Nortel Meridian 1 Hardware Replacement Manual page 234

Page 234 of 250
553-3001-520 Standard 17.00 January 2002
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 43 on page 240, 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).
DANGER
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.
3 Remove the grill on the rear of the pedestal.