Where to buy power cable from in chch? & q on winch wiring

[Swaney]

Hey guys,

Thanks for your help on the winch plate mount - I went with the one from TM as it was just easier and im lazy.

Right - have found out im short on power cable for my removable winch setup.. so my next question is where do you guys purchase your cable from?

I know I need some flexi 50mm wield power cable (rated at 450amps at 80% duty cycle) but where from?

Also do you need to wire the negititve lead back to the battery terminal or can it just be earth mounted on a chasis point? (lookin at saving one length of cable at least lol)

the setup is gonna be worth more than the actual winch lol

[meatc]

BOC is a good place to start for cable, and 50mm would be the min you want. I would run the earth to the battery.

Your winch will draw at least 500amps at full load with good clean 12v power. As the volts drop the amps increase, little cables / poor earths create voltage drop. More amps equals more heat generation, more heat equals more resistance equals more voltage drop equals more amps equals more heat etc etc.

the fastest way to kill your winch motor is baby cables and poor earths. Remember the power in the earth is exactly the same in the positive.

Just for info my WC zuk runs a 6.5hp warn motor on an 8274 and I run 95mm2 cable, and 2 small truck battries (bigger than ns70) and we winched out of a creek at Manukau, had the engine die, so winched about 20+ m up hill into the finish box with no drama. Big batteries and big cable for reliable winching

[flyingbrick]

There would be nothing wrong with running a second decent cable from your battery's negative to the chassis- and then running the negative from your winch to the chassis.

This also makes sense because your winch can potentially be mounted on the front OR REAR of your vehicle. You don't need to run an earth all the way to the back of your truck.

Every electrical failure I have seen has not been in the cable but it has been in the joint between the cable and whatever the cable is joined to. EG have had jumper leads smoke where the clip is crimped to the wire, and the same on a corroded + winch terminal.

Cut the cables to the right length then take the cables into an electrical place (boc may do it?) and get the correct sized lug crimped onto each end (they will use a hydraulic crimper)

The hardest part for you is going to be finding a decent male and female plug system so you can disconnect the thing easily!

[Swaney]

Thanks for the heads up.. BOC is miles cheaper than where I was looking (radcliffes).. $19 for 50mm per meter or $28 for 70mm per meter.. i think i will run with the 70mm..


and (edited 5 mins after first post) - will use the battery earth to chasis and winch mount to chasis for earthing - makes good sense in my mind.. cheers flyingbrick



The connect / disconnect system I am using is a big heavy forklift battery connector thingy.. was told it was good to 500amps

looks like

[suzolla]

Personally i would run cable for both positive and earth, if for some reason you get a high resistance between the battery and the chassis the current will start flowing through the earth to the starter and then anything between the motor and the chassis and body.
Cheers
Tim

[darinz]

You can use the chassis as the earth BUT the problem is getting the power from the cable to the chassis. Also you will definitely need to have a cable from the earth terminal on the winch motor to the chassis.
So I would suggest you have an earth from the winch motor to your plug as well. The make sure you have large surface area where the cable meets the chassis. The problem is steel isn't a good conductor so while the chassis has huge potential, the small surafce area where the cable conects to it doesn't. You have to plan on 500amps going through that conection after all.
And also run a seperate earth to the chassis so you don't overload the existing earths.

[Swaney]

Yep 500amps is a fair whack eh.. I think i will; just bite the bullet and run the negititve cable back to the battery terminal.. will mean an extra length of cable but them the brakes i guess.

also was gonna put in a battery selector switch for sending power to either front or rear of truck as well as having it all isolated.. something like http://www.trademe.co.nz/Trade-Me-Motor ... 771438.htm

would be nice to have this dash mounted but will prolly end up being mounted somewhere under the hood.

[rokhound]

Now where do you get those? and are they highly rated?

I am running 2 x 1000cca batteries on my 12000 pound winch and that is just the sort of switching I was looking for.

[Swaney]

Most marine places - seems that the big grunty boats use high power DC as well

721 - HEAVY DUTY SELECTOR SWITCH is what you want - google I got my link from http://www.bepmarine.com/home-mainmenu- ... tor-switch

Cost about $100 per switch


Specs below

The 721 Battery Selector Switch is our heavy duty selector
switch. Housed in the same module as the 720, it includes the
same removable plates and back cover. While BEP Marine
recommends isolated battery systems as outlined with our
distribution clusters, the 721 offers a simple economical way of
separating two batteries.
Please note selector switches will not separate
electronics from harmful engine starting spikes.
721 Specifications:

* Continuous Rating: 350Amps DC between common B1 or B2
* Continuous Rating: 500 Amps DC between common B1 + B2
* Intermittent Rating: 500 Amps DC
* Cranking Rating: 1500 Amps DC
* Voltage Rating: 48 Volts DC
* Operation: Selector-Battery 1-2-Both-off
* Mounting: Recessed or surface
* Termination Stud Size: 3 x 10mm(3/8")
* Tin plated copper studs and nuts
* Dimensions: 102 x 102 x 90H (4 x 4 x3.5H")
* Ignition protected

[darinz]

You can use there smaller standard switch that is about $40. It has surge rating (10 seconds or less) of 1250amps, intermitent (up to 5 minutes) rating of 455amps and continuous (30minutes) of 275amps.
The reality is you can't supply enough power to heat these up anyway. 455 amps for a 5 minutes is a lot of power and it is likely your motor would die first anyway. The battery power required to supply this sort of power is mind blowing as well.

Lets put it this way. I've been running those switches with both 6hp Warn motors with 24v powering then and with 7.8hp Superduty motors. The 7.8s drawn well over 455amps and the only time I had a switch problem (well it caught fire) was when a terminal on it was loose.

But bigger is better so if you have the space use the bigger ones.

[Swaney]

http://www.smartmarine.co.nz/701s-mini- ... -5943.html

one of those type ones you mean?

$60 saving is $60 saving after all!

Cheers for the heads up

[darinz]

Do you need a 4 position switch? I used the same size but the standard 701 on / off only.

[Swaney]

yep.. thought about the 701 but then i figured when it is on both the back end and front end would be live.. where as if i use the 721 then i can direct the power to front or back only as needed..

but yea it prolly wouldnt matter having both ends live as such...

fingers cross in the next couple of weeks or so i will have it all wired in and winching.. will post pics when i do!

----------------------

Edit - ended up buying this switch for $66 inc postage


Cranking Rating: 10 sec. 2,000 Amps
Intermittent Rating: 5 min. 600 Amps
Continuous Rating: 350 Amps
Maximum Voltage Rating: 32 Volts DC
Terminal Stud Size: 3/8"-16 (M10)
Terminal Stud Torque: 140 in-lb (15.82 Nm) max.
Mounting Holes: Accept 1/4" (M6) Screw
Cable Size to Meet Ratings: 4/0 AWG (95mm)
Cable Clearance For 4/0 AWG Cables 1.10" (27.9mm)
Weight Lb (Kg) 1.15 (0.52

[darinz]

Where from that looks like a good deal?

[Swaney]

http://www.trademe.co.nz/Members/Listin ... er=3448354 - that member there flick them an email at info@aquatech.net.nz and they will send u details or auction link.

Was $60+6 postage.

[rangimotors]

Now where do you get those? and are they highly rated?

I am running 2 x 1000cca batteries on my 12000 pound winch and that is just the sort of switching I was looking for.

they are really good, I used the same ones and you can mount several together, I had 3 in a row for various dirrerent power supplies and kill switches. You can also pull the knob off completlet when in off mode so that no one can start it etc. I got mine from a mate who services boats. I'm sure I could ask him who they buy them off or how much they get them for.