Thermo Fisher Scientific Alpha COND 1000 - Manual (Page 42)

12.5 Appendix 5 - Simple Explanation on the Function of Hysteresis
SP1 Set to LO
10.0 10.5 100.0 100.5
RELAY OFF
HYSTERESIS BAND
FORWARD DIRECTION
REVERSE DIRECTION
SP1 SP2
RELAY ON
SP2 Set to HI
mS
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.