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Voltage and Temperature Measurements 2-19
Measuring voltage and temperature
NOTES The following procedure assumes factory default conditions (see Table 1-2 in
Section 1 ). Details on using other settings and front panel operations are provided in
Section 3 through Section 8 of this manual.
Any time the internal temperature of the Model 2182 changes by 1˚C or more, the
10mV and 100V ranges will need to be calibrated (see “
Performance considerations ,
ACAL procedure ” for details).
Whenever the LEMO connector of the Model 2107 Input Cable (or customized cable)
is disconnected from the input of the Model 2182 for a long period of time, the input
connectors will have to be cleaned to remove oxidation (see “
Cleaning input
connectors ” in Section 1 ).
Do not use both channels to measure temperature. The electrical connection between
the two thermocouples will cause erratic temperature readings.
Clean copper-to-copper connections minimize thermal EMFs. However, when
measuring very low voltages, there may still be enough thermal EMFs to corrupt the
measurement. In this case, use the Relative feature of the Model 2182 to null out that
offset. See “
Nulling thermal EMFs ” which follows the basic measurement procedure.
Step 1 Connect test circuit to Model 2182
As explained in “ Connections ”, connect the test circuit to the input of the Model 2182.
Figure 2-4 through Figure 2-9 show connections for voltage and temperature measurements.
Step 2 Configure temperature (if applicable)
If temperature measurements are going to be performed, configure temperature as previously
explained in “ Temperature configuration .”
Step 3 Measure Channel 1
If Channel 1 is connected to measure voltage, press DCV1. If connected to measure
temperature, press TEMP1. Observe the reading on the display. The “CH1” annunciator
indicates that Channel 1 is selected.
Step 4 Measure Channel 2 (if applicable)
NOTE Channel 2 inputs must be referenced to Channel 1 LO.
If Channel 2 is connected to measure voltage, press DCV2. If connected to measure
temperature, press TEMP2. Observe the reading on the display. The “CH2” annunciator
indicates that Channel 2 is selected.