Siemens simatic c7-621, Руководство по установке оборудования

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7-7
C7-621 / C7-621 AS-i Control Systems
C79000-G7076-C621-01
7.2 Connecting Loads/Actuators to the Analog Output
With the analog output, you can supply loads/actuators with current or
voltage.
You should use shielded, twisted pair cables for analog signals. This reduces
the effects of noise. The shield of the analog cables should be grounded at
both ends. If there are potential differences between the ends of the cable, an
equipotential current can flow through the shield and cause disturbances to
the analog signals. In this case you should only ground the cable at one end.
The abbreviations used in Figures 7-5 to 7-6 have the following meaning:
AO-I: Analog output current
AO-U: Analog output voltage
R
L
: Load/actuator
AO-M : Chassis connection (reference potential of the analog output)
L+: Power supply connection 24 V DC
M: Chassis connection of the C7
Figures 7-5 to 7-6 show how the loads/actuators must be connected to the
current or voltage outputs of the analog output module.
Overview
Cables for Analog
Signals
Abbreviations
C7-621 Analog I/Os