If you want to define the setting for a pump between the Pump On and Pump Off depths then an IF statement based on the Pump flow will work better as in this example, which changes the setting for the pump between a depth of 18 and 20 meters. The IF statement based on flow will ensure the rule only applies when the Pump Control depth is moving from the Pump On depth to the Pump Off depth and NOT between the Pump Off and Pump On depth. Figure 1 shows how the Pump Flow is related to the Pump Setting.
IF PUMP PUMP1 FLOW > 0.000000
AND NODE WELL HEAD > 18.000000
AND NODE WELL HEAD < 20.000000
THEN PUMP PUMP1 SETTING = 0.700000