6 PASSIVE BRIDGE
6.1 Principles of Operation
In PASSIVE BRIDGE mode KMK 8 applies the classic Wheatstone
bridge arrangement consisting of fix and variable resistors, generator and
null-indicator.
• The generator produces 100 V DC or 100 Vp, 11 Hz AC
• The null-indicator contains a 11 Hz low pass filter
• The variable resistor is a high precision potentiometer (Helipot)
The passive bridge of KMK 8 can be manually balanced by means of the
Helipot (like it is usual at the conventional bridges), but the reading of
potentiometer resistance is electronic.
That solution combines the good features of conventional bridges with
the comfort of micro processor controlled circuits.
• The passive bridge measures accurately even in the presence of
AC interference voltages.
• The electronic „reading“ of potentiometer provides quick and
accurate calculation of fault location (Lx/L)
Applications
DC Fault Location
• Fault location with Murray-Method
• Fault location with 3 Point-Method
• Fault location with Küpfmüller-Method
• Resistance difference measurement
AC Fault Location
• Fault location with Küpfmüller-Method
• Capacitance balance measurement
KMK 8 applies the generator and the null-indicator also for resistance
measurements like
• Loop resistance measurement
• Insulation resistance measurement
To Next Page
