IDEC SmartRelay functions
162 IDEC SmartRelay Manual
Parameters On and Off
The on threshold On and the off threshold Off can be
provided by the actual value of another already-programmed
function. You can use the actual values of the following
functions:
• Analog comparator (actual value Ax - Ay, see Chapter
4.4.18)
• Analog trigger (actual value Ax, see Chapter 4.4.16)
• Analog amplifier (actual value Ax, see Chapter 4.4.20)
• Analog multiplexer (actual value AQ,
see Chapter 4.4.
26)
• Analog ramp control (actual value AQ, see Chapter
4.4.27)
• Analog math (actual value AQ, see Chapter 4.4.30)
• PI controller (actual va
lue AQ,
see Chapter 4.4.28)
• Up/down counter (actual value Cnt, see Chapter 4.4.13)
Select the required function by the block number.
Timing diagram
Functional description
The internal counter increments (Dir = 0) or decrements (Dir
= 1) by
one count with every positive edge at input Cnt.
You can use input R to reset the internal count value to the
start value. As long
as R = 1, the output is also 0 and the
pulses at input Cnt are not counted.
If retentivity is not set, output Q and the expired time are
reset after a power failure.
Q is set o
r reset depending on the current value at Cnt and
the set
thresholds. See the calculation rule below.
Calculation rule
• If the On threshold Off threshold, then:
Q = 1, if Cnt On
Q = 0, if Cnt < O
ff.
• If the On threshold < Off threshold, then Q = 1,
if On
Cnt < Off.