Speed - Keithley 2002 Getting Started Manual

2-14 Measurement Options

Speed

SPEED sets the integration time of the A/D converter, the period of time the input signal is
measured. The SPEED can be set for each measurement function except FREQ. The integration
time is specified in parameters based on a number of power line cycles (NPLC), where one PLC
for 60Hz is 16.67msec and one PLC for 50Hz and 400Hz is 20msec.
In general, the fastest integration time (0.01 PLC) results in increased reading noise and less
usable resolution, while the slowest integration time (50 PLC) provides the best common-mode
and normal-mode rejection. In between settings are a compromise between speed and noise.
Configuring speed
Each measurement function, except FREQ, can have its own unique integration time. Speed
is set from the configure function menu structures. The procedure is summarized as follows:
1.
2.
3.
NOTE
Press the CONFIG key and then the desired function key (DCV, ACV, etc.).
Using the cursor keys (
lowing speed options:
NORMAL: Sets the integration time to 1 PLC.
FAST: Sets the integration time to 0.01 PLC.
MEDIUM: Sets the integration time to 0.1 PLC.
HIACCURACY: Sets the integration time to 50 PLC.
SET-SPEED-EXACTLY: This options prompts you to enter a PLC value (0.01 to 50).
SET-BY-RESOLUTION: Automatically optimizes the integration time for the present
resolution setting (see the User's Manual).
Use the menu items to configure speed. A menu item is selected by placing the cursor
(using and keys) on it and pressing ENTER. Parameter values are changed using
the cursor keys and the RANGE keys, and then pressing ENTER. See MENUS if you
need more information to navigate through the menu structure.
For more information, see SPEED in Section 2 of the User's Manual.
and ), select SPEED and press ENTER to display the fol-