How To Adjust the Trip Point Hysteresis on Type
623H
Chapter Four: Operation
44
How To Adjust the Trip Point Hysteresis on Type 623H
Hysteresis is built into the operation of the two alarm relays on the Type 623H to help
compensate for the noise inherent in all systems. Without hysteresis, the noise may cause the
alarm relays to chatter (repeatedly switch states). On the Relay board in the types 623H unit are
jumpers J11 (for Trip Point A) and J10 (for Trip Point B). You can adjust the amount of
hysteresis separately for each alarm relay by placing shorting jumpers on J11 and J10.
Refer to
Hysteresis
, page 37, for an explanation of the effect of different amounts of hysteresis.
To change the transducer’s configuration:
1. Turn off power to the unit and disconnect the cables from TB1 and TB2.
2. Push down on the colored ring on the endcap, turn it about ¼ turn counterclockwise, and
lift it off the endcap.
3. Remove the two screws on each side of TB1.
4. Lift off the graphics panel.
The relay board with jumpers J10, J11, J12, J13, J15, and J16 is now accessible.
Refer to Figure 10, page 41, and Figure
Error! Bookmark not defined.
1, page 42, for
the location of jumpers J10 and J11.
5. Move the shorting jumpers on jumper J11 to change the hysteresis of Trip Point A and
move the shorting jumpers on jumper J10 to change the hysteresis of Trip Point B.
Refer to Table 14 for the correct position of the shorting jumpers.
Shorting Jumper Positions for Hysteresis
Hysteresis (% of FS)
Trip Point A
Trip Point B
0.1%
J11: 2 - 4
J10: 2 - 4
0.2%
J11: 4 - 6
J10: 4 - 6
0.5%
Factory-set position
J11: 1 - 3
J10: 1 - 3
1%
J11: 3 - 5
J10: 3 - 5
2%
J11: 3 - 4
J10: 3 - 4
Table 14: Shorting Jumper Positions for Hysteresis
