Table of Contents
Advertisement
16-16
Verifying temperature
Thermistor and RTD temperature readings are derived from resistance measurements
respectively. For that reason, it is not necessary to independently verify the accuracy
of temperature measurements. As long as the resistance function meets or exceeds
specifications, temperature function accuracy is automatically verified. However,
temperature verification procedures are provided below for those who wish to separately
verify temperature accuracy.
RTD temperature
1.
2.
3.
4.
Connect the precision decade resistance box
INPUT and SENSE jacks using four-wire connections. (See
connecting scheme.) Be sure the INPUTS switch is in the FRONT position.
Configure the Model 2790 temperature function for °C units and RTD temperature
sensor (α=0.00385) as follows:
a.
Press SHIFT then SENSOR. Note the unit displays the temperature units:
UNITS: C.
b.
Press ENTER.
c.
Using the cursor and range keys, set the display as follows: SENS: 4W-RTD.
d.
Press ENTER, and note the unit displays: TYPE: PT100.
e.
Using the cursor and range keys, set the unit for the following display: TYPE:
PT385.
f.
Press ENTER to complete the temperature configuration process.
Select the temperature function by pressing the TEMP key.
Set the decade resistance box to each of the values shown in
that the temperature readings are within the required limits.
Table 16-7
Four-wire RTD temperature verification reading limits
Applied resistance*
22.80Ω
100.00Ω
313.59Ω
*Based on α = 0.00385. See text.
Model 2790 SourceMeter
(Table
Reading limits
(1 year, 18°C to 28°C)
-190.06 to -189.94°C
-0.06 to +0.06°C
599.94 to 600.06°C
®
Switch System Reference Manual
16-1) to the Model 2790
Figure 16-5
for similar
Table 16-7
and verify
Advertisement
Table of Contents
