Replacing a remote with a switch -- voltage drop problems :(

[german_cargo]

I have a linear actuator that raises and lowers my snow plow blade and the wireless remote stopped working. Rather than order a new one for $200, I decided to splice into the wiring and put a momentary switch in my truck. I didn't like the remote anyways.

I grabbed some wire and wired up a 6 pole switch in a reverse polarity configuration and it works BUT it's really slow. The data sheet for the actuator didn't mention anything about voltage drop, it just said what kind of switch to use and to use 14 gauge wire. https://www.grainger.com/ec/pdf/Warner-Electric-Linear-Actuator-Data-Sheet.pdf

Obviously I need thicker wire. The online wire gauge calculator I used says I should use a 10 gauge, or even as low as 7 gauge if I want less than 1% loss.

My question is this:

The radio signal receiver / solenoid was only about 20 cm of wire from where it connects to the battery, and was thus a small gauge. Do I need to redo all the wiring straight from the battery posts? Or can I keep the existing infrastructure and splice into the smaller, 20cm long wires in order to regain the speed?

The actuator draws between 10 and 15 amps at 12 volts dc. It only has to lift the plow blade which weighs about 250 pounds. The data sheet says its rated to lift up to about 600 pounds which draws about 25 amps but there's no scenario where that would actually happen so I'm saying 10 to 15 amps is the operating range.

 

[Tom.G]

can I keep the existing infrastructure and splice into the smaller, 20cm long wires in order to regain the speed?

Yeah, that should work, IF you:
Either solder the connections or use screw-type connectors.

Even an extra 1/10 of an Ohm resistance will drop 1 to 1.5 Volts.

Also be sure to use a switch that is rated for DC operation with a motor load. At the instant of power application, the motor will draw well over the 25A full load current, I wouldn't be suprised to see 40A or 50A at startup. The switches available at you local hardware store won't handle that for very long before the internals melt and either act like a blown fuse or weld the contacts together. It could prove "interesting' if the contacts weld and you can't shut off the actuator.

One possibility is to open the existing controller and see if you can find the wiring to the relay(s)/contactor(s) that drive the actuator. If that is still functioning, maybe you can wire your remote switch to control the relay and not worry about the remote. The drawback of course is the down-time required could cost more than a new remote.

Cheers,
Tom

 

[Asymptotic]

Another option is to rewire the control switch to drive a high current winch relay mounted close to the actuator motor. Something like this ought to do. 150A surge, 75A (5 minute).

https://www.dbelectrical.com/products/winch-motor-reversing-solenoid-contactor-relay-6-terminal.html