Watson-Marlow Qdos30 Universal - Manual (Page 37)

Watson-Marlow qdos30 Universal and Universal+ Pump User Manual 37
• The pump is now calibrated.
15.5 Analog 4-20mA mode
In this remote operating mode the flowrate will be proportional to the external
milliamp signal input received by the pump. The Universal pump will operate at
0 rpm when 4.1mA is received and 125 rpm when 19.8mA is received.
In the Universal+ pump the relationship between the external milliamp signal and
the flowrate is determined by configuring the two points A and B as shown in the
graph below. The rate of flow can be proportional or inversely proportional to the
analogue milliamp input.
The default values stored in the pump are A (4.1mA, 0 rpm) and B (19.8mA, 125 rpm).
B
mA
Flowrate
A
When the mA signal received is greater than the level defined by point A, the run
status output will be energised as the pump is running.
To select Analog 4-20mA mode:
• Select MODE.
• Using the +/- keys scroll to Analog 4-20mA and press SELECT.
The current signal being received by the pump is displayed, for information only, on
the HOME screen.