Verifying The Ma Range; Volume; Readings; Vessel Shape And Dimensions - Siemens SITRANS L 7ML5400 Operating Instructions Manual

Note
If default values (4 and 20 mA) are used for the minimum and maximum mA limits, the mA
output (shown in Current Output Value (2.5.8.) (Page 183)) will remain at the set mA limit,
even if the level reading falls below/rises above the mA setpoints.
7.4.2

Verifying the mA range

Checks that the external device can track the entire 4 to 20 mA range sent by the SITRANS
LUT400. Follow the steps below if actual mA readings differ between the LUT400 (shown in
Current Output Value (2.5.8.) (Page 183)) and an external device (such as a PLC).
1. To test the loop current, set Current Output Function (2.5.2.) (Page 180) to Manual, then set
the value to use in Manual Value (2.5.7.) (Page 183).
2. Check that the external device displays the same mA reading as the mA value set above.
3. If external device reading differs from the set manual value on the LUT400, adjust the
reading on the external device to match the reading on the LUT400.
7.5

Volume

Volume is used in two situations:
1. Calculate and display volume instead of level.
2. Calculate pumped volume to accomplish the following:
• Totalize the volume of material that is pumped out of the wet well.
7.5.1

Readings

When using volume, readings are given in units specified in Volume Units (2.6.2.) (Page 186).
7.5.2

Vessel Shape and Dimensions

There are many common vessel shapes to select from. (See Vessel Shape (2.6.1.) (Page 184).
If possible, use one of these.) Each vessel shape uses the Low Calibration Point (2.2.1.)
(Page 176) in its calculations of volume.
Some vessel shapes also require extra dimensions to calculate the volume. Do not estimate
these values. They must be correct to ensure the accuracy of your volume calculations.
SITRANS LUT400
Operating Instructions, 04/2021, A5E33329501-AG
General Operation
7.5 Volume
95