Watson & Sons 520DUN user manual 22.14 RS485 input, DC Voltage Max load Typical use

DC Voltage	Max load	Typical use
		Voltage supply for inputs using remote
+5V	10mA	switch.
		Possible voltage supply for outputs if only 5V
		is required.
		Possible voltage supply for inputs using
		remote switch.
		Possible voltage supply for outputs. Voltage
+12V	10mA	supply for Watson-Marlow Tube Monitor leak
		detector.
		Part voltage supply (-12V also needed) for
		the Watson-Marlow proximity switch.
-12V	10mA	Part voltage supply (+12V also needed) for
		the Watson-Marlow proximity switch.

+10V

Reference voltage for remote potentiometer speed control. Do not use as a general supply

(from J7)

voltage.

Note: All DC supplies are stabilised.

22.14 RS485 input

Connect your network link to J10 using a screened twisted pair: A to A, B to B, screen to 0V. Ensure that the pump is configured to operate under Network control. More than one pump may be controlled with the same RS485 signal: connect all pumps in parallel. See 24 Network control and operation.

The shorting link at J20 must be cor- rectly positioned to allow RS485 control to function properly. Fit the shorting link of a single pump or of the last pump on a network line in the position marked INT on the three-pin header; fit the shorting link of all other pumps on the network line in the position marked EXT on the three-pin header.

Watson-Marlow 520DuN IP66/NEMA 4X User Manual 70