New volvo and solar panels

[Jules W]

Hi
I have a problem. It's very minor but irritating. My new d2-75 has it's own dedicated starter bank. I thought it would be sensible to connect solar to it to keep the batteries topped up. Yesterday I tried it for the first time and almost immediately the battery warning indicator and accompanying high pitched alarm went off. It would seem my victron blue solar mppt is triggering the too high voltage alarm. The simple solution is to put a switch on the solar positive so I can turn it off. But is there a way to reduce the charging voltage to say 14v? Probably too complicated!

 

[Tranona]

not sure why you would want solar to your engine start battery as if your charging system well organised it is charged immediately after every start and should be fully charged unless you leave it for a very, very long time unused. I assume you already have a means of connecting your house bank to the engine to start it in the unlikely event of the start battery suddenly failing.

 

[Baggywrinkle]

IMO, Connect your solar to your house bank, and put one of these between the house and engine bank. A Cyrix-CT 230A ... https://www.victronenergy.com/upload/documents/Datasheet-Cyrix-ct-120A-230A-EN.pdf ... then wire up the "connect" button to enable starting from house batteries and starter combined.

The device will connect the banks together automatically when there is a charge voltage present and disconnect them when there isn't - it can replace your diode or FET battery isolator normally attached to the alternator, then run your alternator direct to your starter battery.

In my boat it looks like this ............

 

[Jules W]

Thanks. You are right that I don't really need to but I have two small 12v solar panels which don't add much to my domestic array. The starter is 12v and the domestic 24v. Separate alternators in place. I think I will just bin them.

 

[VicS]

Hi
I have a problem. It's very minor but irritating. My new d2-75 has it's own dedicated starter bank. I thought it would be sensible to connect solar to it to keep the batteries topped up. Yesterday I tried it for the first time and almost immediately the battery warning indicator and accompanying high pitched alarm went off. It would seem my victron blue solar mppt is triggering the too high voltage alarm. The simple solution is to put a switch on the solar positive so I can turn it off. But is there a way to reduce the charging voltage to say 14v? Probably too complicated!

Yes you can adjust the absorption and float voltages See the manual for the solar controller. Check the voltages first though with a reliable multimeter to be sure they are causing the alarm.

.

 

[philwebb]

Thanks. You are right that I don't really need to but I have two small 12v solar panels which don't add much to my domestic array. The starter is 12v and the domestic 24v. Separate alternators in place. I think I will just bin them.

Hi Jules, don’t bin your solar panels! I’ll take them off your hands. (Assuming that you’re not too far away!)

 

[PaulRainbow]

Yes you can adjust the absorption and float voltages See the manual for the solar controller. Check the voltages first though with a reliable multimeter to be sure they are causing the alarm.

.

Easier said than done with the BlueSolar controllers, they need a VE Direct to USB cable and a windows PC running Victron Connect to change settings.

 

[William_H]

Simple answer is to connect a small solar PV ie less than10w direct to the engine battery or via a PWM controller. The low power from solar PV should mean never get really high voltages at battery but will keep battery happy. Use the MPPT and Pv for the domestic battery. ol'will