Mitsubishi Electric QJ71LP21 Reference Manual page 61

3 SPECIFICATIONS
Power supply A
NF
Power supply A
NF
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(8) Configuration of redundant power supply on a remote I/O station
A redundant power supply can be configured on a remote I/O station by
mounting a pair of power supply modules onto the dedicated base unit.
A redundant power supply offers the following advantages.
1) The remote I/O station can continue the operation after either power
supply module stops power supply
The remote I/O station with a redundant power supply can continue
the operation even if either of the power supply modules stops power
supply, as the remaining power supply module supplies power instead.
2) A faulty power supply module can be replaced online (hot-swapping)
A faulty power supply module can be replaced online (hot-swapping),
as the remote I/O station operates using the remaining power supply
module.
To take advantages of the redundant power supply, connect separate
power supplies to the power supply modules.
QCPU QJ71
Q61P
LP21
Q38RB
Q64RP
Q64RP QJ72
LP25
Power supply B
NF
QCPU QJ71
Q61P
LP21
Q38RB
Q64RP
Q64RP
QJ72
LP25
Power supply B
NF
If either of the power supply modules stops supplying power, the remote I/O
station detects error code 1510 "SINGLE PS DOWN" or 1520 "SINGLE PS
ERROR" (moderate error). Errors in the remote I/O station can be
confirmed through the PLC diagnostics/system monitor of GX Developer
(version 8.17T or later), the ERR. LED of the remote I/O module, and the
ERR contact of the power supply module.
I/O I/O
I/O I/O
Power supply A stops supplying power
QJ72LP25 continues operation by supplying
power from power supply B
I/O I/O I/O I/O
MELSEC-Q
I/O I/O I/O
I/O
I/O I/O I/O I/O
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