39
9400016-J0 Rev E
CXPS-E3
User Guide
7.3 AC wiring
To ease future access issues, connect the AC circuits to all rectifier shelves at the time of initial installation.
7.3.1 AC feeder protection and sizing
To maximize system reliability, each feed should have a dedicated protection feeder breaker located at the AC
distribution panel. The feeder breaker can also act as the disconnect device for the connected modules.
7.3.2
AC wiring for 2.4kW | 3.0kW rectifier shelf
The 2.4kW | 3.0kW rectifier shelves used within the CXPS-E3 systems are 19- or 23-inches in width. The
individual rectifier shelves are wired to the customer provided AC termination panel. The AC input is routed
through a 3/4" trade size knockout on the side of the shelf for a direct connection. The AC wiring size can vary
based on local electrical codes.
The recommended AC breaker and wire gauge sizes are as follows:
Rectifier shelf
Recommended AC breaker size
Recommended AC wire size (AWG)
Single phase , 208Vac – 277Vac
23" breaker = 2× 40A & 1× 20A AC breakers
19" breakers = 4× 20A AC breakers
#8 AWG for 40A breaker
#12 AWG for 20A breaker
Refer to the Specifications in Section 3 for further details.
1. Ensure that all modules are removed from the shelf.
2. At the back of the shelf, remove screw and flip the cover down (two places) to access the AC input terminal
blocks: each terminal pair corresponds to either two rectifiers or a single rectifier as shown in Figure 20.
3. The wire way is designed for two customer-supplied, 3/4" conduit fittings for the AC supplies located one on
each side of the shelf. Attach the conduit retainers to the wire way holes and route the AC cables through
them.
4. Secure the wires to the AC input and AC ground terminals. Refer to the customer connection drawing at the
end of the manual.
5. Tighten the cable connector to the AC cable (conduit similar).
6. Replace back covers once all connections have been completed.
NOTE
Verify NO rectifiers are installed in the rectifier shelves at this time.
CAUTION!
To minimize EMI disturbances, route the AC input wires in flexible or rigid
conduit and located as far away as possible from the DC power wires.
WARNING!
Use care when removing or replacing the covers for the AC input connections. Never assume
that an electrical connection or conductor is not energized.
Figure 20 — AC input and ground for 23inch shelf
Single feed for rectifier
slots #1 and #2
Bottom connector: single feed
for rectifier slots #3 and #4
Top connector:
single feed for
rectifier slot #5
AC Ground
AC Ground
Cover
flipped
down
NOTE:
Rectifier slots are numbered 1 to 5 from the left front of the shelf.
