Cordex® 24-400W 19” Integrated Shelf Installation and Operations Guide | 6 - Wiring and Connections
It is recommended, for each feed, to use 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.
Table 2.
Recommended AC Supply Configuration
AC Input (Vac)
Number of Recti-
fiers on AC Feed
Circuit Breaker, Ex-
act Value to Use (A)
90° C Wire Gauge
to use at 30° C
ambient (AWG)
120/240
1
10 or 15
14
120/240
2
20
12
120/240
3
20
12
An external surge protection device is not required. The rectifiers are protected by internal MOVs.
6.5. AC Input
CAUTION:
Route the AC input wires in flexible or rigid conduit as far away as possible from the DC
power wires to minimize EMI disturbances.
1. If the shelf is factory-equipped with a line cord, proceed to the next section.
2. Refer to the -08 customer connections drawings (rear view – back cover removed).
3. Remove the metal cover from the rear of the shelf to expose the wire-way for the input terminal
blocks.
4. Attach the conduit retainers to the wire-way hole(s) and route the AC cables through.
5. Secure the wires to the AC input and chassis ground terminals as required. Tighten the cable
connector to the AC cable (conduit similar).
6. Replace rear cover once all connections have been completed.
6.6. Calculating Output Wire Size Requirements
Wire size is calculated by first determining the appropriate maximum voltage drop requirement. Using the
formula below calculate the CMA wire size requirement. Determine the size and number of conductors
required to satisfy the CMA requirement.
CMA = (A x LF x K) / AVD, where:
•
CMA: Cross section of wire in circular MIL area
•
A: Ultimate drain in amps
•
LF: Conductor loop feet
•
K: 11.1 constant factor for commercial (TW type) copper wire
•
AVD: Allowable voltage drop
9400021-J0 Rev B
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