Just to correct a little bit, the LOR and the C coils are connected in series and there’s a voltage drop not and amp difference. The LOR is 12V and the C is 24v, since the LOR is taking away 12v out of the 24V source the C coil is only receiving 12v too not fully energizing it since it needs 24v thus not activating it.
I have been in and out of the the trade for years and even instructed before and have never seen a simpler explanation of the lockout system....Actually explained, so that others can understand....I will use this method, and again, I thank you sir for what you do....I wish I would have had you to learn from when I was struggling to learn the trade....The good thing is, I can still learn from you and so can others that want to know.
It took 2 listens to get it straight, but it's all there. Thank you for another lucid, helpful video! I think it would have helped it the watcher were told earlier "what" the Lockout Relay was for, and the proceed with "how" it does it.
Thank you Sir. You are awesome at what you do. We never stop learning and you just proved it. I never thought that one coil can override another and just use it as a pathway back to the transformer.
The important reason that the LOR picks and the contactor coil does not is that the LOR is a "high impendance relay," meaning that while it takes very little current to pick it up, its windings act as a limiting resistor in series with the contactor coil, so that the LOR itself prevents enough current from flowing to satisfy the contactor coil requirement for pickup current. The LOR impedance is many times that of the contactor coil, and the resistive component difference can be measured with a meter. This kind of circuit is used on all of those old York Sunline units with the small board at the top of the control bay.
I didn't understand why the lor is in serie with the CONTACTOR C. We can connect it directly to the negative ie in parallel with C and it will deenergize the C
The point of this circuit is to only deenergize the contactor if the limit or pressure switch open. When wired as you suggest, it would be deenergized whenever the thermostat closed. GFM
Ive Had issues with this where you have a fire relay on a A/C so when the fire guys or a false fire alarm sounded it would initiate my lockout relay...... This building had constanly had fire alarms going off which shut off the A/C... A reset would be the only way
Any way to check a lock out relay? I just changed out an ICM220. I want to check to see if I did the right thing. System started fine after I changed it but I want to be sure the LOR was bad
There is a good chance the LOR has not failed if the unit shut down on lockout. Under normal operation the relay does not energize. If there was, for example, a high head switch wired to the lockout, the unit would shut down and the high pressure would drop because the unit is not running. GFM
I try tht lock out relay with 2 compressor and with overload relay. The think is it will not work. Even the lockout relay is energize but if you removed the power of condenser fan motor and not connecting that time its work. That why im i confused and check again the wiring. When the lockout relay energize it must compressor and cond fan not working but still working so i check the power of compressor it show 8 volts lockout relay is 16 volts and condenser fan contactor 24 volts, what i did i removed the control for cond fan that time its workin fine. But i dont know what is the reason that's why im confused
If it was 120V not 24V would the compressor contactor coil get damaged in anyway when current passes through the LOR and then into the CCC when a safety is open ? so your saying voltage is being used up to activate the LOR and not enough to activate CCC ?
Brent Peluso In electricity, nothing is simple. What we may think of as always a no no, often works quite well in the right conditions. The lockout circuit is one of those. The more you learn about electricity, the more interesting it is. GFM
The electricity will travel thru the circuit that has the lowest resistance. The high resistance of the coil of the LOR relay precludes enough power traveling thru it to energize the coil. I know this is hard to understand, and I will try to do another video attempting to explain why the electricity does this. GFM
Don't use lockout on a WR 5400 thermostat if u have a packaged A/C & heat pump WATHER IT'S a GAS PACK or NOT cause it can make it not run right believe me I've had many problems a packaged unit from the year 2000 or older have built in lockout delay. For units 2001 and later do use the lockout feature on this thermostat they have an electronic lockout delay witch need this.
Just to correct a little bit, the LOR and the C coils are connected in series and there’s a voltage drop not and amp difference. The LOR is 12V and the C is 24v, since the LOR is taking away 12v out of the 24V source the C coil is only receiving 12v too not fully energizing it since it needs 24v thus not activating it.
I have been in and out of the the trade for years and even instructed before and have never seen a simpler explanation of the lockout system....Actually explained, so that others can understand....I will use this method, and again, I thank you sir for what you do....I wish I would have had you to learn from when I was struggling to learn the trade....The good thing is, I can still learn from you and so can others that want to know.
Glad I could help.
GFM
I never fully understood the way this worked until now thank you GFM for the videos, great stuff, helps with my self confidence in the field
Welcome
GFM
It took 2 listens to get it straight, but it's all there.
Thank you for another lucid, helpful video!
I think it would have helped it the watcher were told earlier "what" the Lockout Relay was for, and the proceed with "how" it does it.
Good thoughts
GFM
Thank you Sir. You are awesome at what you do. We never stop learning and you just proved it. I never thought that one coil can override another and just use it as a pathway back to the transformer.
Electricity surprises me every time.
GFM
Nice way of explaining it, was spinning my head around this. THANKS!
Welcome
GFM
The important reason that the LOR picks and the contactor coil does not is that the LOR is a "high impendance relay," meaning that while it takes very little current to pick it up, its windings act as a limiting resistor in series with the contactor coil, so that the LOR itself prevents enough current from flowing to satisfy the contactor coil requirement for pickup current. The LOR impedance is many times that of the contactor coil, and the resistive component difference can be measured with a meter. This kind of circuit is used on all of those old York Sunline units with the small board at the top of the control bay.
A million thanks for the video 😊
Wow... Great lecture 🔥
you do a better job explaining this, compared my professor. keep it up.
Thank you sir. I understand it now.
excellent video. you're the best one at explanation
Thanks for the support.
GFM
thanks, I have benefitted from your lectures
Welcome
GFM
THANKS! great video, very easy to understand.
Nice video
I didn't understand why the lor is in serie with the CONTACTOR C. We can connect it directly to the negative ie in parallel with C and it will deenergize the C
The point of this circuit is to only deenergize the contactor if the limit or pressure switch open.
When wired as you suggest, it would be deenergized whenever the thermostat closed.
GFM
You are the best 😍😍👍👍🙏🙏
Ive Had issues with this where you have a fire relay on a A/C so when the fire guys or a false fire alarm sounded it would initiate my lockout relay...... This building had constanly had fire alarms going off which shut off the A/C... A reset would be the only way
I have an spurious signal that make open the LOR, I think that replacing LOR by a LOR with 1 seg timer, It will be solve. Can you help me with this.
Great video
Any way to check a lock out relay? I just changed out an ICM220. I want to check to see if I did the right thing. System started fine after I changed it but I want to be sure the LOR was bad
There is a good chance the LOR has not failed if the unit shut down on lockout. Under normal operation the relay does not energize. If there was, for example, a high head switch wired to the lockout, the unit would shut down and the high pressure would drop because the unit is not running.
GFM
I try tht lock out relay with 2 compressor and with overload relay. The think is it will not work. Even the lockout relay is energize but if you removed the power of condenser fan motor and not connecting that time its work. That why im i confused and check again the wiring. When the lockout relay energize it must compressor and cond fan not working but still working so i check the power of compressor it show 8 volts lockout relay is 16 volts and condenser fan contactor 24 volts, what i did i removed the control for cond fan that time its workin fine. But i dont know what is the reason that's why im confused
Great video - TYSM for making and sharing.
Question: what software package do you use to make the circuit diagrams?
I actually do not use any. Just Keynote (Powerpoint to Microsoft users).
GFM
+grayfurnaceman
Great work!
You had me thinking it was some "interactive electric circuit" program :)
I found the programs to actually harder to use for simple diagrams like this.
GFM
good video.
If it was 120V not 24V would the compressor contactor coil get damaged in anyway when current passes through the LOR and then into the CCC when a safety is open ? so your saying voltage is being used up to activate the LOR and not enough to activate CCC ?
Brent Peluso Yes. The low amperage required to activate the LOR will not energize the CCC. It just sees the CCC as a wire. Hope this helps.
GFM
Interesting, what if you have 2 compressors in series... isn't that bad ? I was told loads in parallel, switches in series...
Brent Peluso In electricity, nothing is simple. What we may think of as always a no no, often works quite well in the right conditions. The lockout circuit is one of those. The more you learn about electricity, the more interesting it is.
GFM
Ok thanks GSM
Why doesn't the LOR switch open when power goes through it via the other switches?
The electricity will travel thru the circuit that has the lowest resistance. The high resistance of the coil of the LOR relay precludes enough power traveling thru it to energize the coil. I know this is hard to understand, and I will try to do another video attempting to explain why the electricity does this.
GFM
grayfurnaceman Thanx. I like your videos. Keep it up.
good vid...
Don't use lockout on a WR 5400 thermostat if u have a packaged A/C & heat pump WATHER IT'S a GAS PACK or NOT cause it can make it not run right believe me I've had many problems a packaged unit from the year 2000 or older have built in lockout delay. For units 2001 and later do use the lockout feature on this thermostat they have an electronic lockout delay witch need this.
Sounds like good info to know.
We have them in our trailer. They are wooden
hello I have a doubt what kind of relay I should use in LOR, when I have a 24v transformer.
The relay should have a 24 volt coil, and be much smaller than the relay for the equipment.
GFM
Great video