Nortel Meridian 1 Replacement Manual page 342

Page 342 of 362
553-3001-520 Standard 16.00 April 2000
Replacing an NT7D10 PDU with an NT7D67CB PDU
Removing equipment
1 Check the length of existing wire to the PDU. Due to the location of the
field wiring terminal block on the NT7D67CB PDU, 6 to 9 inches more
length is required to reach its terminals than is required to reach those on
the NT7D10 PDU.
Note 1: The existing service loop where wire enters the pedestal may
have enough excess length or enough slack wire may exist in the conduit
path from the power plant to allow pulling a sufficient amount through
to the pedestal. Figure 41, located further on in this procedure, shows the
location on the NT7D67CB PDU to which wiring must extend. If
existing wiring will not reach, replace the entire wire run from the power
plant. Do not splice short pieces of wire onto the end of existing wiring.
Note 2: If a QCAD321 or an NT6D53 junction box is installed on the
power feed to the console, the wiring from the power plant may have to
be altered as follows:
• If five #4 AWG wires are run from the power plant to the junction box
(two BAT, two RTN, and one LRTN), then the junction box must not be
used. The junction box must be removed and the entire wire run from the
power plant to the pedestal must be replaced. Do not splice short pieces
of wire onto the end of existing wiring.
• If nine #4 AWG wires are run from the power plant to the junction box
(four BAT, four RTN, and one LRTN), then the junction box can be
used. However, the #10 AWG wires from the junction box to the pedestal
may have to be replaced to provide sufficient length. Do not splice short
pieces of wire onto the end of existing wiring.
2 Disconnect DC power at the source (not at the PDU).
Before performing these procedures, disconnect the power at the
source; simply turning off the circuit breakers does not shut off power
to the system monitor.
CAUTION