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redtoad asked

Use Smart Shunt as sensor for BMV-702

I am partway through piecemealing a transition from lead-acid batteries to solar/lithium power on a 15 year old motorhome. I have already ordered a 500A "Victron Smart Shunt", selecting it primarily for the Bluetooth function. But having a fulltime display inside the coach would be nice. I have been offered a BMV-702, without a shunt. (But if I tried to add a BMV shunt, in addition to a Smart Shunt, don't I create a problem? Can they work "in series"?)


I have seen on this forum that the BMV-702 may be used with various sized shunts. It seems to me, this hinges on connecting a circuit board for the BMV to the "sense screws" on the shunt, not the communication network link. Maybe I got that wrong, and the rest of this doesn't matter!


Does the Smart Shunt have accessible "sense screws" like the shunt provided with the BMV's? Alternatively, both the BMV-702 and the Smart Shunt seem to have a Victron VE.Direct networking cable terminal. Does either of these allow the BMV to accept current detection from the Smart Shunt?

Thanks again for helping me determine the suitability of Victron components in my system.

BMV Battery MonitorSmartShunt
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2 Answers
klim8skeptic avatar image
klim8skeptic answered ·

@RedToad Does the Smart Shunt have accessible "sense screws" like the shunt provided with the BMV?

No. However the SmartShunt does use a 500a / 50mV shunt.

Alternatively, both the BMV-702 and the Smart Shunt seem to have a Victron VE.Direct networking cable terminal. Does either of these allow the BMV to accept current detection from the Smart Shunt?

You have 2 options. Buy a complete shunt (including the pc board) for a BMV 702 / 712 and put this in series with the SmartShunt, then run the rj11 cable to the 702 display.

Or get a replacement shunt pc board for a 702 /712 and carefully drill and tap holes on the back of the smartshunt to mount the pc board to. Run the rj11 cable to the display. Do be careful.

smartshunt-50mv.png

shunt-example.png

Do not use the pc board part# as this is for a bmv700.


smartshunt-50mv.png (646.7 KiB)
shunt-example.png (327.4 KiB)
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redtoad avatar image redtoad commented ·
Thanks for your detailed response. I'm encouraged!

The caveat you closed with makes me wonder -- aren't those blocks on the ends of the shunt essentially solid brass? Is there a likelihood of destroying the shunt in trying to drill into the back side of it, opposite the "Smart" part? Would the risk be less, by drilling and tapping for very short screws?

Thanks again for any insight.

Mike


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klim8skeptic avatar image klim8skeptic ♦ redtoad commented ·
@RedToad Your only going to need to drill a 5-6mm deep hole for the screw holes, safe enough unless you slip and stab anything delicate.

First step will be to contact you dealer and see if there are any pcb's available.

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Paul B avatar image
Paul B answered ·

the shunt sizes are set by adjusting the setup settings in the bmv setup mode

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