Vset To Equalize Battery Module Voltages - Generac Power Systems PWRcell Reference Manual

Vset to Equalize Battery Module Volt-
ages
Improper cell balance leads to lower power capacity of a
PWRcell system. When adding a new battery module to
an existing PWRcell system all of the module voltages
must be equalized.
70 %
70 %
30 %
Figure E-7. Improper cell balance leads to lower
power capacity of the system
70 %
70 %
Discharge
30 %
Figure E-8. Proper cell balance ensures maximum
power capabilities from system
Using Vset Function
NOTE: Perform Vset before installing new modules.
NOTE: To perform Vset, the existing battery modules
must be at higher voltages than the new modules. Vset
procedure works by discharging existing battery modules
to match new module voltage(s).
Ensure inverter system is set to Priority Backup or
1.
Clean Backup system mode.
Prior to installing, measure the voltage of each new
2.
battery module at the module main power termi-
nals using a digital multimeter and record the volt-
age values for each.
NOTE: If installing more than one module, where those
module's voltages differ by more than 300 mV (0.3 Volts)
from each other, perform the Vset procedure individually
for each module to ensure proper cell balancing.
Navigate to the PWRcell Battery device page and
3.
press the center button to access the main menu;
then select 'Mod. Settings.'
Navigate to the last setting, 'Module Vset', and
4.
select using the center button.
Diagnostic Repair Manual
100 %
Charge
100 %
60 %
011876
30 %
100 %
30 %
100 %
Charge
30 %
100 %
011877
Enter the voltage value measured from the new
5.
module(s) if different from the default value and
'Save' changes.
From the PWRcell Battery device page, press the
6.
center button.
Select 'Start Vset' from the PWRcell Battery main
7.
menu.
The battery will start discharging. Look for the Bat-
8.
tery Status LED to be green, rapid flashing.
NOTE: The system will automatically stop discharging
and disable the battery once the existing modules dis-
charge to the voltage set.
Once Vset has finished, check existing module
9.
voltages at their module main power terminals with
a digital multimeter to ensure they match the volt-
ages of the new module(s).
Add the new battery module(s) to the stack by con-
10.
necting the battery power harness and appropriate
CAT5 communication cables. See PWRcell Bat-
tery Installation and Owner's manual for more
information.
Maximizing Battery Capacity After Upgrade
To maximize battery capacity after adding new battery
modules, allow the battery to charge to 100%. Leave the
system set to Priority Backup or Clean Backup system
mode for several days to allow the battery cells to bal-
ance.
Appendix E Battery
137