Saving Energy - Siemens SITRANS L 7ML5400 Operating Instructions Manual

General Operation
7.7 Pump Control
Example:
A range of 0.5 meters is used to vary the setpoint. The randomly-selected setpoints are
always inside the ON and OFF setpoints.
①
②
③
④
7.7.6.5

Saving energy

Pumps can use different setpoints at different times of the day to account for variable energy
costs.
The following example illustrates high energy cost usage reduction and/or elimination by
using the SITRANS LUT400 Energy Savings function on a wet well (pump down application)
using pump 1.
Pre-requisite: enable Energy Savings function (set Enable (2.7.2.2.1.) (Page 193) = Enabled)
116
Random setpoint range
ON setpoint
Level setpoint variation
OFF setpoint
Normal Operation
Uses the standard ON and OFF setpoints (ON
Setpoint Pump 1 (2.7.1.6.) (Page 190)/ OFF Set-
point Pump 1 (2.7.1.7.) (Page 190)). Energy cost
is at minimum.
Peak Lead Time (2.7.2.2.2.) (Page 193) = 60
minutes.
Pumps down the wet well regardless of the pump
ON Setpoints. This ensures that the wet well
starts the high cost period at the OFF Setpoint
Pump 1 (2.7.1.7.) (Page 190). Energy cost is at
minimum.
Peak 1 Start Time (2.7.2.2.3.) (Page 193) = 17:30.
Starts using the energy savings setpoints (Peak
ON Setpoint Pump 1 (2.7.2.2.13.) (Page 196) and
Peak OFF Setpoint Pump 1 (2.7.2.2.14.)
(Page 196)).
Energy cost is at maximum.
Operating Instructions, 04/2021, A5E33329501-AG
SITRANS LUT400