When Two Or More Inverters Are Connected - Mitsubishi Electric FR-A7NC Instruction Manual

HOW TO CHECK FOR ERROR USING THE LEDS

9.2 When two or more inverters are connected

The following system configuration shows how the cause of a fault can be checked with the LED status of
the inverter communication option (FR-A7NC) and countermeasures for the fault.
(In this example, assume SW, M/S, and PRM LEDs of the master module are OFF (master module is in
normal operation).)
Power
supply
LED Status
Inverters (FR-A7NC)
Master
Unit
Station 1 Station 2 Station 3
RUN
RUN
L.RUN L.RUN
SD SD
TIME
RD RD
LINE
L.ERR L.ERR
or
RUN RUN
TIME
L.RUN L.RUN
LINE
SD SD
RD RD
L.ERR L.ERR
98
CPU Master
module
Station 1
Inverter A
FR-A7NC
RUN
L.RUN
SD Normal
RD
L.ERR
RUN
L.RUN
Poor contact of the FR-A7NC with the
SD
inverter
RD
L.ERR
Station 2
Inverter B
FR-A7NC
Cause
: On, : Off, : Flicker, *: Any of on, flicker or off
Station 3
Inverter C
FR-A7NC
Corrective Action
⎯
Plug the FR-A7NC securely.
Check the connector.