Model 6517B Electrometer Reference Manual
Section 5: Measurement options
6517B-901-01 Rev. C / August 2015
5-5
Selecting voltage source range
The voltage source range cannot be changed while in Auto V-source Ohms. With the voltage source
value displayed, the position of the decimal point denotes the currently selected range. For example,
a reading of 000.000 V is 0 V on the 100 V range, while a reading of 0000.00 V is 0 V on the 1000 V
range. The
RANGE
option of the
CONFIG V-SOURCE
menu is used to change the V-source range
and is summarized in the table in
VSource configuration
(on page 5-2).
1. From
the
CONFIG V-SOURCE
menu, select
RANGE
to display the range options (±100 V or
±1000 V). Note that the 100 V range provides better resolution; 5 mV vs. 50 mV for the 1000 V
range.
2. Place the cursor on the desired range and press
ENTER
.
3. Use
the
EXIT
key to back out of the menu structure.
Adjusting voltage source value
The voltage source value cannot be changed while in Auto V-source Ohms. The voltage source value
can be changed while in operate. While in operate, the output voltage immediately updates to reflect
the displayed value.
1. Select the voltage source edit mode by pressing the up, down, left, or right arrow key. The EDIT
annunciator turns on and the cursor position for the voltage source value is denoted by the
flashing digit. Note that the voltage source edit mode will be cancelled if no edit operations are
performed within any three second period.
2. Using the keys, place the cursor on the digit to be changed and use the up or down key to
increment or decrement the value.
3. Polarity changes can be made in two ways:
Increment or decrement the reading past 0 V to change polarity.
Place the cursor on the polarity sign (+ or -) and press up or down to toggle polarity.
4. When finished, the voltage source edit mode cancels (EDIT annunciator off) after three seconds.
Voltage and current limit
The V-source has a 1 mA current limit for the 1000 V range, a 10 mA limit for the 100 V range, and an
adjustable voltage limit. If the current limit is reached, the VOLTAGE SOURCE OPERATE indicator
flashes. While in current limit, the programmed voltage value is not being sourced. For example,
assume the voltage source is programmed to source 200 V to a 100 k
load. In this situation, current
limit occurs at approximately 100 V (100 k
1 mA = 100 V). Thus, the voltage source only outputs
100 V.
A resistive current limit is also available for the V-source. When selected, a 20 M
resistor is placed
in series with the V-source HI lead. This allows current to be limited. For example, with a programmed
voltage of 100 V, current is limited to 5 µA (100 V / 20 M
= 5 µA).