Instruction Manual
D200156X012
4194HA, HB, HC Controllers
July 2018
47
Figure 5‐5. Link Locations
LINK 4
LINK 4 ADJUSTMENT
LINK 2
LINK 2 ADJUSTMENT
LINK 3 ADJUSTMENT
LINK 3
W3442‐1
Link 1
Note
Before performing the following link 1 maintenance steps, disconnect supply pressure from the controller.
1. Note where the link is connected. Disconnect the link from the drive arm and from the process indicator assembly.
Remove the link. Then, install the replacement link.
during the process indicator zero‐and‐span adjustment, the indicator will not travel full scale even after full span
adjustment, move the link to the bottom hole. If the indicator has too much travel, move the link to the top hole.
3. Remove the two screws (key 6) and lift off the proportional band indicator cover (key 36).
4. Move the set point adjustment manually, or with remote set point pressure, to 50 percent of the scale range. Set
the proportional band between DIRECT and REVERSE.
adjustment locking screw. Then, adjust the fine zero adjustment to align the indicator and subassembly.
6. With a regulated air supply, adjust process differential pressure to 50 percent of process scale range. The process
indicator should be within
±
3 percent of mid‐range on the scale. If not, loosen the two screws in link 1 and move the
process indicator to within
±
3 percent of mid‐range on the scale. Then, tighten the screws.
7. Perform the controller calibration procedure and, if necessary, the appropriate remote set point calibration