Battery monitor or Solar controller?

[dmksails]

Right now I do not have a battery monitor on my boat. Neither do I have solar panels- I'm expecting to get them sometime next year.

Should I get a monitor now - something like a Victron BMV 702 - or will it become redundant later when I install panels and the required controller?

[john61ct]

There are some controllers that integrate well with a BM from the same vendor, but most are standalone.

That 702 is a great unit, get that now and down the road Victron MPPT controllers sized for your panels, all their gear ties together including free cloud logging, display long term trend charts.

[mohave_steve]

I am far from a solar guru but I have read repeated mentions over on the NW Arizona solar forum that the quality dedicated battery monitor are much more accurate than the "integrated" monitoring functions in most charge controllers.

As I understand it, the shunt that is used with the BM allows much more detailed monitoring of current flow in and out of the battery.

That makes a certain sense to me. The charge controller cannot tell if that current flow is going back into the battery or to power a load. The BM can.

[Mike OReilly]

Agree with John. All money well spent. The monitor tells you something slightly different than the controller. For the few hundred bucks, I like both.

Our system includes an older Victron bm, along with a new mppt controller. Both provide useful info.

[Paul L]

My BlueSky solar controller is also a battery monitor. It uses a shunt like the other amp counter style monitors.

[Dadrock33]

Originally Posted by Paul L

My BlueSky solar controller is also a battery monitor. It uses a shunt like the other amp counter style monitors.

Hey Paul - which model controller are you using? I'm in a similar "boat" (pun somewhat intended) in that I will have to use what I've got for right now but have plans (who doesn't?) to upgrade to a few panels and some house batteries. Been reading all the "stuff" for quite a while now and keep holding off as the technology gets better and better with each passing month (or less!!).

[Paul L]

Originally Posted by Dadrock33

Hey Paul - which model controller are you using? I'm in a similar "boat" (pun somewhat intended) in that I will have to use what I've got for right now but have plans (who doesn't?) to upgrade to a few panels and some house batteries. Been reading all the "stuff" for quite a while now and keep holding off as the technology gets better and better with each passing month (or less!!).

I have two 2512i units with a single control panel display.

[Madehn]

they will tell you slightly different things- my recommendation is the the balmar smart gauge for a monitor a- personally i use an outback flexmax 80 controller- it has worked well and they have a smaller flexmax 60 that is slightly less expensive-- both of these are pricey equipment but seem to both have good quality

[john61ct]

SmartGauge is best for accurate SoC

But it doesn't record AH in/out like shunt-based coulomb counters, eg Victron BMV-702

Many use both.

[barnakiel]

Monitor over a solar controller is only good when solar is your only source MIND that you do not have control over the OUT part of the power balance like this.

Get a decent power monitor like the BMV series. This will let you control both solar input and boat consumption. It is the better choice in a small system.

We have a Bogart. Great stuff.

Cheers,
b.

[john61ct]

The Bogart Trimetric, an excellent full-featured shunt-based BM, can control up to two SC-2030 solar controllers, total 60+A output.

I thought the WhizBang Jr setup was similar, not sure.