Measuring Voltage With The Sense Terminals; Using Ratio With The Relative Function - Keithley 2010 User Manual

Measuring voltage with the SENSE terminals

The SENSE terminals can be used to measure DC voltage in the 100mV, 1V, and 10V ranges.
Assuming factory default conditions, make the connections as follows:
1. Connect test leads to the SENSE HI and LO terminals. Either the front or rear inputs can
be used; place the INPUTS button in the appropriate position.
2. Connect SENSE LO to LO. SENSE LO and LO cannot have a voltage difference of
greater than 5% of the lowest range selected.
3. Press DCV.
Press SHIFT then RATIO. Use the L, M,
4.
SENSEIN to ON. Note that the display will read VS for voltage on SENSE terminals.
5. Press AUTO to toggle autoranging. Notice the AUTO annunciator is displayed with
autoranging. If you want manual ranging, use RANGE L and M keys to select a
measurement range consistent with the expected voltages.
NOTE Only 100mV, 1V, and 10V ranges are available in either AUTO or manual ranging.
6. Connect test leads to the source.
CAUTION
7. Observe the display. If the "OVERFLOW" message is displayed, select a higher range
until an on-scale reading is displayed (or press AUTO for autoranging). Use the lowest
possible range for the best resolution.
8. Take readings from the display.

Using ratio with the relative function

The relative (rel) function is normally used to null offsets or to subtract a baseline reading
from present and future readings. (See "Relative" in Section 3 for complete details.) When
relative is used with the ratio mode, the instrument calculates the ratio reading as follows:
Measure Input
Ratio =
Sense Input
For example, assume the following:
Measure Input: 5V
Sense Input:
Rel Value:
The ratio value is:
Ratio = (5/2) – 1 = 1.5
Do not apply more than 350V peak to the SENSE terminals, or instrument
damage may occur.
– Measure Input Rel Value
2V
1V
Basic Measurements
, and keys to toggle RATIO to OFF and
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