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Set the MEASUREMENT/CALIBRATION switch to the CALIBRATION position.
To recall the comparison value (contents of Register 8), enter;
RCL
8
To set a new comparison value, for example 20.0, enter;
2 0.0
STO 8
After checking and/or setting the comparison value, remember to return the
MEASUREMENT/CALIBRATION switch back to the MEASUREMENT position.
6.4 CHECKING MINIMUM AND MAXIMUM READINGS
The CL521 stores the minimum and maximum values shown on the display, starting
from the time it is switched on. The minimum and maximum values can be recalled by
pressing the MIN or MAX keys, respectively. The MIN and MAX functions are indicated
by the letters "L" (low) and "H" (high) at the left edge of the display. The values are reset
to the current display value when the RESET key is pressed or a new main function is
selected.
6.5 RETURNING TO NORMAL MEASUREMENT MODE
To return to the normal measurement mode from another measurement function, press
the NORM key.
SECTION 7 THERMOCOUPLE SIMULATION AND MILLIVOLT
CALIBRATION
7.1 PRINCIPLE OF THERMOCOUPLE SIMULATION
Thermocouple simulation refers to the process of replacing a thermocouple with a device
which mimics the functioning of the thermocouple. The simulator is given a temperature
value, which it then converts into a corresponding potential. To the measuring device,
the simulator appears as a thermocouple at the set temperature. Thermocouple
simulation can be used to check temperature indication devices, plotters, transmitters,
and other equipment related to a thermocouple probe.
If thermocouple extension cable is used in the measuring circuit, an extra thermovoltage
will be created at the point where the simulator is connected to the extension cable. The
simulator must be able to compensate for this extra potential.
7.2 THERMOCOUPLE SIMULATION
7.2.1 Connection and Selection Compensation Modes
All reference junction compensation modes of the CL521 can be used in thermocouple
simulation. Compensation is needed for thermopotentials arising from simulator
connection into the measuring circuit. The choices are;
A) Internal reference junction compensation, CJ MODE = INT
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