diyreg
New Member
I recently purchased an MPP PIP 3048 LV-MK. I am testing it with a continuous load that currently exceeds solar output most of the time.
The inverter appears to be charging the battery from solar in SbU + SLb/UdC mode when the battery voltage drops to the "back to utility" voltage (program 12), even though the solar output is less than the load.
When the battery voltage drops to 49V, I was expecting the AC to supplement the load as it does in SUb mode and leave the battery at 49V until/if solar exceeds the load. However, that is not what happens.
Watchpower shows:
* solar->battery with 10A charging current
* AC->load
* I have a separate power meter on the AC in and out and I see the full load power from AC in. All solar output is charging the battery.
It seems wasteful to charge the battery instead of applying maximum solar output to the load. Excess solar later in the day could charge the battery without wasting AC power. This charging may also lower battery life due to extra cycling with varying solar output.
Is this the expected behavior, despite "SLb", or is there something wrong with the settings or the inverter?
settings:
The inverter is on current firmware: 61.02
Thanks much!
The inverter appears to be charging the battery from solar in SbU + SLb/UdC mode when the battery voltage drops to the "back to utility" voltage (program 12), even though the solar output is less than the load.
When the battery voltage drops to 49V, I was expecting the AC to supplement the load as it does in SUb mode and leave the battery at 49V until/if solar exceeds the load. However, that is not what happens.
Watchpower shows:
* solar->battery with 10A charging current
* AC->load
* I have a separate power meter on the AC in and out and I see the full load power from AC in. All solar output is charging the battery.
It seems wasteful to charge the battery instead of applying maximum solar output to the load. Excess solar later in the day could charge the battery without wasting AC power. This charging may also lower battery life due to extra cycling with varying solar output.
Is this the expected behavior, despite "SLb", or is there something wrong with the settings or the inverter?
settings:
1 | output source (load source priority) | SbU |
2 | max charge | 20 |
5 | batt type | |
11 | max util charge | 2 |
12 | switch battery to AC | 49 |
13 | switch AC to battery | 50 |
16 | charge source (solar dest priority) | SLb/UdC |
23 | bypass | enable |
25 | fault code | enable |
26 | charge | 56.8 |
27 | float | 53.1 |
29 | low cut off | 48 |
The inverter is on current firmware: 61.02
Thanks much!
