Bryan is back with basics of Common, Start and Run as it relates to Single Phase PSC motors. Read all the tech tips, take the quizzes and find our handy calculators at www.hvacrschool.com
Almost 15 years now doing this stuff everyday and i cant stop watching these videos. Amazingly accurate and necessary information for basic and in depth problem solving.
Bryan, Thank you, your video instruction is very clear and informative. You are an excellent instructor given you don't assume any prior knowledge on the part of the viewer. Also - you stick to business - no fluff (i.e. like listening to yourself talk), no annoying music etc. Excellent instruction all the way! I subscribed and look forward to learning from your other videos. Thanks so much! ps thanks for the outstanding illustrations - very helpful for visual learners.
Nice video. I knew all of this, but it took me a lot of brain racking to figure it out on my own. This is one of those things that some guys work around for years and years and never understand it. Awesome crash course for clarification/learning and very applicable.
3temanels highet midum comon factor startung . High and lowest common facter Runing .midum and lowest comon facter comon .comon ok gues s.starting R.Runing systiom ruing s. Starting s only statungok
Question for you, in the UK our compressor wires go straight to the printed circuit. I am new to the industry i want to learn and do well. As testing goes do I just wires from my board to compressor like you would do if you had capacitor?
my cpf sir is 8 layers sir but the problem is 5 6 7 layers cannot cooke the fish.how to adjust the txv.if i cant adjust.in what direction.thank you sir
What would happen if capacitor C is connected to same leg as compressor C. Less torque at start right because it still comes with phase shift from capacitor. Thanks for sharing
Common is the path back to power source. So if you hook that up to C, with R hooked to T1 and S to Herm... nothing would happen. You dont have a circuit. If you introduce T2 to the capacitor then you'd have a circuit, possibly (Herm and Fan aren't connected so if you put it on the opposite, no circuit. Put on C then you have a path to and from source.) The problem is you'd be phase shifting both windings, it might run backwards, it may not have the correct torque to start at all if they're both shifting the same. Im not sure without testing, I have a sacrificial motor here... needless to say it would NOT be operating correctly and probably shorten the life of windings or hopefully capacitor first.
Quick question I can't get a straight answer from anyone on this topic. Your thoughts would be greatly appreciated. Why when measuring voltage at a running compressor is there higher voltage than the input voltage?
I really enjoyed this video. Question. I have a tempstar 3 ton 1 phase home A/C unit. Looking at the compressor wire set up, it shows R - Red wire, C - Black wire, S - Blue wire. The blue goes to the start or HERM of the dual capacitor. The black is common wire, and red wire is the run. If I want to test the total inrush, which wire should I clamp my meter onto? Also, do u know where I can find the wiring diagram? Mine washed out. Model # TCA236AKC4, S# E052050914. Thanks. I hope u can help. John.
This video for clicked with me to create what I suppose is the "story", which is how I remember things. I'm terrible with remembering random things not tied to their reason. So the story goes like this: The run and start/aux windings on a motor must be connected to the same leg of power as they must be in phase with each other. The start/aux winding is then shifted in phase compared to the run winding by connecting the start and/or run capacitor in series with the start/aux winding to create a residual force between the windings' magnetic fields that gets the motor turning, and for the run capacitor after start up to also "tune" the motor for the most efficiency at the design load. Common (C) on any component is almost always localized to that component and has no relation to (C) on any other component. For instance, power from the same leg as the run winding is pigtailed to the (C) terminal on a dual capacitor where it is forked to both the compressor motor via (HERM) and the fan motor via (FAN) terminals. Whereas the (C) terminal on a motor is where the run and start/aux windings are tied (commoned) together to connect to the opposite leg of power to create a complete circuit with the line power. Going back to the first "rule", when using a dual capacitor both motors (compressor and fan) run windings are connected to the same leg of power since their start/aux windings are also connected to that leg of power via the dual capacitor (C) terminal.
Don't complicate it. You're completing a circuit, simple as that. The start windings are shifted out of phase with the main windings due to being run through a capacitor, this gives you the torque to get the motor running and in the correct direction. After that point they just provide extra emf at a different angle as the squirrel cage rotates but the main windings provide the real torque when they are pulsating. If you hook common wire of motor to C on capacitor and then the start winding on Herm (or fan if talking fan motor) then nothing would happen with Run going to contactor as there is no circuit. If you hook L2 up to the capacitor then you'd have a circuit but it might act funky because it has to loop power both main winding and start winding common through the capacitor to get back and forth from L2. Im guessing heating issues and possible rotational issues and capacitor issues if it ran at all. Needless to say, motor run goes to T1 as does C on capacitor and motor common to T2 assuming the hookup of the contactor correctly. Start goes to Herm. (Or fan if condenser fan) pretty easy.
So there is three pins right. You would connect the red phase to the common. Then the yellow phase to the start and the blue phase to the run pin. Then switch on
Regarding resistance values in 'Condenser FAN motors' resistance across the run winding will typically be higher than across the start winding. Check it out - its real
Only if you run the motor backwards... which it really shouldn't as the run windings are thicker gauge, which means lower resistance and less heat. The start winding typically don't fall out of the circuit on these motors. I just tested three. C TO R is lowest, C to S is middle, R to S is highest resistance just as it should be on any motor.
@@etherealrose2139 You would think so - and that is the way I used to teach it. If you do reverse S and R the motor will run backwards as you say but - I have a lab of about 16 different systems, all 2 ton, (lennox, york, etc) - few years back had my students identify the condenser fan motor C, S, R with the ohmmeter and wire things up only to find them all running backwards - after scolding each I found it was I who was mistaken. Each condenser fan motor had higher R winding resistance than S winding. My systems are all 2016 and newer so not sure if the ones you were checking are newer or older. I would be interested in what model you are testing - I could give you some of what I am testing. Best
Just a little confusing if you look at schematic/ drawing around 1:05 and then drawing at 4:15. You have L1 going to motor run at 1:05 then at 4:15 you have L1 going to motor common. Possible confusion if the new tech doesn’t completely understand 220 single phase as the common side of the capacitor an be loaded from either side of the motor starter/relay contactor as well common and run Otherwise, as always, a very nice video
Melvin292 - as with most contractors, there is line voltage in so, yes. T1, T2 is the opposing side of the relay. I’m sure just simplified for demonstration purposes here in this video
Sir please make a video on the basis of Outdoor Heat pump AQUANEXA any model of ANX-09, ANX-15, ANX-35, ANX-50, ANX-75 , please sir working of it and how it delivers hot water from ambient temperature along with Heat exchanger , Compressor, 4way valve , fan , condenser fins and it's PCB connect sequence of capacitor of single phase motor and conductor for 3phase motor, please 🙏 sir Using R410a refigerant
Bryan singal phàse motor fowerd reverse connection on both way starting winding get line supply with the running capacitor on this time current flow in (centrifugal switch off) both the coil one left to right other right to left is it not harmful to motor I am a Bigginer for the motor rewinding phàse Ripley me
Nice Demonstration 😎✌️
Y0#5507#
Comon n n rpowwr stating pojnt
L1 L2 runig startung c olp N sighal phas cr s .. starting winding runig winding c comon
Almost 15 years now doing this stuff everyday and i cant stop watching these videos. Amazingly accurate and necessary information for basic and in depth problem solving.
Can't wait for the 3 phase video
Simple clear concise explanation from a very knowledgeable teacher. Like the repetition!
Bryan, Thank you, your video instruction is very clear and informative. You are an excellent instructor given you don't assume any prior knowledge on the part of the viewer. Also - you stick to business - no fluff (i.e. like listening to yourself talk), no annoying music etc. Excellent instruction all the way! I subscribed and look forward to learning from your other videos. Thanks so much!
ps thanks for the outstanding illustrations - very helpful for visual learners.
Nice video. I knew all of this, but it took me a lot of brain racking to figure it out on my own. This is one of those things that some guys work around for years and years and never understand it. Awesome crash course for clarification/learning and very applicable.
3temanels highet midum comon factor startung . High and lowest common facter Runing .midum and lowest comon facter comon .comon ok gues s.starting R.Runing systiom ruing s. Starting s only statungok
Starting only cap cter is staring power dis contactung
The best hvac channel around !
Thank You for the Update.
Your Student from Nigeria
Thanks you, that's what it called, psc motor. Alot of CZcamsrs speak like fridges comes in one type of motor. I can tell you are well educated
Great explanation, very helpful, thank you very much.
My (most) favorite HVAC YTChannel.
I deeply appreciate this information it has opened my eyes
Great explanation and graphics.
Thanks for sharing.
Awesome Video ! Easy to understand. Thank you
Very informative..and easy to understand... thanks for the knowledge,god bless 🙏
Bryan, great video.. Thank you.
Great video Bryan👍👍
Thank you brother, great and educative video.
That was a quick review...Thanks
it was so helpful. i was trying to understand the wiring and i was so confused, but this video made it cristal clear. thanks a lot
Vrey vrey good shring tanyou gues
Great short video. I'm a mechanic but I find you field of work almost as interesting as mine.
Very good & clear explanations!! Any one can understand!! Great!!
Sorry, not anyone......
Excellent explanation 👍
Does the motor name plate give the normal current for the start and run windings or just one current value for both of them ? Thanks for nice video
Great tips.
Can you do a video to tell a difference in between a compressor on overload lock out and one with open windings.
great video as usual
Thank you very much. Very much helpful
Great explaining!!
How i can wire a compressor in a contactor without transformer 24 V?
Easily understood. thanks.
thanks. clear description.
Awesome video
I like this video because is short straight to the point
Nice demo
Great video
Good information. Ty 👍
Question for you, in the UK our compressor wires go straight to the printed circuit. I am new to the industry i want to learn and do well. As testing goes do I just wires from my board to compressor like you would do if you had capacitor?
Thanks again
Nice lecturing tnx bro
Thank you Sir.
sir how to adjust the txv in the cpf decrease superheat.increase superheat
Awesome. Thanks Sir. 😊
Vrey good
So the high resistance is coming from two terminals of capacitor which is herm and fan?
my cpf sir is 8 layers sir but the problem is 5 6 7 layers cannot cooke the fish.how to adjust the txv.if i cant adjust.in what direction.thank you sir
How do you reverse the direction of the fan motor in this situation?
What would happen if capacitor C is connected to same leg as compressor C. Less torque at start right because it still comes with phase shift from capacitor. Thanks for sharing
Common is the path back to power source. So if you hook that up to C, with R hooked to T1 and S to Herm... nothing would happen. You dont have a circuit. If you introduce T2 to the capacitor then you'd have a circuit, possibly (Herm and Fan aren't connected so if you put it on the opposite, no circuit. Put on C then you have a path to and from source.) The problem is you'd be phase shifting both windings, it might run backwards, it may not have the correct torque to start at all if they're both shifting the same. Im not sure without testing, I have a sacrificial motor here... needless to say it would NOT be operating correctly and probably shorten the life of windings or hopefully capacitor first.
Thanks a lot!!!
Estou no Brasil e acompanho seus vídeos , excelentes...
Thank you
thank you
U are the best 👌 👍
"C" on the cap goes to "Contactor" one HVAC person told me how to remember where the wires get connected to the CAP.
Start winding ,wile running , is an artificial phase that is that assists in the correct direction.
Good explantion
Hello there
Is there any way to add a reversing valve to spilt AC and make it heat as well?
A heat pump
How about connecting a bojack start/run into a circuit on a power flow lx pump motor.. any suggestions ? Thanks for you time!
can you do a video on ke2 ?
Informative
Quick question I can't get a straight answer from anyone on this topic. Your thoughts would be greatly appreciated. Why when measuring voltage at a running compressor is there higher voltage than the input voltage?
I really enjoyed this video. Question. I have a tempstar 3 ton 1 phase home A/C unit. Looking at the compressor wire set up, it shows R - Red wire, C - Black wire, S - Blue wire. The blue goes to the start or HERM of the dual capacitor. The black is common wire, and red wire is the run. If I want to test the total inrush, which wire should I clamp my meter onto? Also, do u know where I can find the wiring diagram? Mine washed out.
Model # TCA236AKC4,
S# E052050914. Thanks. I hope u can help. John.
How can we trace common run and start for inverter compressor...plzzzzzz give me idea
An inverter compressor does not have common,start,run. It is usually a small 3 phase motor.
This video for clicked with me to create what I suppose is the "story", which is how I remember things. I'm terrible with remembering random things not tied to their reason. So the story goes like this:
The run and start/aux windings on a motor must be connected to the same leg of power as they must be in phase with each other. The start/aux winding is then shifted in phase compared to the run winding by connecting the start and/or run capacitor in series with the start/aux winding to create a residual force between the windings' magnetic fields that gets the motor turning, and for the run capacitor after start up to also "tune" the motor for the most efficiency at the design load.
Common (C) on any component is almost always localized to that component and has no relation to (C) on any other component. For instance, power from the same leg as the run winding is pigtailed to the (C) terminal on a dual capacitor where it is forked to both the compressor motor via (HERM) and the fan motor via (FAN) terminals. Whereas the (C) terminal on a motor is where the run and start/aux windings are tied (commoned) together to connect to the opposite leg of power to create a complete circuit with the line power. Going back to the first "rule", when using a dual capacitor both motors (compressor and fan) run windings are connected to the same leg of power since their start/aux windings are also connected to that leg of power via the dual capacitor (C) terminal.
Don't complicate it. You're completing a circuit, simple as that. The start windings are shifted out of phase with the main windings due to being run through a capacitor, this gives you the torque to get the motor running and in the correct direction. After that point they just provide extra emf at a different angle as the squirrel cage rotates but the main windings provide the real torque when they are pulsating.
If you hook common wire of motor to C on capacitor and then the start winding on Herm (or fan if talking fan motor) then nothing would happen with Run going to contactor as there is no circuit. If you hook L2 up to the capacitor then you'd have a circuit but it might act funky because it has to loop power both main winding and start winding common through the capacitor to get back and forth from L2. Im guessing heating issues and possible rotational issues and capacitor issues if it ran at all. Needless to say, motor run goes to T1 as does C on capacitor and motor common to T2 assuming the hookup of the contactor correctly. Start goes to Herm. (Or fan if condenser fan) pretty easy.
I think this article is well written. Thanks
Thankyou vrey good sart s runing wing power sarting only start comon c..over old prtcating wininding
How to check a capacitor for that singl phase mptor?
Great
how about if 3phase compressor?
HI BRYANT IS LUIS VERAS YOU TRAINING ME BACK IN 2004 AT DEL-AIR
So there is three pins right.
You would connect the red phase to the common. Then the yellow phase to the start and the blue phase to the run pin. Then switch on
Regarding resistance values in 'Condenser FAN motors' resistance across the run winding will typically be higher than across the start winding. Check it out - its real
Only if you run the motor backwards... which it really shouldn't as the run windings are thicker gauge, which means lower resistance and less heat. The start winding typically don't fall out of the circuit on these motors. I just tested three. C TO R is lowest, C to S is middle, R to S is highest resistance just as it should be on any motor.
@@etherealrose2139 You would think so - and that is the way I used to teach it. If you do reverse S and R the motor will run backwards as you say but - I have a lab of about 16 different systems, all 2 ton, (lennox, york, etc) - few years back had my students identify the condenser fan motor C, S, R with the ohmmeter and wire things up only to find them all running backwards - after scolding each I found it was I who was mistaken. Each condenser fan motor had higher R winding resistance than S winding. My systems are all 2016 and newer so not sure if the ones you were checking are newer or older. I would be interested in what model you are testing - I could give you some of what I am testing.
Best
Just a little confusing if you look at schematic/ drawing around 1:05 and then drawing at 4:15.
You have L1 going to motor run at 1:05 then at 4:15 you have L1 going to motor common.
Possible confusion if the new tech doesn’t completely understand 220 single phase as the common side of the capacitor an be loaded from either side of the motor starter/relay contactor as well common and run
Otherwise, as always, a very nice video
Melvin292 - as with most contractors, there is line voltage in so, yes. T1, T2 is the opposing side of the relay. I’m sure just simplified for demonstration purposes here in this video
If the connection to the contactor were reversed it would be the same operation
At 2:10 what do you mean by "one side of power" and "another side" of power? Power has "sides"??
🙏👏
The run capacitor causes a 90° phase shift to start and run the motor.
Good
If this is single phase we need a neutral. Where is that connected?
220 single phase.
Why is it called run capacitor if it is in series with start winding
Pls clear this doubt
Start/Run capacitor is what they call them I believe when only one cap is used. If there are two CAPs, one is start and the second one is run.
What about the common. Is that the Hot or the neutral?
I would say hot, if not it would be 120V
I have only 2legs on my compressor
Fridge compressor very hot
Sir please make a video on the basis of Outdoor Heat pump AQUANEXA any model of ANX-09, ANX-15, ANX-35, ANX-50, ANX-75 , please sir working of it and how it delivers hot water from ambient temperature along with Heat exchanger , Compressor, 4way valve , fan , condenser fins and it's PCB connect sequence of capacitor of single phase motor and conductor for 3phase motor, please 🙏 sir
Using R410a refigerant
4:55
Bryan singal phàse motor fowerd reverse connection on both way starting winding get line supply with the running capacitor on this time current flow in (centrifugal switch off) both the coil one left to right other right to left is it not harmful to motor I am a
Bigginer for the motor rewinding phàse Ripley me
No one talks about the 90 degree phase shift the start capacitor provides...
You can have a compressor with no run capacitor
The title is wrong because I don’t know the analogy at first place, let alone how do they work.
Having some struggles, to understand.
Not too long ago I would have understood 15% of what you said......
Why does Brian work domestic he should be doing heavy commercial $$
Start winding resistance is high, eventhough starting current is also high, Why? even resistance is high should be current low......dont understand
The HERM does what?
Hermetic compressor.
Herm on cap goes to start on compressor which is labeled S but might be hard to see.
It can be easier to understand in illustration than saying.
Why is it called common if it's connected to power?
Hard head we need to see actually connection of the machine to understand
Sorry, major ignoramus here. on the diagram at 1:40, what is L1 and L2, and what is that OL cap with a line thru it?
U forgot how to define common run n start
Awesome