Best battery monitor for State of Charge (SoC)?

[ripperj]

If you end up with a Magnum inverter, they make a nice battery monitor that integrates well with their remote display, eliminates the need for another stand alone panel. It uses the same shunt as a lot of the other monitors

Sent from my Passport

 

[jeegro]

I think I have to get the Blue Sea. The interface is simply 100x better than the Victron, or any other monitor for that matter. Everything you need to know at first glance:

• Voltage
• Current flow
• State of charge %
• 2nd battery voltage

The historical monitoring is definitely a miss... but I think having all the above at first glance without switching between menu's is more useful.

And at ~$187, it's only a little bit more expensive than the Victron.

 

[DaveInDenver]

Where did you find it for $187? That's cheap.

 

[jeegro]

Hodges Marine

http://www.hodgesmarine.com/Blue-Sea-M2-Dc-Soc-State-Of-Charge-Monitor-p/blu1830.htm?CartID=1

 

[jeegro]

According to the specs, it measures 0.1A resolution from 0-100A, and 1A resolution from 100-500A. Is this with the included 500A shunt, or does the 100A shunt need to be fitted in order to get 0.1A resolution from 0-100a?

And should I monitor the negative flow of the starter battery, or just the AUX battery? ie. starter neg -> shunt -> frame or starter neg -> frame
I think if I monitored the starter batt, the SoC would get thrown off, since I should never really be depleting the starter batt, and the ACR disconnects them during discharging.

 

[DaveInDenver]

You need a shunt for each battery you wish to test. Electrically you could do a combined bank through one shunt but there'd be no way to know how much each battery supplied or got returned.

The reason for the resolution difference is the ammeter is apparently 3 digits. That means 99.9 and the decimal shifts to 100, either way there are 3 digits displayed. The ADC is probably capable of higher resolution, just what they chose to display for count and step size is larger.

 

[LeishaShannon]

I'd think thats on the 0-500A. However thats an order of magnitude less resolution than the Victron which measures down to 10ma. I'm not sure how that would effect accuracy of the SoC with small loads?

 

[Joe917]

And should I monitor the negative flow of the starter battery, or just the AUX battery? ie. starter neg -> shunt -> frame or starter neg -> frame
I think if I monitored the starter batt, the SoC would get thrown off, since I should never really be depleting the starter batt, and the ACR disconnects them during discharging.

You put the shunt on the neg side of the Aux battery and monitor SOC on the Aux only. The starter battery voltage is monitored as battery 2. Since the starter battery is at rest when you are camping voltage is a fairly accurate measurement of SOC.

 

[Tronix]

Another vote for the Victron 702. Works well for me. Not that I've used it yet, but read it can trigger a relay on low SOC condition.

 

[Rando]

Yet another vote for the Victron BMV-700. The user interface is far superior to the Trimetric and the bluetooth functionality is actually surprisingly useful.

 

[campo]

This is what the bluetooth Victron looks like