Thanks Zack. I had hard time interlocking Washroom fan and furnace in the basement. Please could you provide me and wiring diagram for that. The problem is common for legal basement. Thank you
very nice info., on a 1000 hp 2300vac motor is there a formula on setting the timing resistance 5-steps on the 3 phase resistors grid to the bypass grid in run mode? 🤔thanks🙂
thanks for the video. if you were to replace a drum sw that controls the wrm with a pendant control operating a vfd to supply power to stator what would be the best setting of the resistors for the rotor? high,med or low redistance?
Inductive reactance in the rotor is high when first started (due to the high slip speed) which is exactly why we want high resistance also for good starting torque. Resistance in a SCIM can't be changed to match inductance which is the entire advantage of a wound-rotor.
I recently discovered a very old single phase 115/230 1/2 horse WRIM in an attic. The weird bit here is that it uses a commutator like a dc motor instead of single pole slip rings, and there is no provision for external resistors. The brushes simply connect some points on the commutator to other points on the commutator. The motor is reversed by rotating the brush assembly relative to the housing. So given that there is no resistor aided start going on here, why does this motor exist? What is the advantage of this over a regular squirrel cage motor? Edit: Looks like this is a repulsion motor. They did this to achieve high starting torque before the use of start capacitors was practical.
The waste water treatment facilities throughout my city use WRIM’s for the main influent sewage pumps. More reliable than VFD’s for that purpose because of the severe and corrosive environment. They experimented with a VFD motor and it wouldn’t stop crapping out (no pun intended) so the WRIM’s proved to be worth the extra maintenance. I have a question if you don’t mind. If I connect 3-single phase transformers for 3-phase (parallel) operation, do I simply divide the load by 3 to get the KVA rating of each transformer? Of course the transformers should only be loaded to 80%, I’m assuming.
@@ZackHartle Understood, parallel was the wrong choice words.Thanks for your reply. Your parallel RLC video got me hooked on the voltage and current triangles. They dont allow us to use socahtoa functions on the calculator for the NYC City Electricians exam, but because of that video I’m able to do those parallel RLC’s with the combination (Z) coils now. First time I took that test back in 2006, they hit me with a 3 part question based on a parallel RLC circuit just about the same as the one in your highly viewed video. They didn’t even show us a parallel RLC in the prep course, let alone one with an RL coil. When I first saw that video of yours it was a big “Aha!” moment. I called all my electrician friends and told them to check out that video just to prove I wasn’t lying about that test question. Still got an 86.25 on it but if I had your help back then, I’m sure I could of hit a higher mark.
Great video. 100 times more comprehensive than my teachers. Thank you. You've earned a well-deserved subscriber here.
The way I write on through the glass is really impressive and the lecture is very informative .thanks a lot buddy
The best basic explanation of a wound rotor motor I have seen so far, thanks Zack!
That's great to hear. Thanks for watching!
This is amazing, much easier to learn from these videos than actual classes.
Glad you think so!
Thank you Zack! Very helpful indeed. Have a great day as well!
Happy to help!
@@ZackHartle Thanks in part to you I aced my test on motors! Appreciated.
@@stephencarmichael667 Glad to hear it!
thank you Mr. Zack
Thanks Zack. I had hard time interlocking Washroom fan and furnace in the basement. Please could you provide me and wiring diagram for that. The problem is common for legal basement. Thank you
There's so many different options depending on the exact situation. I would recommend finding an electrician in your area to come take a look.
very nice info., on a 1000 hp 2300vac motor is there a formula on setting the timing resistance 5-steps on the 3 phase resistors grid to the bypass grid in run mode? 🤔thanks🙂
thanks for the video. if you were to replace a drum sw that controls the wrm with a pendant control operating a vfd to supply power to stator what would be the best setting of the resistors for the rotor? high,med or low redistance?
Inductive reactance in the rotor is high when first started (due to the high slip speed) which is exactly why we want high resistance also for good starting torque. Resistance in a SCIM can't be changed to match inductance which is the entire advantage of a wound-rotor.
Great stuff Zack! Is it possible to fit a wound rotor in place of a squirrel cage rotor in an induction motor? Thanks for a quick answer.
In theory it would work, if it fit perfectly. Just may not be quite as efficient.
I recently discovered a very old single phase 115/230 1/2 horse WRIM in an attic. The weird bit here is that it uses a commutator like a dc motor instead of single pole slip rings, and there is no provision for external resistors. The brushes simply connect some points on the commutator to other points on the commutator. The motor is reversed by rotating the brush assembly relative to the housing.
So given that there is no resistor aided start going on here, why does this motor exist? What is the advantage of this over a regular squirrel cage motor?
Edit: Looks like this is a repulsion motor. They did this to achieve high starting torque before the use of start capacitors was practical.
Do you write backwards? Thanks for the in-depth video.
Nope, it's just fancy camera tricks
Look at the wedding ring on the right hand. He cant trick me!!!!!!!
The waste water treatment facilities throughout my city use WRIM’s for the main influent sewage pumps. More reliable than VFD’s for that purpose because of the severe and corrosive environment. They experimented with a VFD motor and it wouldn’t stop crapping out (no pun intended) so the WRIM’s proved to be worth the extra maintenance. I have a question if you don’t mind. If I connect 3-single phase transformers for 3-phase (parallel) operation, do I simply divide the load by 3 to get the KVA rating of each transformer? Of course the transformers should only be loaded to 80%, I’m assuming.
Very cool about the use of WRIMs still.
Yep basically, although you wouldn't connect them directly in parallel
@@ZackHartle Understood, parallel was the wrong choice words.Thanks for your reply. Your parallel RLC video got me hooked on the voltage and current triangles. They dont allow us to use socahtoa functions on the calculator for the NYC City Electricians exam, but because of that video I’m able to do those parallel RLC’s with the combination (Z) coils now. First time I took that test back in 2006, they hit me with a 3 part question based on a parallel RLC circuit just about the same as the one in your highly viewed video. They didn’t even show us a parallel RLC in the prep course, let alone one with an RL coil. When I first saw that video of yours it was a big “Aha!” moment. I called all my electrician friends and told them to check out that video just to prove I wasn’t lying about that test question. Still got an 86.25 on it but if I had your help back then, I’m sure I could of hit a higher mark.
Thank you mr. Zack ❤
My pleasure!
Very beautifully explain
Thank you so much 🙂
thanks for your video.
Great work 👏🏾
Thank you 🙌
Good video. Thanks
Pls make video on elevator motor control
Maybe one day.
You can check out these videos though that might help you out: ua-cam.com/play/PLQS5IUr7LE395MM2Bw6EDAFKWeK3eXtEY.html
Good work.appreciated
Thanks a lot
nice
awesome
I like it❤
Maintenance requirements is not a disadvantage 😅😅😅 Job security 🙏🏿
I'm distracted by the idea that he's writing backwards for our convenience
Theres no real good video going in depth about, cage vs wound motors, might be a good video idea ;)
Great idea. I'll add it to the list