dS2824
dS2824
User Manual v4.09
To demonstrate a real world example, take the analog example above where we compared A1
with 1000 to operate R2. Whilst this would work its a not a good solution as the relay would
jitter badly when A1 was hovering between 999 and 1000. What we need is some hysteresis.
To do that we will use R2 in its own equation.
(A1<1000&!R2)|(A1<1234&R2)
Assume R2 in inactive (off). The 2
nd
half of the equation (A1<1234&R2) will have no effect.
So when A1 falls below 1000 the relay comes on. Now the 2
nd
half of the equation is true, and
will stay true until A1 climbs above 1234.
So the relay becomes active when A1 is below 1000 and inactive above 1234.
We have hysteresis!
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