Hioki IM3533 - Appendix6 the Residual Charge Protection Function

Appendix6 The Residual Charge Protection Function
A10
The instrument has been enhanced by the incorporation of a residual charge protection function. If by mistake
a charged capacitor is connected to the measurement terminals, this function protects the internal circuitry of
the instrument from discharge of such residual charge.
The maximum voltage from which the instrument can be protected by this function is determined from the
capacitance value of the sample under test by the following equation:
V: voltage (volts) (maximum 400 VDC)
C: capacitance (farads)
Appendix6 The Residual Charge Protection
Function
V
10
C
------
=
• The quoted maximum voltage from which the instrument can be protected by this func-
tion is for reference purposes only, and is not a guaranteed value. There may be danger
of damage to the instrument, depending upon the operational circumstances and upon
how often such charged capacitors are connected. In general, you should not rely upon
this protection function; be sure to discharge charged capacitors properly before con-
necting them to the test terminals.
• The residual charge protection function is for protection of the instrument against the dis-
charge of voltage present in charged capacitors, and is not capable of protecting the
instrument against DC voltage which is constantly applied such as a superimposed DC
voltage. If this is done, there is a danger of damage to the instrument.
See: Appendix5 Supplying DC Bias (p.A7)
Relationship of capacitance and residual voltage from which the LCR meter can be protected
Residual
voltage
Capacitance [F]