EVCO EVB1256N9 User Manual
Page 21
EVCO S.p.A.
EVBOX1 | Installation guide ver. 1.2 | Code 144BOX1E124
page 21 of 88
4.7
Insertion of the RS-485 MODBUS port termination resistor
To reduce reflections on the signal transmitted through the cables connecting the devices to a RS-485 network it is necessary to insert
the termination resistor of the first and last elements of the network.
To insert the termination resistor place the jumper as shown in the following drawing.
4.8
Connection of the RS-485 network cable screen to GND
To prevent external disturbances from being interpreted as signals by the RS-485 network, it might be necessary to connect the cable
screen of the RS-485 network to GND
To connect the cable screen to GND, place the jumper as shown in the following drawing.
4.9
Warnings for the electric connection
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do not use electric or pneumatic screwdrivers on the device terminal board
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if the device has been taken from a cold to hot place, humidity could condense inside; wait about 1 hour before powering it
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make sure that the power supply voltage, the frequency and the operational electric power of the device, correspond with
those of the local power supply; see chapter “TECHNICAL DATA”
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disconnect the device power supply before proceeding with any type of maintenance
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connect the device to a RS-485 MODBUS network using a twisted pair
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position the power cables as far away as possible from the signal cables
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for repairs and information regarding the device, contact the EVCO sales network.