I have been have house bank voltage issues off of shore power. Last night test was no shore power and the solar was turned off. Zero issues
10awg is much to thin, it may be rated for 30A but it has too high a voltage drop. This is why you are having voltage issues. Use Google to find a voltage drop calculator or download the Victron Toolkit. 16A, 15ft, 10awg = 0.6V loss, 30A will be 1.2V loss. You need 6awg for low voltage drop at max 30A load.
When you have rewired your system, then if the SmartShunt and MPPT are connected to the Cerbo by VE Direct enable DVCC then SVS and SCS and the voltage loss will be compensated for. Details in the manual.
Thanks!
Pwfarnell,
Upgraded the wire from the MPPT to the house batteries yesterday. Last night’s voltage data looked normal. Yay!
One question though, as the solar energy ramps up this morning, the current to the batteries isn’t showing positive at the SmartShunt. Should it?
Depends what load you have on the system and if the mppt production is larger. Tjhe screenshot you showed above had 15.9A from the mppt and the battery was discharging at 6.6A (negative) so you had a 22.5A load at the time.
My interpretation is that the SmartShunt is showing the house loads at 9.18amp and the solar current is 13.9amp. ??
Attached is summary page and trend from SmartShunt.
MPPT is connected to same battery posts as the inverter/charger was does show positive when on shore power.
Thoughts?
Griff
Nothing attached.
It all depends on if the shunt is wired correctly then, only the shunt negative should be connected to the battery, which was my assumption.
From the manual Section 5.2
Current
This is the actual current flowing in or out of the battery. A negative current indicates that current is taken from the battery. This is the current needed for DC loads. A positive current means that current is going into the battery. This is current coming from charge sources. Keep in mind that the battery monitor will always indicate the total battery current, being the current traveling into the battery minus the current traveling out of the battery.
Assuming the shunt is wired correctly your reading is the solar is supplying 13.9A, the battery is supplying / discharging 9.2A so the load is 23.1A. However, whilst the shunt is showing discharge, the battery is actually charging so there is something wrong with the shunt wiring. Your mppt negative connection to the battery should go to the system side of the shunt, not the battery. So should the inverter negative and all other negatives.
Agree with all that.
I’ll take and send some pics of my setup. Worried I don’t have something right.
Thanks!
