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11.3 Appendix 3
Simple Explanation on the Function of Hysteresis
The controller relay activates when the set-point is reached. In the
reverse direction, it does not de-activate when the value reaches the
set-point. Instead, it continues to be active till the value reaches the
amount set by the Hysteresis band.
4.0
4.5
9.5
10.0
7.0
RELAY OFF
HYSTERESIS BAND
(DEFAULT = 0.5 pH)
FORWARD DIRECTION
REVERSE DIRECTION
SP1
SP2
RELAY ON
SP1 Set to LO
SP2 Set to HI