To avoid these ads, REGISTER NOW!

Putting multiple items on a single 20 amp circuit?

astrohip

Well-known member
Joined
Mar 7, 2015
Messages
338
Location
Brenham TX
I have a new horse barn with four commercial-type overhead doors (roll-up steel). The motorized operators for each door require 120v, 20 amp circuit.

If you knew you would never operate more than one door at a time, could you put all four on a single circuit? I would be doing this to save money, and to reduce the number of individual circuits. This is in the country, there are no codes, but I don't want to do anything stupid.

I haven't talked to my electrician yet, he's a good guy who won't do anything stupid either. I just wanted to gather some info before we meet to wire up the entire barn.
 
To avoid these ads, REGISTER NOW!

checkthisout

Well-known member
Joined
Sep 5, 2008
Messages
5,232
I have a new horse barn with four commercial-type overhead doors (roll-up steel). The motorized operators for each door require 120v, 20 amp circuit.

If you knew you would never operate more than one door at a time, could you put all four on a single circuit? I would be doing this to save money, and to reduce the number of individual circuits. This is in the country, there are no codes, but I don't want to do anything stupid.

I haven't talked to my electrician yet, he's a good guy who won't do anything stupid either. I just wanted to gather some info before we meet to wire up the entire barn.

Yes it's fine. I have 3 liftmaster commercial openers on mine and they all operate fine, even during simultaneous operation.
 

manwithtools

ALLIANCE MEMBER
Joined
Aug 24, 2015
Messages
13,645
Location
Lebanon, TN
No. The requirement is from me asking the guy who is going to install the openers what the elec needs are. He said 120v, 20a.

Sure he did, because that's what he's been told to say to everyone that asks that question. Ask him for the manufacturer and model number for the openers and then check for yourself what the actual current requirements are. If it really need a 20 amp circuit for each one, they would be 1.5 hp motors - not likely with any door openers we shop guys might deal with. If they were that big, they should be run on 230. More likely the are true 1/3 hp and draw approx. 7-8 amps continuous at max load.
 

Dick in Wisconsin

Well-known member
Joined
Mar 3, 2012
Messages
3,048
Location
Shawano, Wisconsin
Sure he did, because that's what he's been told to say to everyone that asks that question. Ask him for the manufacturer and model number for the openers and then check for yourself what the actual current requirements are. If it really need a 20 amp circuit for each one, they would be 1.5 hp motors - not likely with any door openers we shop guys might deal with. If they were that big, they should be run on 230. More likely the are true 1/3 hp and draw approx. 7-8 amps continuous at max load.

I agree. 2x. Look at the motor specs.

There is never anything inherently "wrong" with putting a motor on a 20amp circuit that can be safely run on a 15amp circuit.

By checking the specs on the motor, you might find that two of the motors can be safely run on a 20amp circuit and that should answer your question about four on one circuit (I would probably do it). I have one Liftmaster 8500 on a single 20amp circuit and I plan on putting two more on the same circuit.
 

BFBOB

Well-known member
Joined
Sep 20, 2011
Messages
5,073
The worst that would happen if two or more in simultaneous operation pull more than 20A is it'll trip the breaker. Make sure the WIRE's capacity matches the breaker (12ga for 20A) and you're safe. Maybe not convenient, but safe.
 

jim111

Well-known member
Joined
Nov 18, 2015
Messages
93
Location
tx
If you don't have the openers yet, you should google the electrical specs if you know the brand and model, just so your electrician can make an informed decision. Easier to get it right the first time than to fix it later. JMO
 
To avoid these ads, REGISTER NOW!

stangkid14

Well-known member
Joined
Dec 23, 2007
Messages
152
Location
Allentown,PA
I was literally just looking at my doors just a couple minutes ago for the same info. I have medium duty liftmaster openers for my 14'x12' doors and the tag on them said 6.6 amps. So i will be running 2 of them on a 20 amp circuit. my motors are 1/2 hp
 

nadogail

Well-known member
Joined
Jan 23, 2009
Messages
31,904
Location
Coronado, CA
Astrobiology,
I think you should be Ok with you proposed multiple door openers on the same 20 amp circuit.

I am not saying that I like the idea, but I am sure it will work fine.

My advice is guaranteed to be worth exactly what you paid for it.
 

theoldwizard1

Well-known member
Joined
Feb 22, 2011
Messages
43,076
Location
SE MI
I can imagine those four motors drawing 20A while running ! Now if you start them simultaneously, you MIGHT have a problem.

Door openers usually have some type of built in over current protection that would shut them down long before tripping a breaker.
 

md21722

Well-known member
Joined
Nov 30, 2015
Messages
1,840
Location
Mt Juliet, TN
I would guess that you can probably open 2 at a time on a single 20A circuit. If the controls for 2 doors are in arms reach of one person, you might consider running two circuits one for doors 1 and 3, and another for doors 2 and 4. That way if you have a helper over you can do multiple doors at one time without tripping breakers.
 

sberry

Banned
Joined
Jun 18, 2005
Messages
35,747
Location
Brethren, Michigan
Even big openers are only 3/4, most 1/2 or under and you will likely never run 4 at once. I have 4 that size, have never ran more than 2 at a time and wouldn't even need to do that except for I can
 
To avoid these ads, REGISTER NOW!
Top Bottom