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Topic: how to monitor house rv battery or batteries (Read 591 times) previous topic - next topic

how to monitor house rv battery or batteries

These will be my next purchase.  I especially like the phone app.  Battery Monitor BMV-712 and the Battery Protect 12/24V-220A  Anyone out there using these or another brand of battery monitor or low voltage cut off? 

I've thought of this before and now will do after seeing this entertaining video at AM Solar. https://www.youtube.com/watch?v=BJyjRUErSi8
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: how to monitor house rv battery or batteries

Reply #1 –
I am thinking about buying that monitor as one of my upgrades when I get the solar on. As far as a low voltage cutoff, my Zantrex sw3012 has that feature built in. The inverter draws the most power from the battery in my case and shutting it down would let the batteries recover to a non damaging state. I don't have enough 12 volt items running at night to worry about. This is dry camping info. I don't put the coach in storage without power which might make the device useful.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: how to monitor house rv battery or batteries

Reply #2 –
Compare prices at Bay Marine Supply.  Alan is a Forum Member.
Victron Energy BatteryProtect 220 Amp

I have 2 BMVs, a 700 and a 702.  The 712 adds built in Bluetooth.  The others use an add on interface.  Mine are all integrated into the Victron CCGX control.  These work well.  High quality equipment.

Make sure you understand how the low voltage cut off switch works.  It has smart time delays built in to prevent inadvertent shutoffs.  One ahould hope this is never really needed but sometimes they are.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: how to monitor house rv battery or batteries

Reply #3 –
Quote from: craneman –
I am thinking about buying that monitor as one of my upgrades when I get the solar on. As far as a low voltage cutoff, my Zantrex sw3012 has that feature built in. The inverter draws the most power from the battery in my case and shutting it down would let the batteries recover to a non damaging state. I don't have enough 12 volt items running at night to worry about. This is dry camping info. I don't put the coach in storage without power which might make the device useful.

Yes craneman, probably the low voltage device is not needed by me neither.  I'm just thinking, for $120, pretty good protection for my 3 8D AGMs.  2004, FMCA, Redmond, OR. after show lot sale.  Fellow co worker salesman unplugged my Monaco Signature rv and plugged his in.  I came back a week later to 2 wasted brand new Lifeline 4Ds and a refrigerator with $150 in moldy meat and other food.  The battery monitor, I've already run the wire for when I installed the solar last year, as recommended by AM Solar.
97 U295 40, Build #5040, 6C8.3 325 HP
Oregon Continuous Traveler
Samsung Residential #RF20HFENBSR,
Xantrex SW2012, (3)AGM8D Hse, (2)AGM Grp24 Eng, Victron BMV-712, 1800w Solar 4 LG & 2 Sunpower
Extreme Full Body Pt w/hdlmps, new furn/floor, 4 down Lexus 2004 GX470 AWD curb weight 4,740 lbs
Prev: 1990 Barth, 10L 300 2 yrs; 91&92 Monaco Signature, 10 yrs, 10L C 300 &  6C8.3 300; 1997 ForeT 6C8.3 325 since May 2017.  Employed by Guaranty RV 14+ yrs.  Former VW New Car Dlr/Service Dlr, Sales Mgr, Rv Sales, and Service Adviser from 1968-2017
"Don't criticize what you can't understand" Bob Dylan

Re: how to monitor house rv battery or batteries

Reply #4 –
I am a novice when it comes to most electrical work, so before writing this, I reviewed the wiring diagram Vicrton has online. My question is-When  installing the BMV-700, 702, or the 712, with the intention of monitoring both the House batteries and the Starter batteries, where do you suggest mounting the Shunt? If I understand the wiring diagram correctly, a large negative cable would need to be routed to the shunt from each set of batteries? Thank you in advance
wiring diagram  https://www.victronenergy.com/upload/documents/Quickinstallsheet_BMV70x_part1_2.pdf

2000 U270 34' WTFE Build 5756 "Ole Red"
2014 Honda CRV
Washington, Vermont
Lady Lake, Fl,  Independence, VA
Former owner of 2002 U320, 2003 U320, 2005 U270

Re: how to monitor house rv battery or batteries

Reply #5 –
The shunt is located between the negative side of the batteries and the connection to the rest of the ground side of things.  The shunt is measuring a very small voltage drop across a known resitance to get the current flow across the shunt.  So it needs to go between the batteries and the rest of the negative connections.

Think of all of your batteries connected together as a set.  They act as one bigger battery.

If your house batteries and start batteries have the ground posts connected from one to the next and then on to a longer ground cable then the simple thing to do is get a short ground cable, 3/0 or 4/0 size, connect that to the last battery post on one end then the shunt and then the original ground cable.

If you have a common bus bar the shunt needs to go between the bus bar and the negative cable.

The two photos show the shunt at the house batteries.  The second one shows the shunt after the common negative bus bar and then out to the negative cable.  The batteries and negative cables to the bus bar have not been installed in this photo. The third shows the two BMVs installed along with the Victron color control and two line voltage meters.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: how to monitor house rv battery or batteries

Reply #6 –
Roger, Thank you for that explanation and for the pictures. I have a much better understanding now
2000 U270 34' WTFE Build 5756 "Ole Red"
2014 Honda CRV
Washington, Vermont
Lady Lake, Fl,  Independence, VA
Former owner of 2002 U320, 2003 U320, 2005 U270
 

Re: how to monitor house rv battery or batteries

Reply #7 –
Thanks.  Let me know if you need some additional help.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN