Standard Performance: Split Range Input, Reverse Action; To 12 Ma Input Signal; 12 To 20 Ma Input Signal - Emerson Fisher 846 Instruction Manual

Type 846 and Model 3311
electronic circuit board identifies reverse-acting
units. Refer to Action under the heading Electronic
Circuit Board in Section 6 for more information on
reverse acting units.
2. Apply an input of 4.0 mA (V
adjust the zero screw to achieve the desired upper
limit of the output range. The 4 mA point must be
between 0.6 and 2.0 bar (9.0 and 30.0 psi). The
output increases with clockwise rotation of the zero
screw.
3. Apply an input of 20.0 mA (V
adjust the span screw to achieve the desired lower
limit of the output range. The span must be at least
0.7 bar (11.0 psi). The lower limit of the 20.0 mA
setting is 0.03 bar (0.5 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, Reverse Action

4 to 12 mA Input Signal

Use the following procedure on reverse action units
to achieve a 1.0 to 0.2 bar (15 to 3 psi) output signal
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, except for step 2. In place of
step 2, confirm that the unit is reverse acting. A red
electronic circuit board identifies reverse-acting
units. Refer to Action under the heading Electronic
Circuit Board in Section 6 for more information on
reverse acting units.
2. Apply an input of 4.0 mA (V
the zero screw to achieve an output of 1.0 bar (15.0
psi).
3. Apply an input of 12.0 mA (V
adjust the span screw to achieve an output of 0.2
bar (3.0 psi).
4. Repeat steps 2 and 3 to verify and complete the
calibration.

12 to 20 mA Input Signal

Use the following procedure on reverse action units
to achieve a 1.0 to 0.2 bar (15 to 3 psi) output signal
for a 12 to 20 mA input signal:
3–4
= 1.0 V), and
m
= 5.0 V), and
m
= 1.0 V), and adjust
m
= 3.0 V), and
m
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, except for step 2. In place of
step 2, confirm that the unit is reverse action. A red
electronic circuit board identifies reverse-acting
units. Refer to Action under the heading Electronic
Circuit Board in Section 6 for more information on
reverse acting units.
2. Apply an input of 4.0 mA (V
the zero screw to achieve an output of 1.0 bar (15.0
psi).
3. Apply an input of 12.0 mA (V
adjust the span screw to achieve an output of 0.2
bar (3.0 psi).
4. Maintain the input of 12.0 mA (V
adjust the zero screw to achieve an output of 1.0 bar
(15.0 psi). The unit may not turn up this high; if it
does not, go to step 7.
5. If the output reaches 15.0 psi in step 4, apply an
input of 20 mA, and adjust the span screw to
achieve a 3.0 psi output. Apply an input of 20 mA
(V = 5.0 V), and note the error (the actual reading
m
versus 3.0 psi). Adjust the span screw to overcorrect
the error by a factor of two. For example, if the
reading was 2.95 psi, adjust the span screw to
achieve an output of 3.05 psi.
6. Repeat steps 4 and 5 to verify and complete the
calibration.
7. If the 12.0 mA (V = 3.0 V) cannot be adjusted to
m
1.0 bar (15.0 psi) in step 4, turn off the air supply.
Remove the module final assembly from the
housing. Place the range jumper in the Lo position
for Low Range, as shown in figure 6-5. Replace the
module final assembly. Turn on the air supply.
8. Apply an input of 12.0 mA (V
adjust the zero screw to achieve an output of 1.0 bar
(15.0 psi).
9. Apply an input of 20 mA (V
the error (the actual reading versus 3.0 psi). Adjust
the span screw to overcorrect the error by a factor of
two. For example, if the reading was 2.95 psi, adjust
the span screw to achieve and output of 3.05 psi.
10. Repeat steps 8 and 9 to verify and complete the
calibration.
Instruction Manual
Form 5739
February 2002
Note
= 1.0 V), and adjust
m
= 3.0 V), and
m
= 3.0 V), and
m
= 3.0 V), and
m
= 5.0 V), and note
m