Omron 3G8F7-CRM21, User Manual

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198
Wiring for Power Supply
Section E-5
Precautions for Correct Use
With the Slave Units of network power supply type, the external I/O devices
are also supplied power through the communications power supply connected
to the Master Board or a Repeater Unit, via Flat Cables.
Therefore, the output current of communications power supply must include
the consumption current and the actual load current of the external I/O
devices into calculation.
Below is a calculation example of the consumption current for a Bit Slave
Unit's communications power supply.
1) In case of an Input Slave unit:
Consumption current by the communications power supply
= Current consumed by a Bit Slave for communications
+ (Input current of a Bit Slave
×
the Number of used channels)
+ (Current consumed by a sensor
×
the Number of used sensors)
2) In case of an Output Slave unit:
Consumption current by the communications power supply
= Current consumed by a Bit Slave for communications
+ (Actual load current of an actuator
×
the Number of actuators)
3) In case of a Mixed Slave unit:
Consumption current by the communications power supply
= Current consumed by a Bit Slave for communications
+ (Input current of a Bit Slave
×
the Number of used channels)
+ (Current consumed by a sensor
×
the Number of used sensors)
+ (Actual load current of an actuator
×
the Number of actuators)
E-5-2 Wiring the Communications Power Supply
Use a round cable II, Flat Cable I or Flat Cable II, and connect the
communications power supply to the Master Board.
Communications connector
Communications power
supply connector
Communica-
tions power
supply,
24 VDC
+
BS
+
−
BS
−
3 m max.
BS
+
BS
−
To the 24-VDC
communications
power supply