4.9.9
TEMP
erature
COMP
ensation
Temperature compensation is included in the DO7PLUS and should be used when
measurements are required to be referenced to a set temperature, normally 20
q
C. This is
particularly useful when measuring materials with a high temperature coefficient such as
copper. As the ambient temperature varies so will the resistance value of the copper. Using
the temperature compensation mode references all values back to a reference temperature.
The DO7PLUS displays both the temperature compensated value, and the true resistance
value measured, together with the reference temperature and the actual measurement
temperature. This ensures that the user has all the measurement information and reference
conditions readily available.
Fig:4.9.9 Measurement Display screen in temperature compensation mode
Setting the Temperature Compensation Parameters
From the MENU window F3 the temperature compensation can be switched ON or OFF. The
measurement temperature can also be set to either MANUAL or Pt100. If the Pt100 option is
selected then the ambient temperature will be measured with a Pt100 temperature sensor
(available as an option). If the Manual option is selected using the right navigation arrow, then
a new window permits the entry of the required temperature over the range 0 to 100
q
C
HINT:
Once the manual temperature is selected this temperature value is used for all
measurements. This mode should only be used in known stable ambient conditions.
If the Pt100 option is chosen then a Pt100 sensor should be connected to the front panel
socket see section 2.2.1 The Pt100 sensor will continuously measure the ambient
temperature and correct the measured resistance values accordingly.
HINT:
For best measurement results always use the Pt100 mode.
INSTRUMENT MENU
TEMP COMP:
OFF
ON
MANUAL
COEFF Cu
(3930)
REF TEMP
20.0
q
C
ESC
OK
TEMP: PT100
MANUAL 18.00
q
C
ESC
OK
TEMP
COEFF: Cu (3930)
Al (4030)
USER 1
USER 2
ESC
OK
RANGE: 6k
100μA
(+VE)
+5.0589 k
@ +20.0
q
C
FUNCTION STATUS
TRIGGER
LIMITS
FILTER
SETTLING
DATA LOG
SING
OFF
OFF
OFF
OFF
BATT
(3V)
BATT
(6V)
98%
92%
STOP
RANGE
CURR MENU SET UP
Rx +5.0281 k
@ +18.00
q
C
11
Operating Instructions
Digital Microhmmeter Type DO7 PLUS
27