Extech Instruments PRC50 User Manual page 11

5.3.1 Manually Set 25%, 100% 4–20 mA Function
The source value in 4 mA or 16mA increments or decrements can be set within the 4–20 mA current range.
Step 1: In the DC current function, press the〔25%100%〕key to display "25%SET" on the lower part of the screen, and
press it again to display "100%SET". The default source value will be displayed.
Step 2: Using each pair of 〔 〕/〔 〕output setting keys, set the signal in a step-by-step manner. In 25% set point mode,
set the signal in 4 mA increments in the order 4-8-12-16-20 with each press of the key. In 100% set point mode, set the
signal in 16 mA increments in the order 4-20 with each press of the key. Pressing the〔ZERO〕key initializes the signal set
point to the default value (4mA).
Step 3: Pressing the〔ON〕key causes the indicator on the LCD to change from ''OFF'' to ''ON ''. The calibrator sources the
preset 4–20 mA current signal between the output terminals.
Step 4: To turn off the output, press the〔ON〕key again. The'' OFF ''icon appears on the LCD and no signals are sourced
between the terminals.
5.3.2 Auto-stepping and auto-sweeping 4-20mA function
The user can set a 4–20 mA range within which to source current in 4-20mA increments or decrements in auto-stepping
mode or in auto-sweeping mode. 80 seconds are required to finish a 4-20mA cycle in auto-sweeping mode and 20 seconds
are required for auto-stepping mode.
Step 1: In the DC current mode, press the 〔
of the screen, and press it again to display the auto-sweeping mode signal "
Step 2: Pressing the (ON) key causes the indicator on the LCD to change from ''OFF'' to ''ON ''. The calibrator sources the
default 4–20 mA current signal between the output terminals.
Step 3: Pressing the (START) key starts the auto-stepping and auto-sweeping mode. The "RUN" icon is displayed in the
lower part of the LCD.
Step 4: Pressing the (START) key again stops the auto-stepping and auto-sweeping mode. The "RUN" icon switches OFF.
Step 5: Pressing the (ON) key stops sourcing and the ''OFF'' icon is displayed on the screen. No signals are sourced
between the terminals.
Notes:
Press the (START) key again to continue the auto-stepping and auto-sweeping mode after stopping them; The "RUN"
icon is displayed on the lower part of the screen.
The ability to use the (START) key to start mA auto-stepping and auto-sweeping mode is only available when the
source function is in the ON state.
〕key to display the auto-stepping mode signal "
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".The default source value will be shown.
" on the lower part
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