Solar and engine charging

[gettinthere]

I have an ARS 5 balmar regulator on my engine alternator and a Blue Sky 2512 on 280 watts of solar.
Might the solar output into the battery bank be fooling the balmar regulator, causing low output from the alternator?

With 85% state of charge I usually get around 70 or so amps but with full sun today I was seeing only 45 amps net input. Voltage was in the mid to high 13 range

 

[Maine Sail]

I have an ARS 5 balmar regulator on my engine alternator and a Blue Sky 2512 on 280 watts of solar.
Might the solar output into the battery bank be fooling the balmar regulator, causing low output from the alternator?

With 85% state of charge I usually get around 70 or so amps but with full sun today I was seeing only 45 amps net input. Voltage was in the mid to high 13 range

Unless your solar can supply 45A it sounds like the ARS-5 was in voltage control and likely would have been shutting down the Blue Sky.. Perhaps the batt mon needs a re-sync or the ARS-5 went into float prematurely.. Next time that happens watch the scroll on the reg and see if it is bulk, absorption or float..

Is it possible you had a large DC load running?

 

[Q22]

I used to use my truck to charge my RV it didn't charge a lot of amperage.I put a cut off switch between the truck battery and the alternator and it charged much better.Your probably on the right track.

 

[Bill Roosa]

all those control devices are voltage sense controlled. So it kinda depends on where each is sensing is input control voltage. The alternator regulator should have a voltage sense attached to the house bank and the solar is connected internally inside the box. The solar should be connected directly to the house bank also so it is effectively sensing the house bank unless you have a long run of undersize wire from controller to bank. These are typical setups so you need to check. things to look for are isolation diodes between the house batteries and the voltage sense wire(s), and undersize wires causing a voltage drop between where you sense and the batteries
If the solar are putting out 14.4 volts the alt regulator will think the batteries are fully charged after it does its start up routine. Most external regulators start out at 14.4 volts and then power off after a few minutes to test the "resting voltage" (please dont flame me I know that is not actually correct but don't know what else to call it) and determine what to do next. The time the regulator shuts off the alternator is when things can get mixed up with the solar boosting the voltage and tricking the regulator into thinking the batteries are fully charged.

 

[Maine Sail]

all those control devices are voltage sense controlled. So it kinda depends on where each is sensing is input control voltage. The alternator regulator should have a voltage sense attached to the house bank and the solar is connected internally inside the box. The solar should be connected directly to the house bank also so it is effectively sensing the house bank unless you have a long run of undersize wire from controller to bank. These are typical setups so you need to check. things to look for are isolation diodes between the house batteries and the voltage sense wire(s), and undersize wires causing a voltage drop between where you sense and the batteries
If the solar are putting out 14.4 volts the alt regulator will think the batteries are fully charged after it does its start up routine. Most external regulators start out at 14.4 volts and then power off after a few minutes to test the "resting voltage" (please dont flame me I know that is not actually correct but don't know what else to call it) and determine what to do next. The time the regulator shuts off the alternator is when things can get mixed up with the solar boosting the voltage and tricking the regulator into thinking the batteries are fully charged.

The ARS-5 is monitoring the voltage many hundreds of times, per second..... The easiest way to solve any voltage battles, at high states of charge, is to simply set the alt reg absorption voltage 0.1V - 0.2V higher than solar....

 

[JohnShannon]

Sounds OK

280W panel in full sun is going to be pumping out 20A. So in the dark you get 70A from the alternator in the full sun you get only 50A from the alternator and 20 from panel still 70 to the battery.

Do you have a preference for hydrocarbon derived electrons?

 

[gettinthere]

John
My Victron reads the whole ballgame. If I'm getting 70 from the alt and 20 from solar Victron will read 90...minus any draws from refer, etc.

My ARS is set a 10th or 2 higher than the solar controller.

I might have another opportunity to check tomorrow. Ran lots of stuff today including the flatscreen (snowbowl!) so I'll be in the low 80s tomorrow...

 

[gettinthere]

My 2 balmar ars 5 settings are 14.3 and 14.8

With soc of 78% I'm getting around 80 amps out of a 100 amp alt. Voltage is reading 13.25. Partly shaded panels on a sunny day. (and 80 degrees )

You are in bulk....

 

[gettinthere]

I think I found the issue.

I was set for 14.7 bulk and 14.5 absorption...at the minimum times!
So I was getting 6 min of bulk, 6 min of absorption and then going to float.

The programming is a real PITA. I did get it right on the voltages back when I programmed it but evidently the duration settings did not 'take'.

I set bulk to 1.5 hours and absorption to 6 hours and then shut it down, powered back up and double checked voltages and duration.

We shall see...