Wiring Fuse panel/circuit breaker?

ntsqd

Heretic Car Camper
There are charts to look up the correct gauge wire/cable for a given amp draw and run distance. Those easily found on the net are for house wiring (AC) not automotive/marine DC. There is a difference, so dig a little. Marine sources are a good bet. I may have posted one or the link to one in the past. Don't forget to include the ground (return) path length as even if you aren't running a full length ground cable it does matter.
 

Tress

Adventurer
ntsqd said:
Don't forget to include the ground (return) path length as even if you aren't running a full length ground cable it does matter.

Do you mean don't forget that ill need that much more length of wire for the ground? I don't have to go all the way back to the engine compartment do I? I was figuring a ground to the frame just under the battery bank would be sufficient. Either way great info here, i finally received my copy of The 12Volt Bible so i have been learning a good deal from this post while i read that. Thanks agin and keep the info/opinions rolling, this place is fantastic!
:snorkel:
 

ntsqd

Heretic Car Camper
If it is a low current circuit then a frame ground is likely good enough. If it is a middle to high current circuit then the frame ground probably isn't good enough unless both grounds are tied to the exact same piece of metal. If the ground path would need to cross any welds then I'd run a separate ground.

With a separate ground cable it's length needs to be included in the total circuit length.
 

Tress

Adventurer
Ok well i think im just about ready to start ordering parts for my auxiliary batt bank and wanted to run the final plan past you all to make sure im not missing anything, and also ask a few questions.

First step- Run large gauge wire from starting batt under the hood to 40amp "batt to batt" digital charge controller inside the van near the aux batts. The run is around 18 feet long and im thinking I'll use around 1 or 2 awg cable with tinned copper eyelet terminals. Few questions, would a ground from the charge controller directly to the starting batt ground terminal be sufficient? Do i need a circuit breaker in this wire? Should this wire also be tinned copper?

Next step is connecting the charge controller to the (2) 6v Lifeline 300ah batts, the wire for this will only be about 4 feet max but im assuming it should be pretty big, maybe 1 or 2 awg, but the charge is coming from the 100amp alternator so im not entirely sure what size i should use?

From the aux bank i plan to run 4awg to the fuse panel which is around 4 feet away. Still not sure if i should use the fuse panels with ground or not though? Most of the circuits are just 12volt sockets and lights which i plan to ground on the frame but the biggest circuit will carry the air compressor which uses up to 28amps so im assuming i should run a ground to the panel for that one? I supose i could just get the panel with grounds and only use a few if needed?

Beyond that there is the solar panels with charge controller, batt monitor, power windows and the stereo that i'll need to wire. I'm a little unsure of what gauge i should use for the stereo, i know the power varies with volume and the run will be around 18feet! The panels should be pretty straight forward and until i receive the monitor i have no questions. Im thinking it would be wise to have the windows on the aux bank so they can be used when parked? One question here. So there it is, thats my plan, an abbreviated version at least. Please let me know if ther is anything glaring im missing and any tips reminders or ciritisism are welcome. After all the debate about criming soldering and terminations in general i might just bring the wire lengths to an electrician and have them make a nice connection! Although we did go and get a solder iron so we shall see. Anyways hope this all makes sense and once again thanks for any help or input.

:camping:
 
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goodtimes

Expedition Poseur
Tress, check into the cost of having someone crimp all the connections, and don't forget to include fuel costs (assuming you travel to them), and the hassle of going back and forth. You WILL make changes as you go...move things a couple inches this way or that way, etc., requiring you to change wire lengths, etc.

I picked up a decent criping tool that will handle down to 6ga for $50, and one of these for everything bigger:

990015.jpg


might be cheaper than paying someone else...
 

Tress

Adventurer
Believe me i have no doubt it would be cheaper to do the crimps myself but after all of the debate surrounding the issue im honestly a little intimidated to try. Since its such touchy subject im worried that as a first time crimper all my terminations will fall apart or something 100 miles down the road! Then of course there is the crimp vs solder great debate, overall im just nervous about it. But im with you and ill definitely do some comparisons, it would be so much easier to do it myself but again just not all that confident. Thanks for the input though, what do you make of the "plan"? I'm pretty comfortable with it all by now but im still curious about what other people would say. One of my most recent ideas was to have a second fuse panel on the other side of the van so instead of running everything under i would run something heavy over to he other side and terminate everything from that side there! Oh and i thought of another question, how do i determine what size wire to use for 12 volt outlets, i mean i can figure out what to use for 12volts but no sure what happens when you put a load on it, should i just run whatever works for 12V? Thanks again! Oh and how goes your project, sounds like we are in a similar boat here, maybe even cursing some of the same words at the saem time LOL! Take it easy and thanks. Oh one other thing are you using tinned copper wire or just plan ole? Late

:1888fbbd:
 
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BlueHZT60

Adventurer
I'm almost finished up with a similar wiring of my HZ60. Waytek is an excellent source for parts. Source a local wire supply & cable ends - you'll be making multiple trips.

I added a starter battery under the hood and cleaned up the dual battery wiring from the rear QP (2 years wired in parallel directly to the starter, with all loads off the starter bolt - it worked fine).

12 gauge is the smallest allowable wire for Emergency Vehicles. That should be a good hint for extreme uses.

I made a crimper with a ground down bolt/hammer. I also soldered & shrink wrapped everything. Any exposed wire was put in a loom also. (Yes, I'll need to monitor my wire ends for brittle wear/tear).

I added a circuit breaker panel for the Engle, compressor & Maggiolina Tent (which now has 12 volt heated mattress pad). I used separate circuit breakers for the winch and the inverter. I also fused both ends of the + wire running from the rear to the front of the truck.

Grounding may be my weak link & I'll be looking into a better ground situation for the winch.

Draw up a schematic based on everything you've learned and want to achieve - that will keep you on target as you start to wire everything.

Once I clean things up a little bit more, I also plan to run it down to my local Battery shop and have them do a thorough look through and correct anything I may have screwed up.

1/0 +&- cable rear bank to front (almost 20 ft) grounded to engine (for winch & Jump Start plug on front bumper)
2/0 +&- cable to Inverter (maybe 8 ft.)
4/0 + cable from starter battery to rear via ACM & circuit breaker
6/0 + to Engle w/body ground (don't melt the stupid cig plug when soldering)
2/0 + cable to winch
2/0 - cable winch to inner fender (will be changing)
2/0 - cable from starter to body & engine
12g +&- to Maggiolina & other Accessories

Tie down the wires, loom the exposed wires. I just spent a week on the road - no issues. The dual batteries lasted 2.5 days with inverter on (oops), Engle on 100%, Bed warmer used for 2 nights. Starter battery remained very happy.

Bob
 

Tress

Adventurer
Still kinda confused about a few thing!

First of all, when calculating wire size do i have to calculate the size for the distance to the appliance and back even if im not grounding at the panel? For example, if i have a water pump that uses 8 amps and its 10 feet away from the fuse panel do i calculate the size for 10 feet or twenty?

Secondly, how does one calculate wire size for a fuse panel? I assume it would be the size it would take to power everything at once. For example, if there was a potential of 100 amps on 1 panel and its 10 feet away then do i calculate the wire for 100 amps at 10 feet? And again with regard to grounding should the ground wire gauge be the same as the feed?

:ar15:
 

Tress

Adventurer
ntsqd said:
If it is a low current circuit then a frame ground is likely good enough. If it is a middle to high current circuit then the frame ground probably isn't good enough unless both grounds are tied to the exact same piece of metal. If the ground path would need to cross any welds then I'd run a separate ground.

With a separate ground cable it's length needs to be included in the total circuit length.

What constitutes a low med or hi circuit?

:REOutIceFishing:
 

goodtimes

Expedition Poseur
Tress said:
What constitutes a low med or hi circuit?

:REOutIceFishing:

He is referring to the amp draw on the circuit.

Low amp draw items are generally things that you would/could plug into your cigarette lighter....cell phone charger, GPS, etc.

High amp draw items are more along the lines of the air compressor, 2M radio, etc.
 

Tress

Adventurer
Thanks, so hi current would be anything over say 30amps? And another question, does the ground wire have to be the same size as the hot feed?
Thanks again, you done with your wiring project?

:REExeSquatsHL1:
 

ntsqd

Heretic Car Camper
If you have any doubt about the ground path then a grounding wire should be used and it should be the same size as the power wire. Wire gauge should be figured using the total length of the wire run (power & ground).

In really high current loads (e.g. battery at far end of vehicle from starter or winch) then a ground cable unconditionally should be used unless willing to experimentally determine whether it will still work in the worst case scenario.

If running a wire to feed a 100 amp fuse or breaker panel at a run distance of 10 feet, then those are the numbers that you need to find the correct wire gauge. Keep in mind that while you're pulling circuit power from the panel that the ground wire(s), if present, may have a different destination. So the ground wire length is likely to be different than the power wire length.
One way to deal with this is to install a grounding lug near the panel. Then the distances will be the same, but the wire running from that lug to the battery will need to be the same size as the panel supply wire, and it's length should be included when figuring the panel supply wire's size.
 

Tress

Adventurer
ntsqd said:
If you have any doubt about the ground path then a grounding wire should be used and it should be the same size as the power wire. Wire gauge should be figured using the total length of the wire run (power & ground).

In really high current loads (e.g. battery at far end of vehicle from starter or winch) then a ground cable unconditionally should be used unless willing to experimentally determine whether it will still work in the worst case scenario.

If running a wire to feed a 100 amp fuse or breaker panel at a run distance of 10 feet, then those are the numbers that you need to find the correct wire gauge. Keep in mind that while you're pulling circuit power from the panel that the ground wire(s), if present, may have a different destination. So the ground wire length is likely to be different than the power wire length.
One way to deal with this is to install a grounding lug near the panel. Then the distances will be the same, but the wire running from that lug to the battery will need to be the same size as the panel supply wire, and it's length should be included when figuring the panel supply wire's size.

We bought panels with the ground already on there so grounding to the panel is no issue, im just trying to determine what stuff should be grounded to the panel and what stuff can be grounded to the frame. If we ground everything then its going to cost a lot more, but just one other thing, if the wire length to the appliance is say 10 feet and im going to ground on the frame which is another 5 feet away then i should be calculating the wire size for a 15 foot run right?


Thanks agin!
 

ntsqd

Heretic Car Camper
I frequently use frame grounds, but that doesn't mean that I consider them to problem free.

Without knowing anything about your rig the safe thing for me to say is to ground everything to the panel, which should then be grounded directly to the battery. Varying from that is a judgment call. If the frame is a good conductor then everything can be grounded at the item. If not, then each item will need it's own ground run back to the panel or the battery, or to a known to be good grounding point.

Correct.
 

Tress

Adventurer
ntsqd said:
I frequently use frame grounds, but that doesn't mean that I consider them to problem free.

Without knowing anything about your rig the safe thing for me to say is to ground everything to the panel, which should then be grounded directly to the battery. Varying from that is a judgment call. If the frame is a good conductor then everything can be grounded at the item. If not, then each item will need it's own ground run back to the panel or the battery, or to a known to be good grounding point.

Correct.

Got it! A nuisanced response, love it! Sounds like I'll ground all the high'ish circuits to the panel which i plan to ground to the batt bank and then ground everything else to the frame. I know this is a touchy subject so i appreciate the help, and in case this helps i have a 1984 E-350 4x4 (pathfinder conversion) van.
 

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