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nkingy2003 avatar image
nkingy2003 asked

Can I add a switch to the Victron 700 battery monitor so that it isn't constantly on?

I'm adding a Victron 700 battery monitor in to my boat system. From what I understand, the positive to the shunt is supposed to be connected directly to the battery, presumably to get the most accurate voltage reading.

My problem with this is that the boat will be left for weeks on end and with no way to turn the battery monitor off, I don't want it to drain the battery whilst the boat isn't being used.

I am going to have a battery isolation switch, so I could put the shunt positive on the other side of this switch, but I guess this could affect the accuracy of the reading. Alternatively, could I put in a switch in the positive cable between battery and shunt?

BMV Battery Monitor
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2 Answers
seb71 avatar image
seb71 answered ·

You can just remove the in-line fuse from the BMV positive wire.

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Kevin Windrem avatar image
Kevin Windrem answered ·

You probably do NOT want to turn off the battery monitor. When powered down, the monitor will either reset to 100% SOC when turned back on or wait until the battery is fully charged before giving any SOC or remaining time/AH indication.

The BMV-700 has less than 4 mA idle current. That calculates to 2.9 AH per MONTH. The BMV-172 and SmartShunt have 1 mA idle current so 0.7 AH per month. I think you'll find that these idle currents are much less than the self discharge currents of lead-acid batteries and if running lithium the resultant drain won't be a factor for many months. For example the 700 will only drain a 100 AH battery to 65 % SOC in a YEAR.

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