Emerson Fisher 4194HA, Инструкция по эксплуатации

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Instruction Manual
D200156X012
4194HA, HB, HC Controllers
July 2018
44
Refer to the installation procedures when reinstalling the unit.
Note
In the following procedures, adjust the proportional band knob between DIRECT and REVERSE. If this is done, it will be necessary to
set the proportional band knob to 400 DIRECT or REVERSE (direct or reverse action) before replacing the proportional band
indicator cover.
Replacing the Process Differential Pressure Scale
CAUTION
Take care not to bend the process indicator or the set point adjustment while performing the following procedure.
Refer to figure 5‐3.
Figure 5‐3. Changing the Scale
W3440 W3492
1. Adjust the set point adjustment manually or with the remote set point pressure to 50 percent of scale range.
2. Remove the four self‐tapping screws (key 37).
3. Slide the process scale (key 61) so the top of the slot touches the set point adjustment. Deflect the lower portion of
the slot and carefully slide the scale upward and off, clearing the set point adjustment as shown in figure 5‐3.
4. To install the replacement scale, bend the lower part of the slot slightly so the scale slides downward over the set
point adjustment and under the process indicator.
5. Secure the scale with the four self‐tapping screws (key 37).
6. If the controller has the remote set point option, perform the appropriate remote set point calibration procedure.
7. Perform the appropriate process indicator zero‐and‐span adjustment and the flapper alignment in the calibration
procedures in Section 3 or 4.
Replacing the Relay
1. Loosen the two captive screws holding the relay (key 50) in place.