Low Current Injector LCI 2058
The Low Current Injector (LCI) provides a reliable method for testing earthing/grounding systems, particularly those with low impedance (< 2 ohms) or which are extensive and where noise is present on the earthing system.
Portable earth testers are often unsuited to testing such earthing/grounding systems due to limited test current and inadequate noise rejection.
The LCI method injects a known current into the earth grid. The test current frequency is 58 Hz*. This provides a very unique test condition and the 58 Hz signal can be easily identified during the tests. Combined with the use of tuned voltmeters (58 Hz), the earth grid characteristics including impedance, touch, transferred, step voltages can be determined.
The LCI unit provides a constant current. This is necessary for accurate testing and overcomes the phenomena of current variation due to the time varying resistance of the remote test probes due to localised soil heating.
Auto shut-off is a safety feature that ensures the injected current immediately ceases should the injection circuit be interrupted.
The LCI output is galvanically isolated from the input supply.
In some cases it is impractical to use the LCI, for example where the injection is carried out using an existing power or transmission line running parallel to another line. In such cases the induced current in the test circuit may be excessive. However, a diesel genset can be used instead.
Specifications
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230 V AC 50/60 Hz (mains or genset) | |
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1 -10 A constant current | |
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auto-shutdown on open circuit | |
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58 Hz (50 Hz systems) | 52 Hz (60 Hz systems) |
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robust Pelican case | |
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17 kg |
* For 60 Hz systems LCI 2052 is available, and is tuned to 52 Hz ± 1 Hz
see also: Safe Engineering Services & Technologies for earth/ground modelling software
Finalist - IEE Innovation Awards 2005
download a brochure
download manual
download paper: practical testing of earthing/grounding systems
