Watson-Marlow 720UN and 720SN User Manual
40
16.4 Outputs
The pump offers four relay status outputs. See 12
Switching the pump on for the first
time
for initial start-up defaults. Each of six parameters can be configured to any out-
put, or more than one output.
The parameters are:
Run/stop
Provides a status output to indicate whether the pumphead is in a running or
stopped condition. When running at 0 rpm, the run/stop output indicates run-
ning.
Direction
Provides a status output to indicate which direction the pump is set to run in.
Auto / man
Provides a status output to indicate whether the pump is in analogue control
mode or manual control mode.
General alarm
Provides an alarm output when any system error condition occurs except: leak
detected; analogue signal out of range; analogue over-signal; analogue no sig-
nal.
Leak detected
When used with a leak detector, this output provides an alarm when the pump
has been automatically switched off following tube failure.
Head
Provides an alarm when the pumphead track is open. If it is running, the pump
will stop.
Outputs 1-4 are available as single-pole change-over relay contacts: Relay 1, 2, 3 and
4. Connect to the normally open or normally closed contacts of the relay as required
and configure the pump’s software accordingly. See below in this section.
Note
: The maximum rating on the relay contacts of this pump is 30VDC; maximum
load 30W.
