I purchased a dedicated 280 amp alternator for my Sprinter van. It is so I can run an air conditioning unit via a Victron 3000 alternator/charger while I'm going down the road. There will be situations where it will run constantly for hours. The unit will draw as much as 2000 watts on a continuous basis. Does anyone see any issues with overheating or durability?
if the Air con currently starts ok with the multiplus and its under the multiplus max load conditions then as long as you keep the multiplus within its temp limits by having good air flow. this in my opinion should be fine.
I assume you are talking about an inverter/charger?
Assuming you are talking about a multiplus 3000, just keep in mind that the AC output drops as the unit heats up. If heats up too much, output will drop below 2000w regardless of how much DC power is available from the batteries and alternator. You can look at the victron data sheet to see the ratings at various temps, but this is something you'll probalby need to figure out from real-world testing. This is where you really want as much air circulation around your inverter as possible.
Besides the alternator, you don't mention what your battery bank looks like. If the alternator can constantly deliver enough amps, it may not matter. Just remember that a 280a rated alternator will not always be able to deliver 280a. Same as the inverter, they will typically throttle the output back as they heat up. Also, it's not likely to produce anywhere near 280a at idle even when cool. All this is really related to your alternator specs, so it's worth looking at.
If you have a decent battery bank that can supplement the alternator output, it wouldn't matter if the alternator can't push all those amps continuous or not. That's typically the way it works. The inverter is just pulling DC amps. If the alternator is producing plenty, it's providing power to the inverter and hopefully charging the battery at the same time. If the alternator isn't producing enough, the inverter is pulling all the available amps from the alternator and whatever else it needs from the battery. So, as long as your alternator is keeping up on average, it's OK if it can't constantly put out the amps because the batteries take up the slack during those times.
Finally, you don't mention anything between the alternator and inverter/batteries. If you are saying all the alternator output is available to the inverter, I'll assume it's an straight connection to a house battery bank that the inverter is hooked to. That can be OK in some situations, but not OK in others. It's probably OK if your secondary alternator/regulator is smart and configured for your battery type, etc., but definitely something you want to think about if there are any questions.
Thanks for the thorough response. I have a Nations alternator that should be plenty capable of continuous output. It should be able to power the inverter and have enough left over to charge the batteries (we will almost always be driving or on shore power). It puts out 200a at idle which will be rare for us. It will go directly to a bus bar and then to the inverter and to a 200a AGM battery bank via a b2b charger. I think I've decided to put in some additional 12v cooling fans from AC Infinity which I'm also using for my stereo cabinet. They are thermostat controlled and will move a lot of air.
Thanks again
What b2b charger are you using and what is it rated for? If I'm understanding you correctly, you are planning to connect the main DC bus bar to your alternator, but the bus bar is only connected to your battery through a B2B charger? That's a very unusual configuration because I don't think you'd be able to run your inverter (or other DC loads connected to DC bus bar) from battery power when the alternator isn't running. That would also mean any charging from your multiplus (when on shore power) would have to go through the b2b charger to charge your batteries. Sorry if I'm misunderstanding your setup, maybe it's the more traditional setup and I'm just reading it wrong.
Typically, your battery would be connected direct to the DC bus bar (inverter as well) and the b2b charger is connected between the alternator and the battery bank. Think of the house battery bank as the "lake" where everyone goes to drink (get power). The b2b charger, solar charger, and inverter can all dump water (power) into the lake. The inverter/charger is a little unique because it can provide and take power, but hopefully that all makes sense.
Hi, I would use an inverter air conditionning, you will reduce incredibly the amount of energy needed. Mine at home uses around 500W at the maximum power, and works flawlessly 24/7 during june,july,august. You won't stress your alternator, nor the multiplus, neither the battery bank.
Michel
