Fluke 74X Series, Руководство по калибровке

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74X Series
Calibration Manual
26
RTD Measure, Three-Wire
Proceed as follows to verify the three-wire RTD measure function. If a 5500A is not
available, substitute a variable resistance source such as a General Resistance RTD-100
RTD Simulator and a DMM to measure the variable resistance source accurately. Use the
resistance equivalents shown in Table 16.
1. Connect the UUT to the 5500A as shown in Figure 13.
2. Set the UUT to the RTD Measure function, Pt100 (385), ITS-90 scale, 3-Wire
termination.
3. Set the 5500A to RTD, Pt100 (385) at -180
°
C, ITS-90 scale, and comp four-wire to
"OFF" position. Set the 5500A to [Operate].
4. Observe the reading on the UUT and check to see if it is within the range shown
under the appropriate column in Table 16.
5. Continue through the test points.
6. When you are finished, set the 5500A to [Standby].
TC
mA mA V V
RTD
RTD
SOURCE 300V
MAX
30V
MAX
30V
MAX
30V
MAX
MEAS
CAT
5500A CALIBRATOR
20V PK
MAX
HI
LO
TC
TRIG
OUT
1000V
RMS
MAX
20V
RMS
MAX
1V PK
MAX
20V PK
MAX
NORMAL AUX
SCOPE
V, ,
RTD
A, -SENSE,
AUX V
200V PK
MAX
3 WIRE RTD
FLUKE 5500A CALIBRATOR
FLUKE 74X
gb14f.eps
Figure 13. Three-Wire RTD Measure Verification Connections
Table 16. RTD Measure Verification (100W Pt (385), Three-Wire Connection)
Input
°
C (Resistance) 1-Year (
°
C ) 2-Year (
°
C )
-180
°
(27.096
Ω
) -179.3 to -180.7 -179.1 to -180.9
100
°
(138.505
Ω
) 99.1 to 100.9 98.8 to 101.2
780
°
(369.712
Ω
) 778.8 to 781.2 778.6 to 781.4