Siemens SIMATIC FM 453, Manual

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4-18
FM 453 Servo Drive / Step Drive Positioning Module
C79000-G7076-C453-01
The 5 V or 24 V power supply to the encoders is generated within the module
and is available on the female sub-D connector, and so you can power the
encoders by way of the connecting cable, without additional wiring. The
available voltage is electronically protected against shorting and thermal
overload, and is monitored.
Table 4-8 Electrical Parameters of Encoder Power Supply
Parameters Min Max Unit
5 V power supply
Voltage 5.1 5.3 V
Ripple 50 mV
ss
Current carrying capacity per channel 0.3 Q
24 V power supply
Voltage 20.4 28.8 V
Ripple 3.6 V
ss
Current carrying capacity per channel 0.3 Q
The maximum cable length depends on the specifications of the encoder
power supply, and on the transfer frequency. For trouble-free operation, you
should not exceed the following values when using SIEMENS cable sets:
Table 4-9 Cable Length as a Function of Encoder Power Supply
Supply Voltage
Tolerance
Power
Consumption
Max. Cable
Length
5 V DC 4.75 V to 5.25 V < 300 mA 25 m (82 ft)
5 V DC 4.75 V to 5.25 V < 210 mA 35 m (115 ft)
24 V DC 20.4 V to 28.8 V < 300 mA 100 m (328 ft)
24 V DC 11 V to 30 V < 300 mA 300 m
Note
If you want to use incremental encoders with cable lengths longer than 25 or
35 m (82 or 115 ft), select a type that uses a 24 V power supply.
Table 4-10 Cable Length as a Function of Transfer Frequency
Encoder Type Frequency Max. Cable Length
Incremental encoder
1 MHz 10 m (32.8 ft)
Incremental encoder
500 kHz 35 m (115 ft)
Absolute encoder (SSI)
1.25 Mbps 10 m (32.8 ft)
Absolute encoder (SSI)
156 kbps 250 m
Encoder Power
Supply
Connecting Cables
to Encoder
Wiring the FM 453