I am going to install an inverter in my trailer and am curious about what gauge wire I need to run from the batteries. To be honest I really don't have an application or device I want to run off it. I just want to do it for the "because I can" factor. I plan to mount the inverter against the front wall of the trailer so I don't imagine more that ten feet of DC wiring from batteries to inverter. Below is what I have to work with since I already own them.A Zamp 2000 watt pure sine model ZP-2000ps. What gauge wire would I need to get optimal use from this? (Figure 10 feet from battery to inverter). This is the one I'll probably use as this is what I had in mind when I bought it.ora Zamp 600 watt pure sine model ZP-600ps. What gauge wire would I need if I decided to install this model instead. (Figure 10 feet from battery to inverter).Is voltage drop a concern in this kind of setup, or is that mostly a concern with solar installs?Thanks

10 feet is 5 feet too many for a 2000 watt in my humble opinion. Remember round trip, whatever your wire length is, double it, since you have a positive and negative wire, and the electricity flows through both. Voltage drop is a very real concern especially under heavy load.For my 2800 watt 4000 watt surge inverter I used 4-ought #0000 welding cable, 12 feet total round trip which includes 6 feet for the cable linking four batteries in parallel.Keep your DC cables very short and use an extension cord at the output to get AC where you need it.

Ampacity and voltage drop are always a concern.zamp seems to have a very brief manual with no specific install instructions.https://www.zampsolar.com/manuals-and-instructionsI recommend 4/0 wire for the 2000 watt and #4 for the 600 watt. Probably 250 amp fuse and 100 amp fuse respectively.http://www.genuinedealz.com/custom-cables

Look up the manuals for some other 2000w inverters and see what they say you need, then do that with yours. Hint: A 2000w inverter loaded to 2000 will pull 200 amps from the battery bank (use the "divide by 10 rule" which also covers efficiency losses)EG, I have a 2000w inverter that says to use a 500amp ANL fuse and 1/0 wire up to 6 ft and 3/0 wire up to 10 ft. Over 10 ft they say to call their tech support.Other 2000 w inverter specs say use a 250 fuse instead of that 500 but apparently the 500 is to cover for the inverter's surge rating of 4000w. Anyway you do know you need to fuse for at least 200 amps on the wire.On 2000 vs 600, note that the 2000 will run everything (some one at a time) like your microwave, toaster, kettle, etc. The 600 is too small for many things but will do the television etc. For running the fridge on 120v going down the road, people have learned that a 600 is marginal for that too--a 1000 does work for that.

Some of us have gone to 24 or 48 volts to lessen line loss and use thinner, more flexible wire.opnspaces wrote:Is voltage drop a concern in this kind of setup, or is that mostly a concern with solar installs?Not sure what you mean there...solar wiring is a different subject.

What gauge wire from batteries to inverter | Good Sam Community

SoundGuy
Explorer
Jan 27, 2018
LittleBill wrote:
pictures above are auto resetting circuit breakers, not sure why we think they are terminal strips

SoundGuy wrote:
On second blush I think you're right, question is what they're for. :h One is easy - the small sofa slide - but the other wouldn't seem to serve any purpose as there's already an auto resetting CB in the positive line coming from the battery that goes on to feed these two CBs, the inputs of which which are jumped together. I'll have to take a closer look once I get the trailer out of winter storage.

LittleBill wrote:
i would hold off replacing or rewiring anything till you have a stronger understanding of how things are wired here.

Obviously :R ... which as I already said I can't do for awhile yet as my trailer is currently in winter storage. ;) Once I do have it back here at the house it'll be a simple matter to identify just what each circuit does and why it's wired the way it is. Between now and then, if I happen to drop by my dealer I'll take a look at a new 192RBS. :)
LittleBill
Explorer
Jan 27, 2018
SoundGuy wrote:
LittleBill wrote:
pictures above are auto resetting circuit breakers, not sure why we think they are terminal strips

On second blush I think you're right, question is what they're for. :h One is easy - the small sofa slide - but the other wouldn't seem to serve any purpose as there's already an auto resetting CB in the positive line coming from the battery that goes on to feed these two CBs, the inputs of which which are jumped together. I'll have to take a closer look once I get the trailer out of winter storage.

it most certainly has a purpose, the wires are different gauges the cb's are also different amperage's, since the main cb is rated higher, the branch off circuit breaker is using a smaller gauge wire, thus it will need to have a smaller cb(which i assume it does) to protect the branch wire, same as a main and branch breaker in house hold wiring

i would hold off replacing or rewiring anything till you have a stronger understanding of how things are wired here.
SoundGuy
Explorer
Jan 23, 2018
LittleBill wrote:
pictures above are auto resetting circuit breakers, not sure why we think they are terminal strips

On second blush I think you're right, question is what they're for. :h One is easy - the small sofa slide - but the other wouldn't seem to serve any purpose as there's already an auto resetting CB in the positive line coming from the battery that goes on to feed these two CBs, the inputs of which which are jumped together. I'll have to take a closer look once I get the trailer out of winter storage.
LittleBill
Explorer
Jan 23, 2018
pictures above are auto resetting circuit breakers, not sure why we think they are terminal strips
SoundGuy
Explorer
Jan 23, 2018
SoundGuy wrote:
Typical of many travel trailers mine has these awful terminal strips mounted on the trailer frame just below the front pass through storage compartment.

I'm going to take this opportunity when installing the new G31 AGM to replace those strips with this 7-way weatherproof junction box I bought at Princess Auto today.

My plan is to connect the inverter to the battery with 12" to 18" of 1 or 2 gauge pre-made battery cables, then cut my existing 6' lengths of 4 gauge that had been running from the inverter to the battery on the tongue and instead wire those to this new junction box which will be directly below where the new G31 will be sitting. This will really clean up the entire setup, protect those terminal connections from the elements, and minimize voltage drop between the battery and inverter. :B

mapguy wrote:
Fyi, that 7 way junction box is for trailer light/brake wiring and probably won't support the amps of an inverter as listed.

The inverter wires aren't going anywhere near these terminals but directly to the battery. You're absolutely correct though, this box is intended for light / brake wiring but the size / weight of the threaded studs are exactly the same as those terminals already in use. That said, none of this may matter as the more I look at the above pic the more I'm beginning to believe those aren't just terminal strips but rather auto resetting circuit breakers. I'll know for sure once I take a look but the trailer is in winter storage right now so it'll be awhile before I can verify just what I'd dealing with.
mapguy
Explorer
Jan 23, 2018
SoundGuy wrote:
BFL13 wrote:
SoundGuy, putting an AGM in there will also reduce your tongue weight so you can carry more heavy things in the truck. Or you could use that space for more propane bottles.

Yeah, that actually may be a downside as I'm currently only running ~ 13% gross tongue weight as it is and would prefer a bit more ... with a new G31 AGM sitting in the pass through instead of the A-frame that will only worsen the situation. :( I've been considering what I could put in that empty battery box sitting on the tongue but just haven't come up with anything yet. :h I could rearrange the A-frame platform again and put the propane tanks back where they originally were just aft of the tongue jack but I much prefer this setup as it is. Gonna have to muse on this a bit more. :p

Typical of many travel trailers mine has these awful terminal strips mounted on the trailer frame just below the front pass through storage compartment.

I'm going to take this opportunity when installing the new G31 AGM to replace those strips with this 7-way weatherproof junction box I bought at Princess Auto today.

My plan is to connect the inverter to the battery with 12" to 18" of 1 or 2 gauge pre-made battery cables, then cut my existing 6' lengths of 4 gauge that had been running from the inverter to the battery on the tongue and instead wire those to this new junction box which will be directly below where the new G31 will be sitting. This will really clean up the entire setup, protect those terminal connections from the elements, and minimize voltage drop between the battery and inverter. :B

Fyi, that 7 way junction box is for trailer light/brake wiring and probably won't support the amps of an inverter as listed.
babock
Explorer
Jan 23, 2018
pianotuna wrote:
I'll have to tell my 700 watt heater that it has no inrush the next time it refuses to operate on a 750 watt inverter. I'll threaten to spank it.
You are correct. A typical heater circuit can have up to 25% increase in inrush current due to to heater element having a much lower resistance when cold until it reaches operating temp. It's not as much as an inductive motor startup current but it's still there.
SoundGuy
Explorer
Jan 21, 2018
pianotuna wrote:
I'll have to tell my 700 watt heater that it has no inrush the next time it refuses to operate on a 750 watt inverter.

Surge demand caused by an inductive load that can be many times running current is a different animal than inrush of a resistive circuit which is cold and is only a small percentage greater than it's average running current.

It appears the 1000 watt PSW from Canadian Tire is still lonely. I.E. it is their only PSW unit.

Yep, and still a good deal for what it is even though it's on-sale price has gone up, like everything else. ;)
pianotuna
Nomad III
Jan 21, 2018
I'll have to tell my 700 watt heater that it has no inrush the next time it refuses to operate on a 750 watt inverter. I'll threaten to spank it.

It appears the 1000 watt PSW from Canadian Tire is still lonely. I.E. it is their only PSW unit.
SoundGuy
Explorer
Jan 21, 2018
pianotuna wrote:
Inverters with switched power supplies (all of the cheap units) need to have a higher rating--because their ability to surge is pretty lousy. If a 2k unit is only a few bucks more than a 1k unit--I'd deliberately oversize the component.

Maybe, depends on what you're using it for, what's available, and for how much $$$. Mine is a 1000 watt PSW from Canadian Tire, in reality an NPower inverter, purchased because it's was the only PSW inverter sold at the time by CT and because the sale price of $199 for a PSW of this size couldn't be beat here in Canada. :B Secondly, the only inductive loads my inverter sees is a 30 watt fan so obviously the inverter's surge capability is a non-issue. Both my toaster and coffee maker are resistive loads so surge isn't really an issue with those either. ;) Bottom line - I don't care about an inverter's surge capability and therefore have no need to buy "over" my needs.

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