Keithley 3700A Series, User Manual, Page: 49 / 74

Section 4: Applications Series 3700A System Switch/Multimeter User's Manual
4-8 3700AS-900-01 Rev. A / July 2011
Setting Detector
bandwidth
Freq band Aperture
time
Fixed no.
samples
per
reading
Auto
zero
Autodelay (ms) Measure
count
Total measure-
count time (s)
Average
Reading(s)
Off 2.35427 42.48
Once◄ 2.50335 39.95
FAST 300◄ 300 Hz-
300 KHz
16.67 ms
(20 ms)
1 On◄ 50
On
100
7.08160 14.12
Default setting ◄ at 50 Hz power line frequency
Example: Fast alternating scan, DC volts, and two-wire ohms
The following example illustrates how to configure a Series 3700A and a Model 3723 switch card for
fast alternating function scans. The example shows channel 1 mea7.5 VDC and channel 2
measuring a 1 K Ω resistor. Scanning, which includes a relay close, DMM configuration, DMM
measure, and channel open, is achieved at rates of less than 1.6 ms per channel.
Example program code for the Series 3700A
Code Notes and comments
loadscript test_func_chg
Name the script "test_func_chg"
reset()
Reset the Series 3700A to factory defaults.
channel.connectrule=channel.OFF
Set the connect rule off. The instrument closes
relays as efficiently as possible to improve speed
performance without applying a rule.
dmm.func="dcvolts"
dmm.range=10
dmm.nplc=0.0005
dmm.autozero=0
Set the DMM function to DC volts, with a range
of 10, NPLC of 0.0005 and autozero set to off.
dmm.configure.set("fastDCV")
DC volts DMM settings defined as "fastDCV".
dmm.func="twowireohms"
dmm.range=1000
dmm.nplc=0.0005
dmm.autozero=0
dmm.autodelay=dmm.OFF
Set the DMM function to 2-wire ohm
measurement with a range of 1000, NPLC of
0.0005, autozero of 0 and no autodelay.
dmm.configure.set("my-2w")
Save the 2-wire ohm DMM settings in a
configuration called "my-2w".
scan.measurecount=1
DMM takes one reading on each channel.
dmm.setconfig("4004", "fastDCV")
Use the "fastDCV" configuration for channel 4 on
slot 4.
dmm.setconfig("4024", "my-2w")
Use the "my-2w" configuration for channel 24 on
slot 4.
buf=dmm.makebuffer(20)
buf.clear()
buf.appendmode=1
Set the buffer size to 20 readings, clear the
buffer, and set the readings to be appended to
the existing buffer content.
scan.create("4004, 4024")
Scan list created with channels 4 and 24 on slot
4. Backplane channel 4911 and 4921 will be
automatically paired.
scan.scancount=10
Set the scan to loop 10 times.