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Electric Garage-Door Motor Won't Run Under Load

12/28/2016 2:17 AM

Hey guys, zero engineering know how and did a bit of poking around the forums via searching but didn't find much. My grandfather's garage door motor suddenly stopped working a couple nights ago (along with the heater, merry xmas). It's a 20 year old system he refuses to replace, motor label posted as attatchment here. When he took the cover off and disconnected the shaft drive from the pulley the motor seemed to operate. After reconnecting to the load, nothing. I called Westinghouse for support and they just laughed at me saying to replace it with something newer. I know the motor is old, but I really can't imagine it having gone completely. Any ideas? Please tell me what other information I can provide about the situation and sorry for the noobie question.

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#1

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 2:30 AM

As the motor runs, quite possibly it is fine and the mechanism is jammed somewhere else?

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#5
In reply to #1

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 6:42 AM

Many garage door mechanisms, including two known here, reverse on torque settings if an obstruction such as a bonnet/hood is reached before reaching the closed position. A jammed mechanism and an obstruction under the door on travelling closed would have the same effect on the motor's controls should such a facility be present.

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#2

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 4:17 AM

Check limit switches.

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#31
In reply to #2

Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 8:38 AM

Let me double that suggestion.

I did maintenance for 8 years on the side until my electrical control work became full time. We have many "garage door" type controls on automated linear polishing machines here, and every time one went down, it was the limit switches that were at fault.

Motors last a lot longer than mechanical limit switches.

One other possibility that was not mentioned - does the door have a light sensor across the back side of the door to sense a body in the line of travel? Might check the sensor for dirt on the lens.

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#56
In reply to #2

Re: Electric Garage-Door Motor Wont Run Under Load

12/30/2016 3:00 AM

But he says the motor runs, when de-coupled from the load. If it were limit switches/sensor, surely it still wouldn't run.

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#66
In reply to #2

Re: Electric Garage-Door Motor Wont Run Under Load

05/13/2020 4:03 PM

Have you checked the start cap on motor?

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#3

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 5:10 AM

Going over in the morning and will check for any obvious obstructions and see if I can easily turn the mechanism.

I tried doing a Google search for limit switches, but am not sure how to check them?

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#4
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Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 6:39 AM

When the motor hits either end-of-travel or maximum torque, it should switch off. Limit switches will carry out the former, particularly when the mechanism hits the fully-open mark.

It is likely, and not known for certain from here, that the fully-closed position is determined by torque, as determined by setting a maximum trip point on the motor current when the travel is beyond a certain point.

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#6

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 7:55 AM

Add to the list to check your door spring, is it broken. It counterbalances the weight of the door.

Also check the hinges on the door panels, at times this crack and get out of alignment.

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#7

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 8:59 AM

Remove the drive form the opener and cycle the door by hand up and down taking note where any resistance is met.

Also.. with the unit connected properly. push the button to raise/lower while manually assisting in the raise/lower function of the garage door opener. (provide some push/pull force to help it limp past obstruction)

look out for a section of rail/ rollers /door that buckles or moves unnaturally during these operations.

Something is loose or tight

..don't get Westinghoused.

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#52
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 6:19 PM

I have to disagree, if you push / pull to limp it past an obstruction, it may be such that doing so may cause the mechanism, roller, guide etc to jamb. And it might not want to go back the other way so easily.

I would get a helper. One lifts the door, the other watches the door and looks for anything out of place.

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#8

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 9:35 AM

One way to rule the motor out as the problem would be to put a load on it separate from the door opener. Just be careful, if it is a gear motor it could be high torque and cause damage with whatever you load it with. a first thought would be to put a pulley on it and try to lift a weight but if it is fast, it might be difficult, if it is slow, it might be difficult to load it without overloading the structure it is attached to.

Best advice, come up with a plan, analyze what could go wrong then account for the risks.

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#9

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 10:14 AM

The springs that come with the garage door rail system actually do most of the lifting. If a spring is broken, the garage door motor usually does not have enough hp to lift the door by itself.

Check the springs to see if one is broken. If it's a torsion-style spring system, you can have a broken torsion spring and not even notice it's broken. If that's the style, and one of the springs is broken, you might look for a tiny gap or crack in the spring.

This happened to me once. I had a garage door with a torsion spring system lift mechanism. One of the springs broke, and the garage door motor was not able to lift the door. It took me a couple days to realize what the problem was. I had to have a pro remove the broken spring and install a new one - then the garage door opener was able to work normally again.

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#11
In reply to #9

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 10:34 AM

Yes, I replaced mine about 2-3 years ago. Its easy enough to replace if you have the basic tools. May have to get a 4' length of 1/2" pipe and cut it in half. But you have to understand, that by winding up that spring, there I a lot of stored energy in it, and one has to be careful.

And if you spring did go. Pull on the emergency cable (you use when the power goes out) This will detach it from the garage door opener chain. If you can't lift it, more then likely on of your springs is broke. You may have (2) springs, one is a left hand wound, the other is a right-hand wounds. The springs windings are designated by colors red and black. At least on mine brand, I think it was a Dayton or Dalton???...

After which I actually did an overall inspection of the door and track itself. I noticed that 1/2 the hinges were cracked or broken completely..

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#14
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Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 12:21 PM

Exactly. There is a LOT of stored energy in the springs, which is why I hired a pro.

My garage door was an old, wood, 2-car garage door. Before the repair guy got there I needed it opened, and I felt like I was about to have a heart attack or aneurysm lifting that thing.

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#15
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Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 12:36 PM

There is a LOT of stored energy in the springs, which is why I hired a pro.

Its actually quite easy... But I have to admit, I was concerned when I was cranking it up... but it helps when you installed one before.

I can't recall if I bought both the Left-hand and the right-hand springs... Normally I do.

Our house isn't that old, but we weren't the original owners. The original owners had it for about 2-3 years, but I think they put in their own garage door opener... because the control itself by the motor had wires hanging out of it, and had problems opening about 10% of the time.

I got tire of it, and tore it apart organized it made sure the connections were tight, before I would look at a new one.

Before the repair guy got there I needed it opened, and I felt like I was about to have a heart attack or aneurysm lifting that thing.

When the spring broke, my girlfriend called and said the garage door wouldn't open she thought it was something wrong with the motor.

I told her to pull the cord with the orange ball on, like the picture SE posted. She called back and said it was stuck, ( thought to myself,... stupid girl, you'd starve to death if I wasn't around) I only thought that,... I didn't say it... fortunately, we had a truck outside for her to go to work.

When I got home, I tried it, that door is heavy. Saw what the problem was, and I order a spring that night, Got it 2 days later and installed it. But it concern me, because the light sheet metal was deforming a bit as I torqued it.

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#51
In reply to #11

Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 6:09 PM

On some garage doors, when you pull the emergency release cable, the drive system is mechanically disconnected from the the lift mechanism and from the load.

Try operating it now.

You can observe it's operation and see if there is abnormal noise or gear grinding.

Splitting the system into two subassemblies can help you determine where the problem may be.

Others have commented here on lots of good ideas, let us know how it goes.

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#53
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 6:29 PM

I had a neighbor whose garage door spring ( like Phoenix 911 describes ) break.

When the repair man showed up he suggested that both springs be replaced, he said the other spring had a 50/50 chance of breaking soon too.

2 months later, he was back making another service call to replace the other spring.

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#62
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Re: Electric Garage-Door Motor Won't Run Under Load

01/03/2017 11:41 AM

Most likely, since it went out "all at once" and a broken spring matches that fact perfectly.

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#10

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 10:23 AM

Are you sure there is no commonality between the heater going out and the garage door opener not functioning? Could there be a mains problem? What part of the heater went out, was it the fan motor? Hmm...

Do check out the door mechanism, springs, rollers, alignment, etc.

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#17
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Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 1:43 PM

The issue of the heater going out at the same time has me wondering too. I'm thinking he may have lost a neutral connection somewhere. There might be another indirect path to ground that is being taken so things like lights seem to work fine, but under any appreciable load, it presents too much resistance and the voltage drops, rendering the more obvious "heavy" loads like the opener and the heater seemingly inoperable. The scary thing is that this if this is the case, the refrigerator compressor is likely affected as well and can result in a VERY expensive repair!

Eliminate the obvious things like the broken springs, but if not something like that, call a good electrician, IMMEDIATELY.

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#28
In reply to #10

Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 1:37 AM

Good thoughts. Maybe there is a high resistance connection somewhere, that is preventing full voltage/current to both units...

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#54
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 6:47 PM

On a lot of garage doors, the power is supplied via a standard 3 prong cable, plugged into an adjacent J-box. Plug anything into the duplex on that J-box, if it works, then you have a working neutral.

I didn't notice a mention of operating voltage ( I can't read the voltage on the motor name plate decal,). A typical home garage door motor uses 120 V, a home heating ( gas, propane ) unit - 80/90% will feed 120v to the control module, a 70% may use a 120v /24v step down transformer and an a c compressor usually is 240v and up.

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#39
In reply to #10

Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 2:08 PM

I was reading through the replies hoping someone would mention the heater.

It was one of the problems originally stated and it should not be ignored.

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#41
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 2:29 PM

I thought I did, and then someone else did also. It really does sounds like bad wiring, squirrels in the attic, etc., loose neutral. This job requires a perfesshunal (LOL).

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#42
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 2:49 PM

What do we know about it to allow us to consider it? Is it electric? Is it also on a 120VAC circuit? Is it on the same circuit? Is it totally non-related and just a coincidence? I know nothing, nothing.

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#44
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 3:59 PM

I know I did.....having them both stop working at the same time, is a strong indicator....

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#12

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 11:13 AM

There could be any number of problems here, I have done some work on these and can point out the most common problems....The springs over time weaken, this leads to more strain on the motor which leads to more strain on the capacitor...the first thing to do is disconnect the door from the mechanism, you should have a cord or chain hanging that unhooks the door from the drive chain with a yank....once the door is disconnected lift it up to see if the springs are properly working, it should have force lifting it half way and you should need to push the second half, albeit with not much force...If the door is a heavy lift from the closed position you will need to adjust or replace the springs, this needs to be done by a professional, the springs are very dangerous....Now with the door disconnected try the up/down switch again....If the door opener cycles through it's range up and down, then the springs were the problem....If it doesn't you need to troubleshoot the motor....

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#13
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Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 11:44 AM
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#67
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Re: Electric Garage-Door Motor Wont Run Under Load

05/13/2020 8:28 PM

To troubleshoot the motor you need a multimeter and an amp probe...check the voltage going to the motor, and check the amperage draw when going up and the voltage coming in..

.If you are getting excess amperage draw above the motor rating ~4 amps, then check the run capacitor for the motor...

if you don't have a capacitor tester, then use the continuity setting on the multitester, set on 200 ohms, disconnect the wires on the capacitor, taking note of locations, best to take a picture, then touch the probes to the 2 capacitor wire connections simultaneously, you should get a quick movement of the needle to pegged position then back to starting position, if this is not the case, either the needle doesn't move, or it pegs and stops there you have an open capacitor or shorted capacitor...replace it...

If the capacitor is good and the motor is over drawing amps, you have a weak motor, and needs replacement, or the electric supply is weak...If the motor is not drawing over amps but is still shutting off, then the limit switch is malfunctioning...

If the voltage is dropping when the motor runs you have a bad connection, possibly a bad circuit breaker or burnt wire...These are just some things that can go wrong with the motor...

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#16

Re: Electric Garage-Door Motor Wont Run Under Load

12/28/2016 12:40 PM

After all the excellent suggestions here, I'm a bit reticent to make an obvious one: WD40 followed by a thicker oil (the rest of the mechanism not the motor itself).

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#55
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Re: Electric Garage-Door Motor Wont Run Under Load

12/29/2016 6:57 PM

Usually the drive is lubricated with a grease. WD 40 may wash out or contaminate the grease requiring a somewhat lengthy and messey re-lube job. It will be a real bear if you got to disassemble it to do an A1 job.

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#18

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 5:53 PM

Just tried some of these suggestions. Nothing yet. It seems the motor is not working under resistance as it lowers the garage door fine. If door is unattached, it works normally but if any load is put on it simply hums as if the motor is experiencing too much resistance to fully turn the shaft.

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#19
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Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 6:23 PM

So, the door goes down just fine.

How did the door get 'up'?

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#29
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Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 1:41 AM

Does the heater have a problem still? If yes, repair that first.....you never know!!

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#33
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Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 9:02 AM

We needed to know about the humming.

A capacitor or starting switch provides starting torque to get the equipment moving.

Look for a cylinder about 4" long, 1-1/4" diameter, with two wires attached at one end, the wires connect to the same place the motor is wired to, you'll have 3 wires and a ground. It can be mounted on the motor under a metal cover, but I think garage door openers mount them separately. With both wires off the capacitor, test it with your ohmmeter, it should dip to zero then rise, reverse the ohmmeter polarity, and you should see the same.

Google 'garage door opener motor capacitor' to see what they look like.

A stuck centrifugal switch means you might have to open up the motor, not a really tough job, but easier to work on out of the opener.

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#35
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Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 11:19 AM

Thats the test I still use occasionally, always good to know about! But that test may not tell the whole story.....

I had a single phase induction motor problem, about 25 years ago on a large industry printer and it passed that test, but when I got it checked out on a proper cap meter, it had lost more than half its capacity.

Got a replacement of the right value and the motor ran properly again....I had to fly to Sweden to find that one out! The locals had only done the simple check....

Since then, I have made a capacitance meter (add on for digital meter, but the range was a bit too small for large electrolytics!) and finally bought a meter specifically for caps & inductances!! It was not expensive and appears to be very accurate....or should I say, more than accurate enough!!

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#20

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 6:28 PM

Helped up by hand, all the way. Tried letting the motor handle various points of lifting but it would stop under any load. The door is not super hard to lift, just seems the motor keeps stopping under load and humming.

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#21

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 6:37 PM

Also, when the motor is let to run freely, unattached from the door, I can stop the pulley with my hand easily at any stage (even after it has fully spun up). Shouldn't this take some effort on a motor running at 1/3 hp?

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#22

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 9:09 PM

Check the motor run capacitor. It's ratings are on the nameplate

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#23
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Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 9:12 PM

50 Mfd/250 volts

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#30
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Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 1:42 AM

A very good point....

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#24

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 10:51 PM

After reading everything suggested, it sounds almost like either a counter balance spring bracket cracked or one of the set screws in the counter balance system came loose or as mentioned before, a broken spring, thus allowing the counter balance spring to unwind. Dealt with that a couple different times.

I use 3/8" or 1/2" rebar about 12- 18" long for cocking (preloading) the counter balance spring if it's a horizontal spring, if it's two vertical springs on each side, choice words are in store!

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#26
In reply to #24

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 11:30 PM

The springs seem fine, we oiled them up but there is no major difficulty in lifting the door. What's concerning is the ease with which I can stop the motor just by grabbing or putting my hand over the belt pulley after the motor has gotten to full speed. It feels like far less than 1/3hp of force

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#32
In reply to #24

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 8:46 AM

or one of the set screws in the counter balance system came loose

That's correct, I like to add, that the shaft the set screws lag into is not a shaft, but a light gage tube that's easily deformed.

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#25

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 11:30 PM

What you have to do is start at the beginning.
There will be 4 wires to the motor.
For low RPM they will be in parallel.
This will give you 2 wires.
Connecting them to the mains will allow the motor to rotate clockwise.
Separate the wires and connect one pair around the other way. This will make the motor reverse.

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#27

Re: Electric Garage-Door Motor Won't Run Under Load

12/28/2016 11:33 PM

Could this be a weak capacitor issue? I'm going to look for a locally available one in the morning.

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#34
In reply to #27

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 9:34 AM

Redman-

Very likely you have a faulty starting/running capacitor since motor torque is low...

After 20 years, the electrolyte must have dried up! Typically it is two AC caps in one package, with 3 terminals... Try to get one rated at least 35 - 70 mfd, with 300 V operating voltage!

good luck.

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#36
In reply to #34

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 11:50 AM

You wrote:-

Try to get one rated at least 35 - 70 mfd, with 300 V operating voltage!

As far as I am aware, the value of capacitance needs to be correct, or close to, the original caps marking, as the inductance of the motor plays a heavy role in the way the circuit operates. That was how it was explained to me, more years ago than I care to remember.....

So the wrong value could easily produce a similar problem as before, or eventually damage the motor windings by overheating them, which could take a long time, eg. not immediately obvious that the cap is the wrong value and causing the problems.

Furthermore, voltage rating has a lot to do with the local mains supply and you did not specify that.

I personally use for European systems at 220-240VAC (which peaks at around 312 volts if I remember correctly), always try to get anything voltage sensitive (caps and semiconductors) built for 800 volts or better, as "spikes" can cause damage to underrated components....back emfs from motors at power on/off times, which happened to be taken at the top or bottom of the mains cycle....for example.

So you get say a 300 volt spike on a 312 volt mains peak....for example....over 600 volts!

Therefore there is no "one" start capacitor for any voltage and any motor....it must be correct.

Also, there are caps rated just for starting, that are taken out of circuit by the motor contact, and there are caps for motors where the cap is in circuit all the time, adding extra torque.

The higher quality cap for continuous running has a far higher price. This can usually also be ascertained by reading the label on the cap.

If the label is unreadable, the first link below has a simple formula for calculating the capacitance value required, and then its best to by the better quality "running" cap, just to be safe......or taking the time to identify the motor type accurately before purchase of a cap.

See here:-

Single-phase-capacitor-sizing 1

motor_run_capacitors_sizing

I hope that clears up any misunderstandings.....

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#37
In reply to #36

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 12:49 PM

I agree that as much as possible the OP should seek the same ratings as found or as indicated with the unit in question...

While I believe my comment started with the word "typically", which in my opinion cover any uncertainties!

Uncertainties associated with the OP's garage door opener location, its components, make, model, etc?

Also, I'm pretty sure you are aware that electrolytic capacitive tolerances can go as much as +/- 20% of rated value...

My search examples give you some typical values...

http://ep.yimg.com/ay/yhst-16416632405890/liftmaster-30b363-garage-door-opener-capacitor-3.gif

https://www.google.com/search?q=garage+door+opener+capacitors&rlz=1C9BKJA_enUS724US724&oq=garage+door+opener+capacitors&aqs=chrome..69i57j0l3.21477j0j7&hl=en-US&sourceid=chrome-mobile&ie=UTF-8

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#38
In reply to #37

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 1:49 PM

For what it is worth, this opener was stated to be very old, maybe the operator drive and worm gears are worn out and snagging up or misaligned now and dragging.

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#40
In reply to #38

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 2:09 PM

True!

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#43
In reply to #37

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 3:58 PM

I agree they are variable, but owning a cap meter, precludes that being a problem for me personally.....

But as the links I posted mentioned, you can burn out the motor by not being relatively (within 20% as you mentioned) of the correct value....and a wild guess could be miles off!!

For good working, "typically" is still only a guess, and may cause someone here to do some serious damage to equipment...

Lets just agree, thats your method and not mine!!

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#45

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 5:01 PM

Stuck centrifugal switch shouldn't hinder torque in this manner. My grandfather is an electrician. Heater going out was coincidental and they are not related problems.

"high resistance connection somewhere, that is preventing full voltage/current to both units..."

how would I look for something like this?

its not that the motor isn't spinning up, it's just super weak.

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#47
In reply to #45

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 5:28 PM

Measure the motor voltage at the terminals, while connected to the mechanical load. Should not be a whole lot lower than the same reading when running the motor disconnected from the track. (two person job)

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#48
In reply to #45

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 5:40 PM

" My grandfather is an electrician." Then why isn't he out there giving you guidance? He should know how to troubleshoot the problem, electrically anyhow.

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#50
In reply to #45

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 5:49 PM

I suppose it's possible that residual magnetism might allow a centrifugal switch motor come up to speed only on the run winding (Switch stuck open). If so, I'd think you could stop the motor shaft from turning by hand, from a stop, but not once it is up to speed.

Can't find a capacitor?

The thermal switch could be the source of low motor voltage, you could try measuring the resistance of the two motor windings with your ohmmeter, they should be pretty low, look like a short circuit, 1 to 1.5 ohms. If the thermal switch is bad, it could read much higher, or even open with a standard ohmmeter.

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#46

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 5:07 PM

I explained how to start the testing. I have fixed 35,000 electrical and electronic devices and you haven't even responded to my entry.
You need to know if the output is weak in both directions.

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#49
In reply to #46

Re: Electric Garage-Door Motor Won't Run Under Load

12/29/2016 5:49 PM

A possible explanation, assuming a cap/run motor, is still the cap!!

regards

Andy

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#57

Re: Electric Garage-Door Motor Won't Run Under Load

12/30/2016 8:11 AM

Merk mentioned the heater that quit in a post and I returned with a reply indicating we have no data on this what so ever. So - is the heater just a side note, or is this something we need to consider as well? Are we chasing a motor failure when we need to be looking at a much larger problem?

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#58

Re: Electric Garage-Door Motor Won't Run Under Load

12/30/2016 12:43 PM

If the capacitor is the problem, W.W. Grainger carries motor-start capacitors. Is there one near you?

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#59

Re: Electric Garage-Door Motor Won't Run Under Load

01/01/2017 4:46 PM

A certain Brit left this in my mem banks.

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#61
In reply to #59

Re: Electric Garage-Door Motor Won't Run Under Load

01/01/2017 7:01 PM

That's my kinda garage door opener!

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#60

Re: Electric Garage-Door Motor Won't Run Under Load

01/01/2017 5:04 PM

If the motor is weak in both directions, the cap will be at fault.
But you have to do the test I specified above to determine this.

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#63

Re: Electric Garage-Door Motor Won't Run Under Load

01/03/2017 6:47 PM

Does the door have torsion springs? It may be one of the springs is broken. Disconnect the door from the door opener and try to cycle the opener. If it moves the latch assembly without the door attached, then it might be a broken torsion spring. The springs on my garage door break every 5-6 years, and I spray them with WD-40. To have someone replace both springs will cost around $270.00. Make sure you replace both springs even though one is not broken.

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#64
In reply to #63

Re: Electric Garage-Door Motor Won't Run Under Load

01/04/2017 4:55 AM

See TonyHemet's reply #55 to my WD40 suggestion.

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#65

Re: Electric Garage-Door Motor Won't Run Under Load

02/02/2017 9:38 PM

I had the exact same issue with my garage door and it was super frustrating. In fact, my wife was at her ends with having to park outside and I am glad I found this post to help me out.

So, after converting to torsion springs, I guess I didn't update the motor lift settings which was messing with how it was running.

image source: https://www.garagedoornation.com/

I had a similar experience with calling liftmaster and they pretty much told me what they told you OP about getting help from them over the phone.

Luckily, I was able to whip out some things I learned from my engineering textbooks (we are talking WAY back in the day LOL) plus what I could find online including this post and this video to replace my springs

Hope this helps other home owners that were in a bind and may not have the engineering chops, but at least the DIY knowledge to make it happen.

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