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Megger FT4 up to 4kV
- Ideal for testing Class 1 and Class 2 equipment
- Two ranges of test voltage
- Output control has safety zero interlock
- 'Breakdown', 'Trip Level' and 'Burn' modes of operation
- Audible and visual indication of breakdown and excessive leakage
current
The MEGGER FT4 Flash Tester operates from the mains supply and
provides a continuously variable a.c. test voltage up to a maximum of 4 kV. The
a.c. voltage frequency is that of the supply. A simple function switch permits
selection of one of the three modes of operation ‘Breakdown’, ‘Trip Level’
and ‘Burn’.
In the ‘Breakdown’ mode the instrument responds only to the
high frequency signals produced by the flashing arc of breakdown and trips the
test voltage only when this occurs. In the ‘Trip Level’ mode the output
voltage is tripped when the pre-set threshold level of leakage current is
exceeded or if breakdown occurs. For the ‘Burn’ mode of operation the output
is maintained irrespective of leakage current or breakdown; the output voltage
drops to limit the level of current flowing.
Leakage and breakdown failure are indicated by the illumination
of the fail lamp and the sounding of an internal buzzer. In the ‘Trip Level’
mode, the pre-set leakage current level is variable between 0,3 mA and 3 mA.
Leakage current in all modes is indicated on an analogue meter.
In the ‘Burn’ mode, neither the failure signals nor the
circuit tripping occurs, but the voltage drops to limit the current flowing
during burning at the fault. The ‘Burn’ mode is provided to enable the point
of breakdown failure to be located. As a safety feature, when the output voltage
is tripped due to a failure in the test item, an interlock system keeps the
voltage switched off until the circuit is manually re-set by turning the voltage
control to zero. The equipment is designed to BS and IEC safety standards.
Output sockets are provided for the two ranges and there is a
common earth terminal. An illuminated power supply switch indicates when the
instrument is connected to an energized supply and another lamp illuminates to
warn that the output test voltage is being applied. The instrument is robust and
built into a strong, portable, plastic case, with a cover
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