Omega Vehicle Security DP97 - Manual (Page 6)

3. OPERATION
Ensure that the instrument is connected to a suitable supply or has charged batteries
and that the required input connections are made.
Switch “on” using the rear mounted rocker switch.
The display will show “Pr 2.1” or “Pr 1.4” the programme designation. There is a short
delay while internal checks are carried out, then the input A value will be displayed.
i)
To read sensor temperature directly
a) PRT input A is automatically selected at switch-on. Brief repeated
key presses will step through the various functions or holding
the key depressed will auto repeat (scroll through); this applies
to the other functions as well.
Note: If for any selected channel, the sensor is either not connected or has a faulty
connection (including sensor open-circuit), the LED display will show:- “Err 3”
Press any button to resume normal operation (either select another channel or rectify
any fault and continue intended use).
b) Press CHANNEL to select inputs A,B or A-B (differential).
c) Press UNITS to display the desired units °C, °F, K, or
Ω
ii)
To read Differential Temperature
The difference in temperature between two PRT sensors can be obtained
by displaying A-B.
Ensure that the necessary sensors are connected to both A and B inputs
as required.
Press CHANNEL to select A-B
Press UNITS to display the desired units
The value now displayed is the difference between the input A and input B
(A-B) for the sensor type indicated.
Null Feature
For calorimetry and other applications to optimise the precision of differential
measurements, probe tolerances can be nulled by pressing the NULL key when in A-B
mode. This gives an A-B reading of zero when pressed regardless of any real difference
value.
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