Generac Power Systems PWRcell Reference Manual page 20

Section 4 PWRcell Inverter
Multiple Inverter Systems Cross-Talking
•
Refer to
Commissioning Multiple Inverter Sys-
in
tems Appendix B Inverter
missioning procedures were followed.
•
If suspected that systems on-site are cross-com-
municating, refer to
in
Procedure Appendix B
Inverter Error
If the Inverter goes to an error state, the inverter light will
be red and the home screen will display, 'error detected
on PWRcell [model]'. Navigate to the inverter device
page to view specific inverter state. Certain error states
will show specificity (e.g. error: REbus fault). Others will
show a generic error.
1. Check Inverter Settings
a. Ensure the inverter is set properly for the
configuration of the site.
b. Improper configuration of settings can lead to
an inverter error.
2. Disable/Enable
a. For generic errors, attempt to disable the
inverter then re-enable. This could clear a non-
terminal/ non-persistent error.
b. Briefly observe inverter operation. If the
inverter returns to error state proceed with
Steps 3 and 4.
3. Check REbus Fuses
a. If after attempting steps one and two the
inverter error persists, perform a shutdown of
the system by pressing and holding the red
shutdown button.
b. Use a DMM to ensure there is no voltage
present at the DC terminals.
c. Locate the REbus DC fuses at the lower left
corner of the power core (two round black fuse
holders). Reference the inverter wiring
compartment cover diagram if necessary.
d. Unscrew REbus fuses by hand.
e. Use a DMM to test both fuses for continuity.
The meter should ring out with an audible tone
if the fuses have not been blown.
f. If one or more fuses has been blown, this
indicates a short on REbus either from an
issue with the wiring or with one of the
connected devices.
g. Follow steps 4 and 5.
4. Basic Function Test
a. With the system shutdown, turn off all four
REbus DC disconnects to isolate the Power
Core from any possible shorts on the DC side.
16
to verify proper com-
PLM Cross-talk Recovery
Inverter.
b. Recover from Shutdown Mode using the
center button.
c. Navigate to the inverter device page and
enable the inverter.
d. Verify inverter connects to the grid and
displays 'grid connected'.
e. Verify the inverter is able to bring up REbus
voltage at the home screen. DC voltage should
be at least 360 VDC.
f. Verify the Inverter light is green.
g. If the inverter goes immediately back into error
or REbus DC voltage does not reach a
minimum of 360 VDC, call Generac PWRcell
Technical Support. Otherwise, proceed to the
next steps.
5. REbus DC Wiring
a. If Power Core passes the Basic Function Test,
proceed to isolate the REbus short.
b. Ensure REbus wiring is not loose at any of the
terminals.
c. Visually inspect wiring for defects to best
ability.
d. With the DC disconnects turned off, use a
DMM to check each DC circuit for continuity
between positive and negative, positive and
ground, negative and ground at the inverter.
e. Set the DMM to measure ohms in the MΩ
range.
f. Measure the resistance at each DC circuit and
record the measurements. Measure positive to
negative, positive to ground, negative to
ground. Resistance should be greater than 10
kΩ.
g. If a set of REbus wires rings out with continuity
across conductors, positive to ground,
negative to ground, or measures 10 kΩ or less,
there is a short on that wiring.
6. Check AC Wiring
a. Visually inspect for miswiring or arcing.
b. Perform voltage checks with a DMM.
7. Devices
a. If fuses are intact and wiring has been verified,
a short could be registering on REbus due to a
failed PV Link or Battery on the system.
b. Attempt to isolate the circuit with the short by
enabling the inverter with only one DC
disconnect on at a time. Repeat this for each
DC circuit. Always disable the inverter before
turning any DC disconnect to the ON position.
c. After isolating the circuit, inspect the devices
connected to that circuit.
Diagnostic Repair Manual