Masibus PCE-MCA 50, Руководство пользователя

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➢
Manually Entered:
To be used when The Reference Junction temperature is fixed to
a temperature. The Reference Junction temperature is controlled
and the controller’s set point to desired temperature.
Note: this method is of use only if the accuracy of the controller is better than PCE-
MCA 50
’s own Reference Junction.
A compensation box is used and the Reference Junction
temperature setting is set to desired temperation.
There is no Reference Junction compensation in the
measuring/simulation circuit, but you want to manually enter
another Reference Junction temperature.
Connection when measuring/simulating
Thermo-voltages using a temperature controller and either
of the following Reference Junction compensation method:
“Manually Entered”
➢
Error situations
The easiest way to avoid errors in thermocouple measurement
and simulation is to check carefully the used wiring and the
Reference Junction mode. The following table describes the
typical error situations and possible causes/corrections when
working with thermocouples:
PROBLEMS CAUSE
PCE-MCA 50 (or the
instrument under test when
simulating thermovoltages)
measures the
temperature/millivolt signal,
but the displayed
temperature reading is all
wrong.
(The error may vary from 0
to about ±50°C depending
on the type of the error)
• The thermocouple type selected in
PCE-MCA 50
does not correspond with the used
Thermocouple.
• The selected Reference Junction
mode is
not in accordance with the used
wiring.
• Extension or compensation cable
type or
connections are incorrect.
• The polarity of the cables are
incorrect.
PCE-MCA 50 (or the
instrument under test)
displays random readings
during
Thermocouple
measurement.
• Incorrect connections.
• The wiring is broken.
• Interference from a mobile phone or
a radio transmitter affects the
measurement.
5.3.2 Parallel Functions in PCE-MCA 50