Questions!!!
I am installing a 2000 watt inverter and have most everything in place except the fuseblock and fuse. The installation booklet says to use 2/0 cable in 6 foot length, the lugs that came with it/no cables were sizes for 2 AWG I had a hard time inserting #4awg wire in them(confusion) they mention nothing about fuse sizing.
Is anybody familiar with this?
I plan on a second set of batteries strictly for the inverter, whithout solar, what is the best way to charge the batteries?
How would I connect to the house battery for charging without drawing from the house battery when using the inverter? The distance between the battery banks,10 feet,would require from my understanding 3/0 AWG cost prohibitive from my point.
Apreciate any help or suggestions about this.
Mickey
Correction, I reversed the sizes, I used 2 AWG and the lugs that came with the inverter were for 4 AWG.
The wiring all depends on how many amps you will be using with the inverter. If you are never going to use over 200 watts, then #10 gauge wire is fine with a 30 amp fuse. However that would be a waste of time and effort to limit a 2,000 watt inverter to only 300 watts.
If you are installing the inverter with #4 wire, then fusing that wiring to 100 amps is highly recomended, or #2 wire at 125 amps. I think that 00 wire is rated around 200 amps, but running two #4 wires will do the same job. So you might want to run #4 wire from each battery bank to the inverter and protect the wire with a 100 amp fuse near each battery.
I would pair all the batteries together, you will get the longest battery life that way.
There are two problems though. The usual and factory installed wiring between the 130 amp alternator and camper involves some #12 gauge wire and only a 20 amp fuse, and the wiring from the camper to truck is usually only rated at 20-30 amps with the ground barely able to carry 25 amps including the wattage used by the lights as well as charging the battery. Also the alternator typically has #6 wire connecting it to the truck batteries. (#6 is only rated at around 60 amps). Upgrading that wire to #4 will allow more power through the wire but might overload the alternator as well.
I would suggest installing a #6 wire from the alternator to a relay, then to a 50 amp circuit breaker (auto-reset) then to a heavy duty connector, then to the camper. This will allow the highest voltage to the camper batteries and the shortest recharge time from the engine running. The relay should be powered when the engine is running, so the same 12 volts that goes to the radio when the key is on will work to energize the relay. A three phase 30 amp rated receptical and plug will work to transfer the power to your camper from the truck. Being a twistlock connector, it can not be accidentally connected to a 240 volt circuit. Also it has 4 terminals, so you can use 2 for the ground and 2 for the +12 volt wires. With only 25 amps going through each terminal, you can have 50 amps going to the batteries.
The other problem is many people think they can buy a modified sine wave inverter and use it to power their microwave. I used my Trace 1,500 watt inverter to run my microwave a couple of times, and it never cooked as quickly afterwards, so I had to replace the microwave. Now I will only use my generator to run the microwave.
The amp draw while microwaving was about 150 amps, while my 4 golf cart batteries are OK with that much amperage, the voltage did drop over the 3-4 minutes we ran the microwave, then took a little while to recover the voltage. So with a starting voltage of 12.7, drawing 150 amps for 3-4 minutes, then the voltage drops to around 11.3, and will recover to 12.2 after a few minutes of little amperage use.
If you have 4 batteries and a sine wave inverter, then you can run the microwave. But if it is a modified sine wave inverter, I would not use the microwave on it. The A/C requires a pure sine wave inverter to run it, or motor damage will result.
Another problem that I see is when I am dry camping for a long time, I find that my 300 watt inverter actually uses less power to run the TV set than using my 1,500 watt Trace. So I usually just plug in the front TV and DSS to the small inverter and leave the large inverter off most of the time. The amp draw is only about 1 amp differance, but still over 24 hours it will make a differance. The larger inverter has bigger capacitors and larger transformer that will consume more power at a small load, and are less energy efficient at running a 100 - 200 watt load than a smaller inverter can do.
Fred.
PS: If you don't like generator noise (I hate generator noise and put my money into a solar system to prove it) consider a 120 watt solar panel. It will keep the batteries full while in storage, and will lead to much longer battery life.
Golden_HVAC wrote: Upgrading that wire to #4 will allow more power through the wire but might overload the alternator as well.
What do you mean by 'overload the alternator'? Won't it just put out max current, and no more? Alternators have to be rated for continuous duty -- don't they?
I've used 4 gauge wire with no ill effects, and am considering 2 gauge this time. I would think the bigger concern would be the battery max charging current rating.
SD00 wrote: Is anybody familiar with this?
I plan on a second set of batteries strictly for the inverter, whithout solar, what is the best way to charge the batteries?
I'm already doing what it sounds like you're planning on doing, here's a drawing of how mine's done---
I used 4ga for everything. The two banks of batteries are tied together at the inverter, so the inverter has a separate 4ga line feeding it from each bank.
The charging line I ran from the alternator is also 4ga, through an 80a breaker.
cewillis wrote: What do you mean by 'overload the alternator'? Won't it just put out max current, and no more? Alternators have to be rated for continuous duty -- don't they?
That depends on the specific alternator.
For example, the Ford 2G series used in the early 90's will fail at full load. The 3G and newer Ford alternators will run near full load without trouble.
The charging line I ran from the alternator is also 4ga, through an 80a breaker.
And you've never tripped the breaker? I used a 100a breaker before, and never a problem -- but I only had 2 batteries to charge.
I've only popped it a couple times, and that was when the batts were really low. They would take maybe 30 seconds of charge, then pop the breaker, but after just, maybe, 2 or 3 cycles as I recall, that brought them up enough to quit popping the breaker and they charged all the way back up normally.
What about the glow plug and start draw? Do either of those trip the manual breaker? I was considering putting in a disable tied into the glow plug circuit so it wouldn't connect to the camper batteries until after the glow plugs finished.
Offline
