United Process Controls PROTHERM 50, Руководство по эксплуатации

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UNITED PROCESS CONTROLS GMBH Page 26 Protherm 50 P68.230
Option RS485 interface with MODBUS- driver
Installation and connector pin assignment
For the cable the usage of in twisted pairs with shield is recommended. which are expressly allowed for
RS485-wiring. In strongly disturbed surroundings, double shielded cables should be used.
unshielded cables cannot be used.
2-wire-operation
Only the pins 3 and 8 are used.
Cables with single shield, for example Belden 9841
4-wire-drove
the receive direction uses the pins 3 and 8, the transmit direction the pins 1 and 2.
Cables with single shield, for example Belden 9842
Bus-termination
At the end of the cable a resistance of 121R has to be connected between TX+ and TX - as well as
RX/TX+ and RX/TX -.
RS485 female connector
The shield has to be connected with the plug-case.
With double shielded cables, the outer shield has to be connected with the plug-casing and the
inner shield with GRD (pin 5).
Mounting-dimensions
Front panel cutout: 92x92mm
Depth behind front-panel 135mm without plugs