How many amps is the breaker for your four post lift?
 

I am in the market for a four post lift. All the makers tell you the volts of the motor (120 vs 240) but none of their sites tell you how many amps are needed. So can you guys please tell me how many amps the breaker has for the circuit you use for your lift, the volts for your motor (can you wire your motor for 120 or 240) and the brand and model (if you know it) of your lift?

I want to make sure I have enough juice to run the lift I buy without adding wiring.

Thanks

Chuck

My 2 poster is a 240 volt motor. I ran a double pole 30 amp breaker. I ran 12/2 wiring. The motor is a 2 HP and pulls 19 amps at max power.

I have a 4 post, Autolifters I bought used (hardly) 220 volt. Listed amperage is 19.5, and the motor is rated at 3 HP. The previous owner installed a long power cord, and I just plug it into the dryer outlet just inside the house from the garage. The wife hasn't complained yet...

What brand is your lift?

I am about to add two 4-post lifts and am wondering how many amps they pull at 120v. I'm not in any rush to raise the cars, they are just being stacked for storage, so 120v is all I need.

Good rule of thumb is a 120v motor will draw twice the current of the same HP motor on 240v. If it draws 19.5 amps on 240 it'll need 40 amps on 120v.

Mine is a Direct lift purchased from Greg Smith equipment. www.gregsmithequipment.com

I agree on the 120 volt. They pull twice as many amps as a 240 volt. I don't care how fast or slow you want it. Check the motor rating it will tell you the amps. 240 is not hard at all to wire up

Just some general electrical information. You should only load a breaker to 80%, so if the lift is drawing 19.5 amps, you should use a 30 amp breaker with #10 wire. #12 wire is only good for 20 amps, and should only be protected with a 20 amp breaker.

Im running my Eagle 4 post lift on a 120 volt 15 amp ground fault circuit with no problems at all.

Ditto. I have been running my Direct-Lift for 4 years on 120V, 15amp, grd-fault circuit with absolutely no problems. Motor/pump combo seems to run free with no real load noticeable. Using a short light duty extension cord to the wall and cord stays cool to the touch.

Andy

Are you sure that's correct? I thought it will still draw only 19.5 amps, however, when run on 120 v it gets all 19.5 amps on one power wire. When run on 240 v it splits the amps between the two power wires, therefore, it uses 9.75 amps per power wire.

At least that's the way I understood it when I converted my air compressor from 120 to 240. It sure made a difference when it was cold in the garage.

No electrician here but I did stay at a Holiday Inn last night. I think you are half right. Using a double pole breaker on a 240 volt I thought the 19 amps was split in two so you had 9.5 amps on each.

If you are running it on 120 volts the amps will double to 38 and you would need a 50 amp breaker to be safe and bigger wire.

Electrical Power
 

I looked at several lift mfg. web sites, 4 post storage, 4 post lifts, 2 post lifts.
Most did not list the complete motor specs. HP, Amps, Voltage.
some were 1 HP, 1.5HP, 2HP and 3HP, I would think that 1HP & 1.5HP could be run on 120/208/220 volt, but the 2, 3 & 5 HP units would need 220 volt due to the amps.
Most electrical tech books list that.

Figure about 1400 watts per horsepower.
Divide Watts by volts to get Amps, for example:
•3hp motor, 120V
•3hp X 1400 W = 4200 W
•4200 W / 120 V = 35 A

I am an electrician. With any piece of equipment, the wattage it draws always stays the same, no matter what voltage it is hooked to. The higher the voltage, the lower the amp draw. Any equipment hooked up 240, will draw half the amps of equipment hooked to 120. If the lift can be hooked up 120 or 240, it should also tell you the amp draw at both voltages. One advantage of hooking it up 240, is that you can run smaller wire and use a smaller breaker. Just remember that you don't want an oversized breaker. It needs to match the wire you run, to protect the wire.. 15 amp for #14 20 amp for #12 30 amp for #10

After reading your response I went out and checked. I was going off memory before, not a good thing. I did run #12 wire and a double pole 20 amp breaker for my lift. The run is quite short as the lift is within 6 feet of the circuit box. Was I correct in the amps being split by running a double pole 20 amp breaker for a motor that peaks at 19 Amps for 240 volts?

At 19 amps 240 volt, you should basically see 19 amps on each pole (phase) of the breaker. At 120 volts, you would see 38 amps on a single pole breaker. Generally you wouldn't load a breaker to more than 80% of its rating, so with a 19 amp load, a 30 amp breaker with #10 wire would be ideal, but a lift doesn't run continuously, so a 2 pole 20 amp breaker with #12 wire, will work fine for this application. Basically, the circuit breaker is not for equipment protection. Its protection against the wires burning up.Thats why the breaker amp rating should never be larger(there are exceptions) than the amp rating of the wire.The lift motor should have built in protection. Hopefully that helps.

Yes that helps. As I recall I asked specifically what amp and wire I should use and went with their recomendation. It runs a maximum of 45 seconds at a time. :cheers:

I bought a 110v lift from Greg Smith Equipment and it's on a 20 amp circuit.

cc

Is that the Direct-Lift? And are you happy with it? It's one that I'm considering.

An 80% rated breaker means that after 3 hours there will be enough heat to cause a bi-metallic breaker to trip at 80% load. So in the case of a lift that would only run a few minutes at a time going over 80% load would be fine. One thing to think about is circuit protection is really product protection.