vas
Well-Known Member
hello all,
just had a go running the watermaker through the inverter.
wasn't exceptionally sunny when I tried it (panels could only bring around 12-13A@24V)
Victron BMV-700 reported a consistent draw of 84-85A from the batteries. I guess that means just under 100A total as panels were surely pumping their 12-13A at the same time and Victron reports the total IO value - of course both MPPT and Multiplus inverter/charger negatives go through the BMV700 shunt, so all's measured.
Voltage was down to 23.8V whilst doing that.
Kept it going for 20mins and checked throughout the time with my IR thermometer cables, batteries and connectors. Started at a 22C, ended 20m later at 27C max on the + terminal of the first Trojan and the terminal on the multiplus. The - terminal of the last Trojan one was 25C or something like that.
Cables according to specs must be 50mm^2, I've used 70mm^2 throughout (that's what I had tbh) lengths from Inverter to terminals is 1.5m + and 2m for the -
All cables have brand new terminals properly crimped on the shop (wasn't fun dragging all these around the city on foot...)
As soon as I stopped it, I measured 25.5V and 13A charging again. MPPT turned into float a few hours later.
Will do some more testing tomorrow and try to remember to turn off the victron mppt before running the tests and turn it back on in the middle to note the change in Amps.
Overall, it seems that if we do believe the BMV700 (which has been always accurate on DRAW, not SOC which is usually 100%...) then July and August lunch time I'm pretty sure I can run it for 30-40mins at a time.
Thoughts on the above welcomed!
cheers
V.
just had a go running the watermaker through the inverter.
wasn't exceptionally sunny when I tried it (panels could only bring around 12-13A@24V)
Victron BMV-700 reported a consistent draw of 84-85A from the batteries. I guess that means just under 100A total as panels were surely pumping their 12-13A at the same time and Victron reports the total IO value - of course both MPPT and Multiplus inverter/charger negatives go through the BMV700 shunt, so all's measured.
Voltage was down to 23.8V whilst doing that.
Kept it going for 20mins and checked throughout the time with my IR thermometer cables, batteries and connectors. Started at a 22C, ended 20m later at 27C max on the + terminal of the first Trojan and the terminal on the multiplus. The - terminal of the last Trojan one was 25C or something like that.
Cables according to specs must be 50mm^2, I've used 70mm^2 throughout (that's what I had tbh) lengths from Inverter to terminals is 1.5m + and 2m for the -
All cables have brand new terminals properly crimped on the shop (wasn't fun dragging all these around the city on foot...)
As soon as I stopped it, I measured 25.5V and 13A charging again. MPPT turned into float a few hours later.
Will do some more testing tomorrow and try to remember to turn off the victron mppt before running the tests and turn it back on in the middle to note the change in Amps.
Overall, it seems that if we do believe the BMV700 (which has been always accurate on DRAW, not SOC which is usually 100%...) then July and August lunch time I'm pretty sure I can run it for 30-40mins at a time.
Thoughts on the above welcomed!
cheers
V.
