With nine phase alternator it doesn't need much if any DC supply filtering.
Question that you should find out is how it is doing regulation. There are several possible ways depending if it is permanent magnet rotor or slip ring field winding current regulation. It can be a combination of motor speed and electronic regulator.
From a fuel consumption point of view you don't want a fixed engine speed. It will usually get less fuel efficiency if loaded less then 40-50% of engine hp rating.
If I was to take a guess, I would say it probably works like an inverter generator in ECO mode. They have permanant magnet alternator that produces DC voltage from rectified multiphase AC alternator output. The DC voltage depends on engine speed and electrical load. The regulator likely keeps engine speed high enough with some amount of overhead DC voltage margin that fine voltage regulation to output is done with switching power supply regulator.
The generator DC output is smooth enough to run your inverter directly without any batteries connected, as long as you don't go over 150A's.
Question is whether it is just a fixed limiter current (150A). You have to be sure when your battery is low the generator does not put excessive charging current to your batteries. Make sure you monitor charge current. If it is fixed at 150A (until voltage regulation) you are pretty much screwed for small capacity battery. Check around the electronic regulator to see if it has a current limit adjustment.
The application of this generator was for grid backup of cell site so may not have been intended to charge batteries. In the worse case the generator shuts down if load exceeds 150A and it cannot maintain the regulated voltage output.
It you destroy your batteries the generator won't be such a good deal.
Does it have provision for a remote current sensor?
Without one, it couldn't know if it was charging battery at 100A, or if load was pulling 90A and battery was charging at 10A.
Sunny Island knows when power comes from AC, because it decides how much to push or pull from DC.
When a DC charge controller is used, Sunny Island knows either from battery shunt or data link if the charge controller supports one. But, Sunny Island doesn't tell DC charge controller to adjust current during bulk charging; it only switches bulk/absorption/float mode and voltage limits.
So as I add DC charging I'll limit available current by the amount of PV attached to charge controller. Sunny Island can see that and provide additional charging from grid or AC coupled GT inverters.
But, Sunny Island doesn't tell DC charge controller to adjust current during bulk charging; it only switches bulk/absorption/float mode and voltage limits.
Propane, and 4 gallon tank for 8 hours. More money than I'd like to spend if ongoing on a monthly basis, OK for power failures. Natural gas cost is preferable. Does it run on both?
Now if you can just capture waste heat, use for water and domestic heating in the winter ...
Batteries definitely care about charge current, and it is up to you to stay within what they can handle. Excess current can harm them, and overheating does too. Charge controllers usually have a temperature sensor, because charge voltage needs to vary with temperature. Even in cars - the old regulators for generators adjusted according to ambient temperature.
You should find some way, perhaps a maximum RPM, to keep the generator from charging your batteries at higher current than their data sheet allows.
My SunXtender data sheet says initial inrush current has no particular limit, could even be 5C, if other limits are observed. Some people here question whether that is valid, suggest the battery could be harmed by high current.
The voltage setpoints of the generator may also limit current enough.
My familiarity is with AC generators as DC generators seem pretty rare to start with, but I just found some surplus ones that put out 48v DC. It just happens to match my battery bank perfectly; which is feeding the house via SMA Sunny Islands.
Before I jump on the purchase, I just wanted to confirm as there seems to be conflicting information. My plan is to utilize the Sunny Islands to control the generator - on/off and prevent overcharging. Since they're the same voltage as the battery bank, I don't need any step up or step downs. Do I need anything to control that charge rate?
Is there anything I'd need specifically? Or is it really as simple as - hook it to the battery to replenish the bank?
Thank you,
Your Sunny Island wants to control the generator based on it's calculated SOC measurements - won't your system which appears to be triggered only by voltage, just crank up every time you put 4kw or better load on your SI because it sees a voltage drop? Most of the 48VDC generators I found were 48V power supplies and not regulated battery chargers. I did see a few that were, but they cost more than my Onan 8kw Quiet Diesel inverter generator! I suppose you could shut down the on-board system and control it with one of the relays on the SI and an Atkinson GSCM generator start module, to keep the SI happy.
We tried something similar to this with our system and found that all the juice needs to go thru the shunt attached to the SI, but ultimately found the lack of regulated 4-stage charging to be a deal-breaker.
Sorry, didn't see this thread was old and that you had already taken delivery. Please keep us updated as to your success with this. Curious, how much did it cost if you don't mind me asking?
That is a fantastic price! Good score!The generator was $1500 delivered. There aren't a whole lot of brand new generators available at that price point, lots of used ones in unknown condition though. I felt it was worth the risk at that price point.