KPC105x - EARTH CURRENT GUARD FOR SYSTEMS WITH GROUNDED NEUTRAL
- Grounded neutral earth current Protection
- Definite Time Trip Delay
- Two individually setable alarm relays
- For use with 1A or 5A current transformers
- Non-resitive earth current offset function
- Very fast analogue output (<50mS), (F-version)
Description
KPC105x monitors leakage current in a grounded neutral network and provides earth current protection.
True RMS measurement not affected by heavily distorted waveforms (1.0%) protection. Less than 50mS current detection time. R1 energises when trip level one (Warning) is exceeded and R2 trips when trip level two (Alarm) is exceeded. R3 is an extra status relay that energises if either alarm relay 1 or 2 is active and can be used for local indication, PMS input, alarm system input etc.
Fast response mA output signal proportional to a range (KPC105F).
Safety
The instrument measuring input is overload protected against high current <15xCT(/1A) or <3xCT(/5A). If unit is used for tripping it is recommended to use manuel reset.
User settable trip levels and delays. Colour of LEDs indicates alarm status. LEDs flash during countdown.
Offset Function
Only the resistive (ohmic) earth leakage current is a measure for the insulation condition between the AC supply and its protective earth. Any reading of leakage current in a fault free network will be caused by the networks spread capacitance. An offset potentiometer on the rear allows normal reactive (capacitive) currents to be ignored.
Protective Earth (PE) Grounding
The neutral grounding point is monitored by a Current Transformer (preferable class 0,5 or better). The ground connection can be directly or trough a neutral earth resistor to reduce the maximum earth current in the network.
Any leakage to earth on the LOAD side will be seen as an imbalance situation, and will cause the Earth Current Guard to trip if leakage current exceeds the trip level settings.
The unit meets EN 61010-1 Cat. III, Pollution degree 2 and the relevant environmental and EMC tests specified in EN 61326-2-4 to comply with the requirements of the major Classification Societies.
