Extech Instruments PRC70, Руководство пользователя

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7.9 Sourcing Contact Output
Switch the output terminals ON or OFF using the contact output function. The contact-switching device is an FET.
Step 1:
Using the function key (FUNC) , select the contact output source function. The LCD shows the default value (10Hz)
and the “ “ switch symbol.
Step 2:
Using the (RANGE) key, select a frequency (100Hz, 1KHz, 10 KHz, 100KHz).
Step 3:
Set the output value digit by digit using each pair of 〔
S
〕 / 〔
T
〕 output setting keys.
Each pair of
〔
S
〕
/
〔
T
〕
keys corresponds to each digit of the LCD reading. Each press of the
〔
S
〕
/
〔
T
〕
key increases
or decreases the digit. Increasing the digit from 9 or decreasing it from 0 causes the digit to overflow or underflow, allowing
the output value to be set without interruption. Holding down the
〔
S
〕 / 〔
T
〕 key changes the digit quickly. The value won’t
change if it is increased or decreased to the Maximum or Minimum value.
Step 4:
Pressing the (ON) key causes the SOURCE indicator on the LCD to change from ‘’OFF‘’ to ‘’ON ‘’.
Step 5:
To switch the output OFF, press the (ON) key again. The ‘’OFF‘’ icon appears on the LCD and signals sourced
between its terminals will be switched OFF.
Notes:
z The contact output source function is unavailable if the frequency measurement function is ON.
z The amplitude and pulse number cannot be set when in the contact output mode.
z The contact output is polarized. Generally, connect the positive polarity with the high (H) jack of the calibrator and the
negative polarity with the low (L) jack.
z Note that the maximum allowable current for the contact output is 50mA.
7.10 Zero-off function
For any DC voltage, DC current, Resistance (ohms), TC (thermocouple) or RTD range, pressing the (ZERO) key initializes
the preset source value.
In the frequency, pulse, and contact output modes, the
(ZERO) key is unavailable.