How many watts is your inverter when cooking food in your truck.

Resistive heater elements, motors all have a momentary HUGE power draw. For example a device like a microwave, or your electric burner may normally pull 1,000 watts in operation, but for the first second they may draw 1,500 or 2,000 watts of power. BTW, your small fridge is probably only pulling 100-200 watts, but the moment the compressor starts it will demand almost twice that much and then settle down to the normal power use. Inverters are always rated for both a "peak" power draw and a "continuous" power draw. I suspect when you plug-in your burner and turn it on your 2 devices are demanding more power momentarily than your inverter can supply so a circuit breaker in the inverter pops. One thing you can do, is run your truck engine. If your power demands are right at the ragged edge of what the inverter can supply, supplying the inverter with 14 volts from a running truck electrical supply instead of the 12 volts from battery only while engine is stopped MIGHT help you. It depends on how much the total power demand of your devices is compared to your inverter. Generally, it's best if your power inverter "peak" rating is TWICE what you expect to normally use. This peak capacity is usually enough to deal with what is called the "in-rush" that motors and resistive heating draw during the first fraction of a second.

 

Motors yes, they'll pull significantly more at start without a soft start. Resistive loads are pretty consistent though. Resistive heaters do have a bit of change through their temperature range, but not nearly as much as you're implying.

 

Ok. Thanks.

 

That current surge is called "Locked Rotor" and in the case of a refrigerator starting up it can be somewhere around 2400+ watts for a very small fraction of a second. In buildings, most circuit breakers are designed not to let this trip a breaker. Even if there is nothing else on the circuit that 2400 watts is going to strain almost all inverters.

I am not going to attempt here to explain why this happens in detail. I will attempt a quick and dirty explanation though. When an AC motor is off basically there is a dead short because there is no inductive reactance (electrical resistance). Once the motor gets up to full speed the inductive reactance causes resistance.

 

And it's a pretty simple fix by putting a capacitor on it. But hey it cost a few cents for each motor so...

 

2500 watt puresine. But i only run 1 big thing at a time. I have a 0 guage appliance extension cord rated for 5000 watts i just swap between devices as needed and replace anually. Main engine runs if doing my microwave and when i HAVE an APU (this will be fixed soon) i use that for everything else.

 

Just want to clear something up. Is that 0 gauge used to supply the inverter with 12 volts? Keep in mind that 5,000 watts at 120 volts is about 42 amps whereas 12.8 volt 5000 Watts nigh on 400 amps. The amps is what makes the heat in the conductors.

 

Your thinking a diffrent cable, i.e battery to truck. im talking literal extension cord, inverter to microwave for example. Standard 120v plug.

Picked these ones up at the farm supply place and i cant find the exact one online but its a 6 foot 0 guage outdoor cord rated 120v x 15 amp upto 5000 surge for 5 minutes and 1875 continuous. Its intended for running from a generator to a trough heater. But it works great for a microwave.

 

2500 to 3000 watts continuous run should meet your needs. Usually an inverter has a surge rating of twice the continuous output rate. When installing, use 0 gauge wire and keep the run as short as possible. Also, make sure you have a fuse at the battery connection. Some inverters need a secondary ground connection. Mounting it properly will help, plus it should have good cooling air flow around it.

There are two types of inverters, modified sine wave and pure sine wave.
Not going to get into details here, too long. Just do a search on modified vs pure sine wave.

Pure sine are worth the few extra dollars. Your electrical equipment will last longer, run cooler and work better.

some electronic devices do not like modified sine wave power sources.
They just will not work, or work well. Microwaves are a good candidate for this.

if you have any electronics, like a laptop, with an external power supply. Check how much heat is generated when used on an inverter, versus a land line outlet. You might be surprised at the difference.

 

That's why I was asking to verify what the cable was used for because 0 gauge is something I've never heard of for an extension cord. 15 amp extension cords are typically 14 AWG. Microwaves should only draw about 1,200 w so anything more than that is really overkill.

Depending on your situation and how often you park in a yard for a weekend or longer there are inverter chargers which would allow you to have a shore power plug setup to run your 120V devices and keep your batteries topped up while not running the motor. I drive a company truck and leave it on the weekend plugged in with the espar heater running so my water doesn't freeze. I don't have to worry about the batteries dying if it's plugged in. The International LT I run came with an Eaton but no need to go that far. It seems most people these days recommend Victron.

https://a.co/d/92z45AS
I've been looking at this for my sailboat.