Advanced battery monitoring configuration

gyzko

What is the best way to monitor 4x 12V 110Ah GEL batteries?

Option A

With a 12V system using 1 "main" shunt and a dedicated shunt for each battery. In this case, we have

• main system voltage
• main system current
• current for each battery
  

Option B

With a 24V system using 1 "main" shunt and a dedicated shunt for each string. In this case, we have

• main system voltage
• main system current
• current for each string
• mid-point voltage for each string
  

Right now, my system is a 12V one. This is a power back-up system used in my home office in case of power outage.
On power outage event, there is approximately 22A draw from the 12V battery bank.

I already have one shunt and automatically tracking main system voltage and main system current.
I  have a DC clamp meter (Klein Cl390) and use it to manually look to current draw for each battery wired in parallel.

However, I want to make the monitoring aspect fully automated.

I am using Victron products and this ecosystem supports up to 5 shunts. Their shunt supports mid-point string voltage measurement as well.

The voltage drop in my system shunt is not significant. Around 2.1mV. So, I could afford to install more.

Switching to a 24 V system would provide the opportunity to install battery balancer. That could take care of battery balancing within a string.
However, it would not take care of the string balancing within the bank.

From a monitoring aspect point of view, which are the pros and the cons of each option? Does each configuration provides the measurements to quickly identify a battery failure (no matter which kind of failure we have in the system)?

Regards,

Francois

RCinFLA

If only drawing a total of 22 amps just one main shunt is fine.  Check the current distribution between the four batteries periodically with clamp on ampmeter.   If you get better then 20% variance between batteries consider it good.

If you where drawing a total of 75-80 amps then you need to be much for watchful of battery current distribution balance.