter at a really good price. One thing the paperwork emphasizes is that nothing except the motor itself gets connected to the created/generated leg. I had to trace out, and sometimes move, wiring on my controls and relays, in order to use the converter on my surface grinder.
Another item is that the converter must be tuned to the machine, or you risk overheating and damaging your motor.
If you can't get, follow, understand the instructions to your particular converter ... get help! Statics are not "plug and play." Especially on a machine that was previously used in a shop that had commercial 3 phase power.
Guessing we will be seeing a video on the metal planer motor starter soon 😊
Keith, thanks for a great explanation of how all this stuff works. I agree that it's really important for those of us "playing" with older machines to understand how things work and not just try to get by with "connect terminal a to terminal b, then c to d" style of working. When you understand how it all works, you can confirm for yourself what will happen when the power goes out or there is an overload. If you don't understand how something works you really don't know if it's safe (electrical or otherwise). This is not easy to explain and I think you did a great job. BTW, for those accomplishing the same task with a VFD, things are done a little differently, but all the same safety considerations need to be taken into account.
excellent video and exactly what I needed thank you so very much... but sadly I have adult severe ADHD and I'm going to have to watch the video 50 times to completely get it
I’m an industrial tech apprentice going through schooling, and I understood this explanation a lot better. Awesome job thank you!
ARE YOU STILL AROUND????QUESTION?? ON THE 2ND MAGNETIC STARTER WHERE??? DO YOU PUT A GROUND WIRE???
ALL OUR OLD STARTERS HAVE NO GROUND IN IT ?? FOR THE MOTOR THERE IS A SHORT GROUND GOING FROM MOTOR CONNECTION BOX TO THE CEMENT WALL ANCHOR IN 4BY 4 BOX ON WALL..
BUT FOR THE IN COMING POWER FROM.BUSS SWITCH NO GROUND CAN ONE BE ATTATCHED TO WALL ON THE ON OFF BUTTONS??
Very nice, Keith, but typically 14:00 start is NO and stop is NC 😉 Which you stated correctly at 14:12
Folks should keep in mind pressing the stop button interrupts the circuit, just like the overload does. And, and, you can have multiple stop switches wired in series with that one stop switch. Multiple stop switches are handy on a large machine if the operator may step away from the main control area (hint 😉)
Another use for Motor Starter Type Switching is to protect Electronics. It shuts off the Ckt at the Hint of brown outs or Flickering Power, Like Auto reset Power line breakers and they Stay off till You deem it safe to turn them back on.
I have made a few with just an Ice Cube Continuous Duty 10 Amp relay, Nc & No buttons.
Then I plug a UPS into those if Needed.
Maybe you can help me diagnose a problem with a starter. I've got a step down transformer going from 480-120 to run my coil. I had the transformer on the shelf, and didn't want to order a new coil for 480v. Anyhow, my start and stop buttons work fine, however, if i manually actuate the contactor, the coil becomes energized and the contactor stays closed. I've never experienced this before. Any insight?
Don't forget kieth .coils have different voltage ratings .and contactors have different current ratings .👍👍
That was a good explanation of a contactor circuit with overload protection. One option that I have encountered on our heavy duty 480 volt pressure washers at work, is a rotary on/off switch in lieu of push buttons which I do not care for. Our equipment has a time delay in the lock circuit that won't operate unless there is water pressure present at the pump. It's just a more complicated circuit. There's a good possibility that the machine could be turned on when a power disruption is resolved.
I hope in your next installment on this machine that when you begin to discuss wiring it up that you can discuss horsepower amperage draw in relation to wire gauge, and phase rotation, which can be changed from changing any two legs of the 3 phase motor in one of 4 places. It can be done on L1, 2, 3, on the contactor or on t1, 2, 3 of the same. It can be done on the electrical breakers, or in the event of a plug, it could also be done at this point.
Again, thanks for the well thought out discussion on this safety feature.
On further point I would suggest is that if/when this shaper is plugged in, that the breaker or disconnect box be turned off before plugging it in as high voltage does have a risk of arcing when plugging in, even with a contactor deactivated.
The company that we contract with has made this a work rule.