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3.5 Setting the Control Limit
The control limit can be set over the full scale of the
miniCHEM-Temp
, as a “too
high” or a “too low” trip point. The hysteresis around this set point can be also be
adjusted, if necessary. See section 3.5.3 for an explanation of hysteresis.
3.5.1
Setting the limit value
1.
Switch the
miniCHEM-Temp
to
SET LIMIT
.
The control limit value is now displayed. Note that the Alarm LED and
(optional) output relay are now disabled. The 4-20mA or 0-1V outputs are
still active, and proportional to displayed value.
2.
Adjust the
LIMIT
control until the display reads the desired trip point value.
3.5.2
Setting the alarm/control direction
The control limit can be set as a “too high” or “too low” trip point using the
Lo/Hi
Control
jumpers in the terminal area. The
miniCHEM-Temp
must be switched
OFF before changing jumper settings.
The jumper settings for a “too low” trip point are…
Low High
The jumper settings for a “too high” trip point are…
Low High
