TECPEL CL-327A Manual page 25

to the changes of the reference junction compensation). Pressing the 〔T.DISP〕key once more, LCD shows
the present room temperature value in assistance districts part of the LCD.
7.6 Simulate Sourcing RTD
 Firstly, the calibrator sources a resistance signal by receiving the resistance-measuring current I supplied
from the device being calibrated (such as a resistance meter) and then delivering the voltage V
proportional to the preset resistance R between the output terminals, and thus producing the equivalent
resistance R =V/I. Consequently, the calibrator sources the signal correctly only for such devices that
employ this method of measurement.
 The allowable range of the resistance measuring current I that the calibrator receives from a resistance
measuring device under calibration is rated as 0.1 to 3mA at PT100,Cu10,Cu50, 0.05 to 0.3mA at
PT200,PT500,PT1000. To ensure accuracy, the resistance measuring current I from the device under
calibration shall be strictly confined within the range. For further details, see Chapter 24, "Specification".
 Any resistance signal being sourced does not include the resistance component of the lead cables for
source. The whole resistance, when measured at the ends of the lead cables for source, is given by
adding the resistance of the lead cables (approximately 0.1Ω on a round-trip basis) to the sourced
resistance signal. For source of precise resistance signals, use three-wire or four-wire connection.
Step 1: Using the〔RTD〕key, select RTD function. Using the〔RANGE〕key, select a desired RTD range from
PT100, PT200, PT500, PT1000, Cu10, Cu50. The selected function and the default range source value and
unit shall be shown in the main districts part of the LCD. Types of RTD shall be shown in the middle part of the
LCD.
Step 2 :Set the output value digit by digit using each pair of〔〕/〔〕keys.
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