IDEC FC4A-C10R2 User Manual page 447

Power Supply
• When turning off the power to the CPU module, also turn off the AS-Interface power supply. If the
Caution
CPU module is powered down and up while the AS-Interface power remains on, AS-Interface com-
munication may stop due to a configuration error, resulting in a communication error.
• Turn on the AS-Interface power supply no later than the CPU module power supply, except when
slave address 0 exists on the network. The two power supplies may be turned off in any order.
• Immediately after power-up, the CPU module cannot access slave I/O data in the AS-Interface mas-
ter module. Make the user program so that slave I/O data are accessed after special internal relay
M1945 (Normal_Operation_Active) has turned on. See page 28-24.
Power Supply Wiring Diagram
A recommended power supply wiring diagram is shown below. Use a common power switch for both the CPU module
power supply and AS-Interface power supply to make sure that both power supplies are turned on and off at the same time.
AC Power
Power Switch
CPU Module Power Supply
AS-Interface Power Switch (Note)
AS-Interface Power Supply
VLSV (very low safety voltage)
Note: A failed slave can be replaced with a new slave with address 0 without turning off the power to the CPU module and
the AS-Interface line. But, if power has been turned off before replacing the slaves, install a new slave with address 0 and
take one of the following steps, because the AS-Interface master module has to be initialized to enable communication.
•
Disconnect the AS-Interface cable connector and turn on both power supplies. Five seconds later, connect the AS-Interface
cable connector.
•
Turn on the CPU module power supply first. Five seconds later, turn on the AS-Interface power supply.
Slim Type CPU Module
FC4A-D40K3
24V DC
30V DC
« FC4A M
ICRO
28: AS-I
NTERFACE
AS-Interface Master Module
FC4A-AS62M
AS-Interface Cable Connector
S U ' M »
MART SER S ANUAL
M C
ASTER OMMUNICATION
Slave 2
Slave 1
28-7