Hello, I would like to discuss a plan for making charging system for service , windlass and motor starter batteries from multiple power sources: PV (on away missions) and mains (in ports).
Situation:
SmartCharger 12/30 3 outputs
MPPT + Solar panels - two sets, as two different PV panels types
Starter battery 90Ah (charged from alternator or SmartCharger)
Service batteries 240Ah (charged directly from MPPT, alternator or SmartCharger)
Windlass battery 100Ah (charged from service batteries via Orion DC/DC 12/12-18)
Here are my questions/concerns:
I would like to connect the third output to SmartCharger the windlass battery, but my concern is how to terminate the connection: before or after DC/DC charger?
Also what capacity should be entered in the BMV-700: just for the service batteries or also of the windlass battery?
Would it be wise to add additional BMV for the windlass battery?
I would like to connect the third output to SmartCharger the windlass battery, but my concern is how to terminate the connection: before or after DC/DC charger?
I would connect this to the house battery as this is larger, so 2 connections there, the DC to DC charger will then pass some of the current to the windlass battery.
Also what capacity should be entered in the BMV-700: just for the service batteries or also of the windlass battery?
Just for the service battery.
Would it be wise to add additional BMV for the windlass battery?
I do not think so because the windlass is only operated for short periods so it does not use much energy and it will nearly always be around 100% SOC.
Any suggestions to the schemat?
The scheme looks good. The DC to DC charger will charge the windlass battery OK and work well and limit the charge going to the windlass battery.
A lower cost option would be to use a voltage sensitive relay, but if the windlass battery is discharged then this would transfer a high current and not be as controlled.
Great! Thank you very much for your suggestions. I updated the scheme accordingly.
Is it what you had in your mind?
The distance between the service batteries and the windlass battery is about 9m, I will use 16mm2 copper cables do you think it will be enough? The voltage drop will be around 0,4V.
The voltage drop should be OK, as absorption continues the current reduces and the voltsge drop reduces so the battery does get up to the set voltage, just a bit slower.
