Hioki BT5525, Instruction Manual, Page: 62 / 215

62
Detecting Micro Insulation Failure (BDD Function)
Enabling the BDD stop function
When the BDD stop function is enabled, the instrument will automatically stop testing when the
BDD count reaches or exceeds 1. Since the output voltage will also be stopped, this function helps
ensure testing safety.
Measurement-4
Charge period Steady period
Discharging
Test start Discharge start
Discharge complete
Test end
Test voltage
Resistance
measurement
BDD
EXT. I/O BDD
(Output)
Previous result
Cleared at start of test Output ON
when the BDD count is 1 or more
CCV CVV and CVI
ON
OFF
Measurement
delay
Measurement-1
N PLC M PLC
DELAY
MEAS
SPEED
BDD
Measurement-1
Saved to
memory
Saved to
memory
Saved to
memory
Saved to
memory
Measurement-2 Measurement-3 Measurement-4
Measurement-2 Measurement-3
BDD
Saved to memory
• When testing starts, resistance measurement starts in accordance with the sampling time setting
(1 PLC to 100 PLCs).
• When one measurement completes, the measured value is saved to memory.
• BDD events are detected in accordance with either the CCV settings (during the charging period)
or the CVV and CVI settings (during the steady-state period).
• If the BDD count reaches or exceeds 1, the output voltage will stop, and the instrument will enter
the discharge state. In addition, the EXT. I/O BDD output will turn on.
• In the above example, four measured values have been saved to memory, and one BDD
measured value has been saved to BDD memory, since the BDD stop function activated to end
testing during the fifth measurement.
HIOKI BT5525A961-00