What size trigger wires for winch solenoid - Maxwell HRC 6

[ozscott]

Hi all HRC 6 Maxwell unboxed today. Looks fantastic. It has a reversing solenoid and a switch. The solenoid goes up near the winch and is triggered by a dash switch. Min wire diameter is 6mm from batt and to winch but there is no indication of the up and down trigger wire size...they are spade terminals v pole terminals on the solenoid. What wire is suitable, just 2mm? Cheers

[Fed]

2 mm CSA should be fine but 2mm DIA might be a bit light.

Solenoids usually have a very high inrush current but after the iron core circuit closes the current drops to SFA.

Be aware if anything stops the magnetic circuit closing then the coil can burn out right before your eyes also overloading the control wiring.

Are the control (trigger) wires fused?

[peterbo3]

4mm will provide some fudge factor depending on the length of the wiring run. What does the wiring diagram/specs show as the solenoid amp draw? The 6mm seems a tad light for a winch. 6mm will handle about 50 amps, what is the max draw for the winch. If it is not shown, there will normally be a breaker/fuse size shown.

[ozscott]

Thanks guys. Max draw is 50 amp. I have heavier wire than 6mm on there now for the SouthPacific which is a much smaller winch but no solenoid. There is a circuit breaker to be installed near the battery and that's it. Cheers

[ozscott]

I just saw that cable length is from the battery to winch and back so that exceeds the 10m category which is 6.5mm squared wire and takes it up to the 10.5 or AWG 9. It does not give any specific size for the trigger wires. Cheers

[ozscott]

Another question... The diagram shows a spade terminal earthing back to the negative main wire from the battery. This is shown as a lighter wire than the battery wire. Can I just run this wire and solder it into the main negative battery wire going to the negative side in of the solenoid? Can't see why not. Cheers

[Fed]

I'm looking at the website & it shows a 3A circuit breaker for the control circuit.
cd.jpg

Is this what you're looking at?

[finga]

I'd be looking very closely to the size of the wire from the battery to the winch.
Even 10mm sounds very light for 50A at 5m route length especially if the wire is in any enclosure or bundled with other wires. Actually it sounds light if it was run in free air to me.
How far is it from your battery to the circuit breaker to the relay to the winch?
How is the wire run?? ie enclosed in a side pocket or cabinet or run along a shelf or run in the open, any other things with the wire?
All these factors affect how the conductor cools thusly altering the current carrying capacity of the conductor.

The wire can get to the 50A very quickly if the winch loads up and it does not take long for wire to heat up.

Cheers Scott
PS: I'd be going the 2.5mm cross sectional area or 4mm automotive for the trigger wires unless your boat is HUGE.
Better to be safe then sorry. Those relays are fairly expensive to blow up because of $5-10 worth of wire.

[Fed]

HaHa I found it again. Alt+253 = ²

Finga the website gives the power cable sizes subject the length and the circuit diagram calls for a 3Amp breaker on the control circuit so 2.5mm² would even be an overkill.
I only posted that to use the little ² sign.

[ozscott]

Thanks Gents - the circuit breaker provided is 50 amp. The wires will run up under the gunwales from the battery to the solenoid near the winch. It will run on top of the main loom and will have space above it, a few inches, but not below. So I would be better going heavier again than 10.5mm squared section...up another level or two. They recommend 10.5 mm squared, but I suspect the manufacturer wants to go with the easiest set up that will just get there. Rated output is 400W, so amps running would normally not exceed about 35, but presumably start up current would be higher. The wires on the winch motor are only about 3mm accross (diameter) but I dont want voltage drop from the battery which is about 6m from the solenoid.

Cheers

[Fed]

The 10mm² will be fine mate.
size.jpg

[finga]

This may be of use
http://www.rpc.com.au/pdf/efn133.pdf
You'll have to gauge yourself the ability of the cable to cool down if the 50A is applied.

Yeah, the 2.5mm may be overkill for the control circuit but when you consider that bigger wires are less prone to breakage from vibration and also less prone to failure due to corrosion or verdigris.
And it's easier to get proper sized terminations for the 2.5mm (4mm automotive) wire.

I wouldn't solder the negative control wire to the main negative cable from the battery.
Just use a ring terminal onto the main negative stud at the relay.

Cheers Scott
I can't get the alt+253 to work

[ozscott]

Thanks Finga - mate why dont they earth these solenoids internally? It seem odd to bring a wire out and then back, in effect, another external terminal...

Cheers and thanks again for your help Scott.

[ozscott]

Thanks Fed

[Fed]

Hold your Alt key down and hit 253 on the number pad. ²
Yeah 2.5mm² purely for mechanical strength.
Don't forget the 3 Amp circuit breaker ozscott.