Instruction Manual
D102005X012
846 Transducer
June 2017
19
Use the following procedure with a multirange performance unit to achieve the desired direct action output span for a
4 to 20 mA input signal:
1. Perform steps 1 through 9 of the calibration procedure for Standard Performance: Full Range Input, Direct Action.
2. Apply a 4.0 mA (Vm = 1.0 V) signal, and adjust the zero screw to achieve the desired lower limit of the output range.
The lower limit must be between 0.03 and 0.6 bar (0.5 and 9.0 psi). The output increases with clockwise rotation of
the zero screw.
3. Apply a 20.0 mA (Vm = 5.0 V) signal, and adjust the span screw to achieve the desired upper limit of the output
range. The span must be at least 0.4 bar (6.0 psi). The maximum upper limit is 2.0 bar (30.0 psi). The output
increases with clockwise rotation of the span screw.
4. Repeat steps 2 and 3 to verify and complete the calibration.
Standard Performance: Split Range Input, Direct Action
WARNING
Refer to the WARNING at the beginning of the Maintenance section.
4 to 12 mA Input Signal
Use the following calibration procedure to produce a 0.2 to 1.0 bar (3 to 15 psi) output span for a 4 to 12 mA input
signal:
1. Perform steps 1 through 9 of the calibration procedure for Standard Performance: Full Range Input, Direct Action.
2. Apply an input of 4.0 mA (Vm = 1.0 V), and adjust the zero screw to achieve an output of 0.2 bar (3.0 psi).
3. Apply an input of 12.0 mA (Vm = 3.0 V), and adjust the span screw to achieve an output of 1.0 bar (15.0 psi).
4. Repeat steps 2 and 3 to verify and complete the calibration.
12 to 20 mA Input Signal
Use the following calibration procedure to produce a 0.2 to 1.0 bar (3 to 15 psi) output span for a 12 to 20 mA input
signal:
Note
There may be some span interaction with zero in this range, and the following steps compensate for this.
1. Perform steps 1 through 9 of the calibration procedure for Standard Performance: Full Range Input, Direct Action.
2. Apply an input of 4.0 mA (Vm = 1.0 V), and adjust the zero screw to achieve an output of 0.2 bar (3.0 psi).
3. Apply an input of 12.0 mA (Vm = 3.0 V), and adjust the span screw to achieve an output of 1.0 bar (15.0 psi).
4. Maintain the input of 12.0 mA (Vm = 3.0 V), and adjust the zero screw to achieve an output of 0.2 bar (3.0 psi). The
unit may not turn down this low; if it does not, go to step 7.
5. If the output reaches 0.2 bar (3.0 psi) in step 4, apply an input of 20.0 ma (Vm = 5.0 V) and note the error (the actual
reading versus 15.0 psi). Adjust the span screw to overcorrect the error by a factor of two. For example, if the
reading was 0.9 bar (14.95 psi), adjust the span screw to achieve an output of 1.1 bar (15.05 psi).
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