Grant Instruments LTC4 - Manual (Page 23)

LTC4 31115 V1
Operating Manual Page 22
www.grantinstruments.com
5.3.4 Configuring high and low temperature alarms
There are three functions in the alarm menu.
1. A high alarm function, which causes an alarm condition when the bath
temperature goes higher than the alarm value. The alarm value can be set as a
fixed temperature above the set temperature or a deviation offset value above the
set temperature. Below is an example of a high temperature deviation alarm,
where the deviation value has been set to 5
˚C.
2. A low alarm function, when the bath temperature goes lower than the alarm
value. The alarm value can be set as a fixed temperature below the set
temperature or a deviation offset value below the set temperature. Below is an
example of a low temperature fixed alarm, where the fixed temperature value has
been set to -20
˚C.
3. A hold-off time can be entered, which is a user adjustable time of between 0 and
21mins for which the alarms remain muted after either button has been pressed
to acknowledge an alarm condition. If the bath returns to the value such that the
alarm level is not exceeded the alarm will cancel. However, if the temperature
remains outside the alarm level the alarm condition will re-occur after this hold-off
time.
Liquid temp
Time
5 10 15

Temp
Alarm
Value -20
˚C
Set temp -10 ˚C
Low temperature fixed alarm.
Liquid temp
Set
temperature
Deviation
5°C
Temp
Time
5 10 15
High temperature deviation alarm.


Alarm value