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Wiring for switch to hydraulic lift table.

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Bobby D.

Mechanical
Jun 4, 2021
1
Hello,
I bought a used 120V Autoquip lift table with no up / down switch. There are 4 wires that go to the missing switch box, but I cannot get the lift to move at all if I connect the wires as if bypassing the switch box? Do I need a specialized switch or is there a way to determine if this lift works before I shell out the money for the switch/ foot pedal. Thanks
 
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There are several different ways this thing can work so we're at a loss as to what to suggest. Have you got any kind of schematic? Got a picture of the motor plate?

Keith Cress
kcress -
 
Find out which model and then download the manual.
Which model is it?
What colours are the wires?
Do any of them have volts on them? If not check your power supply.

White appears to be power
, black is up, red is down and green is ground.

If you connected white to green you've probably blown a fuse...
Start from power in and check where the power stops.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
 
The wires go somewhere. Find out where they go.

If it's like most small hydraulic lifts, for "up", power goes to a motor that operates a small hydraulic pump, and for "down", power goes to the coil of a single-solenoid spring-return normally-closed valve.

The motor, and that valve, will have wires going to them. Find them. Check wire colours. Check continuity with wires that show up somewhere else. Check continuity through the motor, check continuity through the valve coil. Check that the motor actually works. Check that the valve actually works.

Check for over-travel limit switches, particularly for "up". The valve normally won't care if the valve is left open after the platform hits bottom, but the motor and pump might care. If it has an over-travel limit switch ... check continuity through it, and make sure it actually works.

It is not a complicated machine ... even if it has an over-travel switch.
 
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