I have a working installation of a BlueSolar 150|35, v1.16, connected to 2 parallel series of 3 250W/24V panels. The battery bank consists of 5 pairs of 2 batteries, each battery a 110VA 12V stationary battery. The system has been working for almost 2 years without any problem. Four days ago, this changed:
- the system did not have power anymore to run a water pump
- because the battery voltage was too low, about 22.5 Volts
- the MPPT was stuck in 'float' mode really early in the day and because of this, never charged to batteries
Yesterday I managed to (re)connect the MPPT to a Linux machine using the VeDirect RS232 connector. Connecting using minicom, baudrate 19200 and 8bits, I got data frames from the MPPT, below a copy of one of them:
PID 0xA04B
FW 116
SER# HQ1746JGWU1
V 27320
I 300
VPV 101460
PPV 9
CS 5
ERR 0
H19 159940
H20 36
H21 723
H22 23
H23 400
HSDS 314
This tells me, that the MPPT thinks that the battery voltage is 27320 volts. One minute after seeing this, I measured the battery voltage using a multimeter. Battery voltage is 23,3 volts on the multimeter. The MPPT software seems to stay in float, because of the high voltage it measures.
What are my options ?
- is there a way to re-calibrate the voltage measurement of the batteries ?
- is it safe to re-configure the treshold voltage, set it to a higher value, like 30 or 32V, in the hope that it will go to float when the battery actually has 27 or 28 Volts ?