User`s manual
Overview Power supply modules
MELSEC System Q, Hardware 7 – 1
7 Power supply modules
7.1 Overview
Observe the input voltage, output current and the power consumption of the mounted modules
when selecting the power supply.
For information about power consumption of the different modules refer to chapter 3 and chapter
12.
Redundant power supply
To continue the operation of a PLC system or remote I/O station, when a power supply failure
occurs, two of each power supply Q63RP or Q64RP can be mounted on a base unit Q38RB,
Q68RB or Q65WRB.
During normal operation (no power supply failure) the base unit is supplied by both power sup-
plies. If a failure of one power supply occurs, the other power supply takes over the total supply
of the base unit. The LED of the failed power supply changes its colour from green to red.
Replacement of the module is possible, during system operation.
In case of a failure the total supply is done by one power supply. Therefore the current of the base
unit and of the mounted modules must not exceed 8.5 A.
When connecting the uninterruptive power supply (UPS)
In case of connecting the power supplies to an UPS (uninterruptable power supply), the input
voltage of the power supplies may go maximum 5 % below the rated voltage.
Notes on handling
E
CAUTION:
● Note the different input voltages of the power supplies.
● Do not drop the devices or subject them to heavy impact.
● Do not remove the printed-circuit board of the device from its case.
● When drilling screw holes or wiring, cutting chips or wire chips should not enter
ventilation slits.
● Tighten the fixing screws using torque within the ranges of the table 7-1.
Screw Tightening torque range (Ncm)
Terminal screw (M3.5x7) 66 to 89
Module fixing screw (M3x12) 36 to 48
Tab. 7-1: Tightening torque range