Help with wiring a car lift...

[sevenstars]

First off I will start off by saying I am a newb when it comes to AC wiring, I am aware of all safety precautions and will have the power off when I'm attempting this and all my breakers, wiring, and switches are compatible.

Short story: I bought a used car lift and just finished installing it with only wiring and misc stuff left togo.

Here's what I'm working with:

Hydraulic pump motor: 2 yellow wires. One is labeled T1 One and the other is labled T4 Four

Momentary Switch: 3 terminals. They are labeled as COM with a 1 under it, NO with a 3 under it, and NC with a 2 under it

Wiring to box: 3 wires. Black, white, and bare

Wiring in box: 4 wires. Red, White, Bare, Black

If some one could help me with what wires to connect and where it would be great. Also what type of connectors would be best in this application?

 

[Charles (in GA)]

Some pics would help. Also, the info off the pump data plate, is this 120v or 240v?

Do you want to plug this one in and be able to unplug it, or is it to be hardwired in.

What brand, type, model, etc is the lift?

Charles

 

[sevenstars]

Some pics would help. Also, the info off the pump data plate, is this 120v or 240v?

Do you want to plug this one in and be able to unplug it, or is it to be hardwired in.

What brand, type, model, etc is the lift?

Charles

I can get pics tomorrow some time after my classes are over. It is an old Weaver lift Model number AFH-88A. And it is 240v that I plan on hard wiring into the wall
From what I remember off the pump data plate its a 2hp motor, 12.6 amps.
I'm running it on a dedicated circuit with a 20amp breaker.

Hope that helps, when it comes to having two hots and a neutral I just start getting confused

 

[sevenstars]

Since my camera is acting up let me rephrase my question another way:
The motor I am trying to wire is 240v

In a 240v circuit you have a 2 hot wires (Red and Black), a neutral (White), and ground (bare) Correct??

If I want to hardwire a 240v motor in general I would connect the ground wire to the electrical box on the motor then connect the red and black wires to the two leads coming out of the motor. Correct?

Now to put a switch in this circuit I would just add it to one of the hot wires. Correct?


Hope this is simpler. I tried understanding 240v wiring a little more tonight and this is my best stab at it

 

[Coastal]

You are on the right track, but i would think if you wired a switch to one of the hot wires, you would now just be turning off 120 volts, instead of the whole thing. Im wiring mine up this week too, but there are tons of wires as it was a 3 phase motor, im going to replace with a single phase....glad i have an industrial electrician for a friend!

 

[sevenstars]

You are on the right track, but i would think if you wired a switch to one of the hot wires, you would now just be turning off 120 volts, instead of the whole thing. Im wiring mine up this week too, but there are tons of wires as it was a 3 phase motor, im going to replace with a single phase....glad i have an industrial electrician for a friend!

Can someone else confirm this? If I had a switch on one hot wire when it was off there wouldnt be a complete circuit or am I wrong? Its only 110v if I am utilizing the neutral wire what I am not doing i thought...

Where/ how does the ground wire come into play in this situation?

 

[pattenp]

Since my camera is acting up let me rephrase my question another way:
The motor I am trying to wire is 240v

In a 240v circuit you have a 2 hot wires (Red and Black), a neutral (White), and ground (bare) Correct??

If I want to hardwire a 240v motor in general I would connect the ground wire to the electrical box on the motor then connect the red and black wires to the two leads coming out of the motor. Correct?

Now to put a switch in this circuit I would just add it to one of the hot wires. Correct?


Hope this is simpler. I tried understanding 240v wiring a little more tonight and this is my best stab at it

240V is just two hots, their is no neutral. You need to install a disconnect switch which will disconnect both hots unless your breaker box is in view of your lift and can be easily accessed if needed to cut the power. The momentary switch that operates the lift is connected on just one of the hots.

 

[pattenp]

Can someone else confirm this? If I had a switch on one hot wire when it was off there wouldnt be a complete circuit or am I wrong? Its only 110v if I am utilizing the neutral wire what I am not doing i thought...

Where/ how does the ground wire come into play in this situation?

Correct, there is no 110V with out a neutral. The ground plays no part in suppling the power, it's for protecting you form getting shocked if there is a wiring failure. It provides an easy path to earth instead of wanting to go through you to get to earth.

 

[sevenstars]

240V is just two hots, their is no neutral. You need to install a disconnect switch which will disconnect both hots unless your breaker box is in view of your lift and can be easily accessed if needed to cut the power. The momentary switch that operates the lift is connected on just one of the hots.

What drawbacks or problems that can arise with not having a disconnect switch? I never heard this mentioned before
My breaker box isn't more than 10 feet from my lift

 

[Charles (in GA)]

You should have an emergency disconnect right at the lift, easy to find, easy to operate (one of those big red buttons comes to mind) in case anything goes awry. The disconnect and any other switches, for safety should disconnect both of the hots from the equipment.

Charles

 

[pattenp]

What drawbacks or problems that can arise with not having a disconnect switch? I never heard this mentioned before
My breaker box isn't more than 10 feet from my lift

It's a code requirement. If I got the right code section it's NEC Article 430.102 b. I believe somewhere in the code it says your circuit breaker in your box can serve as the disconnect. Someone can step in to clarify this if I'm totally wrong.

 

[Charles (in GA)]

I said you should have an emergency disconnect, I didn't say you had to. If your panel is line of sight, less than 50 ft away, you do not have to have a disconnect at the equipment................. but................. you need something that stands out, easily operated......... by anyone............ and will kill the lift if something goes astray. The up/down switch could easily stick or malfunction, and on critical, safety sensitive equipment, it is always a good idea to have an emergency disconnect.

Charles

 

[Aceman]

I agree with Charles, while not required in this case it definitely isn't a bad idea. A box with a 2 pole motor rated snap switch and a couple of cord grip bushings really doesn't cost that much.

 

[sevenstars]

Thanks for all your advice guys, I wired the lift and finished up the hydraulics completely the other night and I took your advice Charles and bought a emergency disconnect switch too.

All and all it turned out great, the lift works and hopefully I'll have some pictures of it up this weekend.

 

[Junkman]

This begs the question ......... why don't lift manufacturers put the emergency switch suggestion into the wiring information. I had not thought of installing a emergency switch, but now that you mention it, I think it is a good idea. Any suggestion on a switch to use? thanks Junk...

 

[pattenp]

This begs the question ......... why don't lift manufacturers put the emergency switch suggestion into the wiring information. I had not thought of installing a emergency switch, but now that you mention it, I think it is a good idea. Any suggestion on a switch to use? thanks Junk...

I used a Square D DU221RB unfused disconnect. I have a two post lift and mounted the box on the post beside the hydraulic pump unit.

 

[Junkman]

I was picturing in my mind one of the red push buttons that you can quickly slam with your hand to stop the lift. Wouldn't this be better than the Square D DU221RB pictured below ?

 

[sevenstars]

I was picturing in my mind one of the red push buttons that you can quickly slam with your hand to stop the lift. Wouldn't this be better than the Square D DU221RB pictured below ?

When I was looking at switches to buy I bought a 30A g.e. switch similar to the picture you posted. I guess my main reason for getting it was the cost ($25 bucks plus fuses) verses the outrageous prices Grainger wanted for a push button switch. I guess its more of whats your budget and whats your preference...

 

[pattenp]

I was picturing in my mind one of the red push buttons that you can quickly slam with your hand to stop the lift. Wouldn't this be better than the Square D DU221RB pictured below ?

I'm sure there are better disconnect switches that can be used. I had this on hand so I used it. It does the job.

 

[rinny_tin_tin]

I was picturing in my mind one of the red push buttons that you can quickly slam with your hand to stop the lift. Wouldn't this be better than the Square D DU221RB pictured below ?

When tripping a motor or any inductive load, you have to consider the breaking current capacity - and one of those red palm switches can in no way compare with a Square D disconnect. For a red button emergency palm slap button to work in interrupting the current to a large motor, or even any system with significant current, the palm slap button operates as a pilot and controls a shunt trip breaker or a relay, etc. But you cannot put a palm-slap button (unless large and rated for such service) in series with say a 5 hp motor. However, it may work .......... once

 

[Vicegrip]

Guy in NOVA crushed in the top of his porsche 911 when his switch welded shut. The lift was in a lower level garage that had a center "I" beam and there was not enough clearance. He ran into another room to flip the breaker and listened to the car getting crunched before he could get to it. No disconnect. No overhead kill switch.

IIRC the Bend-pac instructions that came with mine had instructions to wire to code. Code dictates a disconnect/service switch.

I think the recommendations are the same for the Rotary and Challenger lifts at work. Im my dealer shops we have a switch right at the power pack that kills all the power before the control contact or. The Challenger in ground lifts use a relay that likes to weld shut. Not good. Mechanic stats lift up lets go of Up button and lift keeps going to the lock and the pump hits the internal pressure relief valve.

 

[krooser]

We need pix of your old Weaver... I have a ASH-90.

 

[sevenstars]

We need pix of your old Weaver... I have a ASH-90.

Sorry I'm taking so long lol, I've had classes from 10am to 8pm every day plus work in between, so I haven't been out in the shop to take new pictures but here's some teasers of when the shop was messier and before I cleaned up the lift, reassembled, and stood the lift up: