Agilent Technologies E4371A Lawn Mower User Manual


 
Programming Overview - 5
65
Probe check
Probe check includes three separate functions: a continuity check, a power probe resistance check, and a
sense probe resistance check. All probe check functions require a cell to be connected to the channel
outputs.
The continuity check is a low-current stimulus test that should be performed prior to the power probe
test, or the sense probe test. Its primary function is to identify misaligned or bad probes. If the probes
pass this initial test, you can safely begin a test sequence and apply power to the cells. To perform the
probe continuity test use:
cfMeasProbeContinuity();
Probe resistance checks are internal procedures that use the plus and minus output terminals in
conjunction with the remote sense capability of the product to check that the resistance of both the power
and sense probes are within the allowable limits. When enabled, these checks occur continuously while a
sequence is running.
For the power probe resistance check, a user defined resistance limit must be specified. The power probe
resistance includes the probe, fixture wiring, and connection resistance. If the defined resistance limit is
ever exceeded on an individual channel, that channel fails and is removed from the forming sequence. To
specify the resistance limit and enable power probe checking, use:
cfSetOutputProbeTest();
For the sense probe resistance check, an internal measurement is made and compared against the
maximum allowable resistance that can be tolerated within the readback accuracy of the remote voltage
sense circuits. The maximum allowable resistance includes the probe, fixture wiring, connection
resistance, and an internal scanner resistance, which is typically 1000 ohms. If the maximum allowable
resistance is ever exceeded on an individual channel, that channel fails and is removed from the forming
sequence. To enable sense probe checking, use:
cfSetSenseProbeTest();
To measure the actual power probe resistance and sense probe resistance, use the following commands:
cfMeasOutputProbeResistance();
cfMeasSenseProbeResistance();