Split Range Operation - Emerson Fisher 546NS Instruction Manual

Instruction Manual
D103425X012

Split Range Operation

The 546NS transducer is suitable for two‐way split range operation. In a two‐way split the milliampere (mA) or voltage
output signal of a single control device is split between two transducers electrically connected in series. Although each
transducer receives the full signal, it is calibrated to provide a full output pressure range of 0.2 to 1.0 bar (3 to 15 psig)
or 0.4 to 2.0 bar (6 to 30 psig) to the control valve with one‐half the input signal. Because the transducer operates on
only one‐half of the normal input span, the feedback bellows must be changed to compensate for the shorter span.
Change the bellows as described in the replacing feedback bellows assembly procedure in the Maintenance section.
Table 6 indicates which bellows is required for your conditions. Reset the span and zero adjustments to the split range
values. Note that these transducers cannot provide a three‐way split range.
Table 6. Feedback Bellows Output Pressure Range
OPERATION
(1)
1 to 9 V
Full Range 4 to 20 mA
10 to 50 mA
4 to 12 mA or 12 to 20 mA
Split Range 10 to 30 mA or 30 to 50 mA
1 to 5 VDC or 5 to 9 VDC
1. Temperature compensated circuit.
INPUT SIGNAL, DC
BELLOWS SIZE
Full
Bar Psig
0.2 to 1.0 3 to 15
- - - - - -
546NS Transducer
June 2021
Half
Bar Psig
0.4 to 2.0 6 to 30
0.2 to 1.0 3 to 15
13