Low and High Voltage cutoff Relay driver alternative to VIctron BMV-712

[Semievolved]

I have been looking and looking for some programmable device to activate high and low voltage cutoffs. The only thing I had found is the Victron BMV-712, which can only drive a single relay, thus I’d need two to provide over and undercharge protection.
https://www.morningstarcorp.com/wp-c...erOverview.pdf

I stumbled upon the RD-1 relay driver from Morningstar that will run 4, independent relays, and is fully programmable for cut-out and cut-in voltages. Additionally, each channel is diode protected. It sells in many places for $145 making it substantially less expensive than a single BMV-712. I'd use it the same as a Victron 712; to drive intermediate, small-draw relays, which would in turn drive the contactors that interrupt power to the battery or solar to the controller.

I’m on the edge of buying one for pending RV project and for my home. Any thoughts and feedback would be appreciated!

[Centex]

That looks very promising for providing the multiple voltage-related controls you seek, but the battery voltage data input that this device uses as the basis for its programmable logic must come from a compatible Morningstar Controller supporting their proprietary communication protocol, is that correct? [edit - NOT correct, see following post ]

It strikes me that while this provides expanded voltage-based relay controls for folks with compatible Morningstar controllers, it doesn’t 'substitute' for all of the battery condition and load-monitoring / tracking functions that the shunt-based Victron BMV-712 provides independent of other system components.

YMMV, but for me its those other battery condition and load-monitoring / tracking functions that prompt interest in the BMV-712. Even IF I wanted all the LVCO & HVCO automation you seek (I don't happen to see a need for that in my installation), I'd probably still want the BMV-712 too, for those other functions it provides.

[Semievolved]

no, the cool thing is that it doesn't need to be paired with a morningstar charger, it can work totally independent, just based on the voltage of whatever it's hooked up to. after i posted that, i realized it can also be used as a temperature, based cutoff or cuton as well using an internal thermometer. so, mounting this close to the batteries, i could use it to shut off charging and turn on heating pads if the temp falls below 35 F.



it doesn't have the SOC and Ah measuring functions of the Victron but i was looking for voltage cutoffs and, for that, it appears to be much more versatile than the victron.

[Centex]

Originally Posted by Semievolved

no, the cool thing is that it doesn't need to be paired with a morningstar charger, it can work totally independent, just based on the voltage of whatever it's hooked up to.

I stand corrected, Thank You!

I now understand that it bases its voltage controls on whatever the connected power-source driving the device, down to 8VDC, and that can be a (fused) connection directly to the battery

[RangerMan]

Look at 'Digi-Key'. They have just about anything you could want in control devices. Their tech support is top drawer! Tell'em what you're doing and they will find a solution.