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3. Connection Diagrams & Instructions
A. Sourcing Resistance
1. Select the RTD mode.
2. Connect device under test as shown.
3. In the RTD mode, use the RTD key to choose the desired range.
4. The PTC 400 is able to handle up to a 3 mA excitation on the Resistance Simulation Range.
Exceeding these limits will result in a warning on the display.
Figure 1.
B. Sourcing a Thermocouple Signal
TC wire must be used to achieve an accurate calibration.
Figure 2.
Note:
For best accuracy allow a 10 minute warm-up period after the PTC 400 is turned on.
C. Measuring Temperature Using a Thermocouple
Figure 3.
D. Measuring Resistance (RTDs)
When measuring resistance (ohms) there are 3 choices when using the PTC 400. The choices
are 2-wire, 3-wire, and 4-wire measurements. While 4-wire offers the highest accuracy, most
industrial RTDs are a balance 3-wire. Figure 4 shows how to hook up the PTC 400 for the 3
types of measurements.
1. Choose the desired RTD/ohms range by first pressing the “RTD” key to get into the RTD mode.
Continue to press the “RTD” key to step through all of the RTD choices.
