Monitoring Devices (ETX type)
The ETX series are surge arrester monitoring systems which provide comprehensive information concerning the operational history and current condition of the surge arresters on the system. They designed to be installed in earth connection of any manufacturers surge arrester.
The ETX0 Surge Counter is equipped only with a 6 digit electro-mechanical cyclometer which counts each electrical surge carried to ground via the surge arrester.
The ETX3 Surge Monitor also include an active leakage current meter which indicating the level of leakage current instantaneously passing through the both internal active parts (ZnO Blocks) and surface of arrester housing. Significant changes after installation may indicate deterioration in the arrester or a buildup of surface contamination.
These instruments, which require no auxiliary power supply, are designed for installation in earth connection of single unit surge arrester, or alternatively the ETX0 may be used in the common earth connection of a three phase set.
Fully weatherproofed and sealed for life, they are housed in a one piece gravity die cast aluminum case and subsequently powder-coated for a high level of corrosion resistance. The glass viewing window is sealed in place with silicone rubber adhesive. A desiccator is enclosed to ensure any residual moisture trapped during sealing is absorbed for the service life of the counter.
The Surge Counters are easily mounted at the back of the case by means of an integral single-hole bracket paired with an M12x35 stainless steel bolt.
ETX Surge Counters require no maintenance apart from general cleaning of the viewing window and molded epoxy resin line terminal bushing for continued satisfactory operation.
- Counter: 6 digits (at least 6 counts/second)
- Meter Scale (for ETX3): 0-30 mA (peak/√2)
- Minimum count current: 250 A (8/20 µs)
- Maximum residual voltage at 10 kA (8/20 µs): 0.7 kV peak
- High current impulse withstand capability: 100 kA (4/10 kA)