Hioki RM3542 - 4.11 Maintaining Measurement Precision (Self-Calibration); 4.12 Compensating for Thermal EMF Offset (Offset Voltage Compensation - OVC)

4.8 Test for Short-Circuited Probe (Probe Short-Circuit Detection Function)
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4
Four-terminal measurements are not possible when a conductive for-
eign object is present between the POT and CUR probe tips. To
detect short-circuited probes, this function measures the resistance
between the CUR and POT terminals after a specific time (initially 5
ms) following the end of measurement. Probe short-circuit detection
is disabled by default.
When a probe short-circuit is detected, an error message appears on
the measurement screen, and the
PRB_SHORT and ERR signals are
output. (
ERR:021 Probe short error)
Short-circuit detection can also be controlled by asserting the active-low PRB_CHECK EXT I/O signal.
Asserting the PRB_CHECK
signal while measuring causes short-circuit detection to be performed after the
end of measurement (p. 85).
About Probe Short-Circuit Detection
• If probes are connected to the DUT during probe short-circuit detection, the short circuit is detected. Ensure
that the probes have sufficient time to separate from the measurement object.
• Probe short-circuit detection occurs within about 1 ms.
• The threshold for probe short-circuit detection is fixed at 500, so if the resistance between CUR and POT
probes is larger, detection is not possible.
4.8 Test for Short-Circuited Probe
(Probe Short-Circuit Detection Function)
Foreign Object
POT
CUR
DUT Electrode
DUT
Timing Chart
(Probe Short-Circuit Detection)
Probe short-circuit
PRB_SHORT
Comparator
Hi, IN, Lo
End of Measurement
EOM
Measurement
Start
TRIG
Contact
Transport
Measurement
stage
Available
Short-Circuit
Detection
Transport
DUT1 contact
DUT2 contactTransport
Probe short-circuit
DUT1
measurement
DUT2
measurement
Short-Circuit
No Decision
Detection timing setting
• Even while the probe short-circuit detection function is set to be disabled, short-circuit detection is performed when the
EXT I/O PRB_CHECK signal is asserted.
• When the internal trigger [TRG: INT] source is selected, short-circuit detection is not performed after the end of mea-
surement. However, short-circuit detection can still be executed by asserting the PRB_CHECK
signal.