16
en
DPA/DRT
•Operation
General
The DPA/DRT allows you to monitor the difference between two
resistance values using two independent trip points. They are, typically,
used to monitor the difference in temperatures measured by two Pt100
RTDs, the only restriction being that the temperature measured by R
1
must be greater than the temperature measured by R
.
Setup
The alarm relay coils operate according to each setpoint/deadband
configured via front panel multiturn potentiometers. Internal push
fit jumpers determine the alarm type (high or low acting) and coil
energisation (normally energised/de-energised).
DPA/DRT block diagram.
Alarm 1
Power
Supply
Alarm 2
Differential
Resistance
R
1
R
2
Note: R1 must be
greater than R2
