Emerson Rosemount 2151N Reference Manual page 35

Reference Manual
00809-0000-4851 Rev AD
December 2023
Figure 3-5 – Elevated Zero
Calibration Example
Figure 3-5a – Example for Elevated Zero
Calibration (English Units)
Calibration
Range 2 with Zero Elevation for a calibration of
–120 to –20 inH O (100 inH
2
1. Calibrate the transmitter to 0 to 100 inH
described in the Zero Based Calibration Procedure.
2. Consult Figure 3-8b to help determine typical coarse
zero select jumper position. If necessary, reposition
jumper using the Coarse Zero Select Jumper
Position Selection Procedure.
For this example:
% Zero Offset = (-120 inH
Position the jumper to the MID ZE position.
3. Apply -120 inH
2
(as marked on the transmitter sensor module) and
adjust the zero until the transmitter output reads 4mA.
DO NOT USE THE SPAN ADJUSTMENT.
NOTE
Applying 120 inH O to the low side process connection (as
2
marked on the transmitter module) will give the same result.
4. Apply -20 inH O to the high side process connection
2
(as marked on the transmitter sensor module). Verify
the output reads 20mA. If necessary, adjust the span.
Recheck the zero after any span adjustment.
NOTE
Applying 20 inH O to the low side process connection (as
2
marked on the transmitter module) will give the same result.
Rosemount 2151N
O span)
2
O /250 inH O)*100 = -48%
2 2
O to the high side process connection
O as
2
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