Which inverter voltage input?

[Shark Bait]

3000/28=107.142 is stated spinning. Most 3k max at 5k= 178. I fuse 3k's at 300 amps all day long on 12 volt systems. Grounded inside the cab. They run pipe threaders. Been in for years.

 

[Shark Bait]

I use 1/0 wire with these 3k's as well.

 

[Skinny]

I agree with the 107 amps but that is assuming that the charging system is running. Current draw goes up to 125 amps if running off just the batteries. This is also assuming that the battery/charging voltage does not drop under load which it will. I'm going off of what the specs are. The unit says that peak output is 6000 watts which by your math is minimum of 215 amps which by mine is more like 250 amps with zero fudge factor for heat or voltage drop in the system. I'm not arguing your particular installations or whatever it is you do regarding inverters but I don't see this inverter being happy with that sized fuse protection.

 

[Keith_J]

Yes, it has a 100 amp charging system but you run 3kW inverter at its rated output and the voltage will drop as the alternators running at maximum output cause the rectifier bridge to heat up which drops output voltage. Then the regulator heats and the temperature compensation also drops voltage to prevent cooking the batteries.

Even at a steady 70 amp draw, the alternators in my 1031 drop to about 25.5 volts combined which is barely keeping the charge. It causes noticeable dimming of the headlights.

I have a MEP 026C, a 107 amp 28 volt generator. I hooked this up to the inverter, using the CUCVs batteries to smooth things out. It easily swung the load, keeping voltage at 28.5.

 

[Sharecropper]

Well, one thing is for certain - You fellas certainly know a lot more than I do about such matters.

This thread has produced some very lively and informative posts. I appreciate all of them. So I guess I will now ask the question -

What is the largest inverter my M1028 could run safely at 1000 rpm without overloading the CUCV 24v system?

 

[Skinny]

I would think a 2000 watt RMS inverter would be sized to not strain the stock system. Remember that is during normal operation. That size would peak around 3000-4000 watts which is going to load it up pretty good but in theory your peak only occurs for a short burst like a fridge turning on. What are you looking to run? Overkill is great but if you don't need anything past running some gadgets then your initial purchase and installation parts are going to make this expensive.

 

[Shark Bait]

Parts will cost the same for 3k or 2k.

 

[Shark Bait]

I agree with the 107 amps but that is assuming that the charging system is running. Current draw goes up to 125 amps if running off just the batteries. This is also assuming that the battery/charging voltage does not drop under load which it will. I'm going off of what the specs are. The unit says that peak output is 6000 watts which by your math is minimum of 215 amps which by mine is more like 250 amps with zero fudge factor for heat or voltage drop in the system. I'm not arguing your particular installations or whatever it is you do regarding inverters but I don't see this inverter being happy with that sized fuse protection.

The 150 is to safeguard the electrical system of his truck. He's not going to peak it at 6k long enough to blow a 150. If so, it's a fuse that is hurt and nothing else. The 6k is 500 milliseconds capable, according to the specs. Either way, a 2k or a 3k could be done safely and efficiently. ANL fuse, ANL fuse holder, ring terminals and 1/0 wire for each. Same cost.

 

[Keith_J]

I use a 150 amp circuit breaker, good enough for 36 volts so it runs fine at 28, besides the voltage rating is for arc extinguishing capacity. They care not what voltage they are run at.

I use another to protect the 80 amp 24 volt motor that spins the air conditioning compressor. It has never tripped, even with the huge startup load.

My 1031 has lots of electrical mods, so much I was contemplating installing a 50 amp 24 volt alternator off a MEP 802A. Just because alternators are easier to install than air conditioning compressors on an engine.