Partial Home Backup - Generac Power Systems PWRcelP XVT076A03 Installation And Owner's Manual

Electrical Connections

Partial Home Backup

CAUTION
Equipment damage. Never connect protected loads
terminals to other sources of power, including any other
inverter, the utility grid, or a generator. Doing so could
result in equipment or property damage.
CAUTION
Equipment damage. Never connect protected loads
output from inverters in parallel. Doing so could result
in equipment or property damage.
See Figure 5-8. When configured to operate with a
PWRcell ATS installed between a main panel and
subpanel, a PWRcell system can provide backup power
to the subpanel, referred to below as a protected loads
subpanel, during a utility service interruption.
When a service interruption occurs, relays inside the
inverter isolate the inverter's AC grid connection, the
transfer switch transfers to the inverter as a power
source, and the inverter powers protected loads, using
PV and battery power. The ATS transfer typically takes a
fraction of a second but may take up to a few seconds
depending on how the grid service is interrupted.
In this configuration, the PWRcell Inverter will control the
PWRcell ATS upon loss of utility voltage.
NOTE: This configuration is not suitable for three-phase
installations. This includes panels powered by feeders
carrying 2 of the 3 phases.
A PWRcell system configured to operate with a PWRcell
ATS can accommodate up to 9 kW – 11 kW maximum
continuous load. This requires at least 6 – 8 battery
modules, respectively, to be installed in one – two
PWRcell Battery cabinets. Please reference pertinent
product specifications for desired configuration.
NOTE: A qualified installer must ensure proper load
sizing of the protected loads panel so as to not overload
the PWRcell system as an optional standby power
source in any partial home backup installation.
NOTE: Actual power output for protected loads during a
grid outage will depend on system sizing for batteries and
solar array.
General Wiring Guidance:
1. See
Figure 5-8. Install a suitably rated, listed over-
current protection device (OCPD) at the main
panel.
2. Land new feeder conductors from the new OCPD
at the main panel at the 'N' terminals of the
PWRcell ATS.
20
3. Land new feeder conductors from the 'T' of the
ATS to the Line side of the protected loads
subpanel.
4. Land the PWRcell Inverter protected loads wiring
(L1 Protcd / L2 Protcd) to the 'E' terminals of the
ATS.
5. Land the inverter protected loads neutral wire (N2
(000648a)
Protcd) to the neutral bar in the ATS.
6. Land an equipment grounding conductor from the
PWRcell Inverter to the ATS ground bar.
7. Install a 2-Pole 40 A OCPD for interconnection of
the PWRcell Inverter at the protected loads
subpanel.
(000649a)
8. Land the inverter AC Grid Connection wiring (L1 /
L2) to the OCPD for interconnection.
NOTE: Improper installation of a PWRcell ATS can result
in an objectionable current path through a paralleled neu-
tral connection. Reference NEC 250.6. The neutral con-
ductor for the inverter AC Grid Connection circuit is not
required to be installed to the point of interconnection
with the utility as permitted by the exception in NEC
200.3. Follow the PWRcell ATS Installation Manual for
proper installation. The installer is responsible for compli-
ance with applicable national, state, and local codes.
9. Install CTs in the AC Main Panel using the CTs
adapter and run Cat 5 or Cat 6 from the CTs
adapter to one of the inverter CTs ports.
10. Run Cat 5 or Cat 6 from the PWRcell ATS
Controller to the PWRcell Inverter for ATS controls.
11. Size protected loads subpanel loads to whichever
is the lesser of...
a) The rating of the main panel circuit breaker
installed Step 1 that connects to the PWRcell ATS.
b) the backup power rating of the attached PWRcell
Battery(ies).
NOTE: Class 2 low voltage cable shall be installed inde-
pendent of other power conductors. See NEC 725.136
for additional information.
The following is not supported with Partial
Home Backup at this time:
– Parallel backup power with another PWRcell
system.
– Parallel operation with other energy/battery stor-
age solutions.
– Installations with other manufacturers' transfer
switches.
– Installations without a compatible Generac trans-
fer switch.
– Support for 3 phase 120/208 V inverter installa-
tions.
Installation and Owner's Manual for Generac PWRCell Inverter