Keithley 3720 User Manual page 106

Section 5: Basic Digital Multimeter (DMM) Operation
Calculated measurement open voltage
A calculated measurement, which exceed 120% of the range, will return an overflow reading.
dmm.opendetector open voltage
With dmm.opendetector = dmm.ON, a separate -1.5 A I
source, will pulse on and off before the start of each measurement while I
The A/D will monitor SHI for 2msec then switch to SLO for an additional 2msec. During either
phase, if the input voltage exceeds the above table, the A/D will abort in <100Psec and return an
overflow reading. If there are no open leads detected during the I
disabled and standard 4-wire is enabled.
V
MEAS
If Sense HI is disconnected, V
V
MEAS
For valid connections, INPUT Sense HI, V
amount of the voltage dip is the sum of I
measuring a 100k: on the 100k: range, the V
1.5PA) x 100K: during I
The tables below notes timing with dmm.opendetector = dmm.ON:
Range
1-10k:
100k:
1M:
10M:-
100M:
5-32
with open input:
with valid connections:
OPENLEAD
SHI and
SLO
IOPENLEAD
Phase
(msec)1
4.0
4.0
4.0
4.0
Series 3700 System Switch/Multimeter User's Manual
will droop less than -1V, causing an A/D overflow.
MEAS
, will dip during the 4msec I
MEAS
and the range I
OPENLEAD
MEAS
and 1V during measurement phase.
SHI
SHI
Measurement
Settle
Line
Time Time
Freq
(msec) (Hz) (msec)
min
0.5 60 0.0083
50 0.010
60 0.0083
2.0
50 0.010
60 0.0083
30.0
50 0.010
60
5.01 0.0083
Document Number: 3700S-900-01 Rev. A / August 2007
SHI and a separate SLO current
OPENLEAD
SOUR
phase, the I
OPENLEAD
OPENLEAD
and R
SOUR DUT
across the 100k: will be 0.85V (10 A -
max
250
240
250
240
250
240
250
remains enabled.
is
OPENLEAD
phase. The
load. For example, if