Defective earth testing for an electric fence energizer
US5771147A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1996 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Aug 22, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05C3/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In an electric fence energizer there is an exterior earth connection such as an earth connection post (16). The electric fence energizer comprises in the conventional way a transformer (T) having a primary winding (L.sub.1) and a secondary winding (L.sub.2), one exterior terminal (9) of which is connected to the conductor (17) in the electric fence and the other exterior terminal (11) is connected to the earth connection, high voltage pulses being induced over the secondary winding (L.sub.2) when voltage pulses are applied over the primary winding (L.sub.1). For a determination of the quality of the earth connection, the voltage over a small part of the secondary winding (L.sub.2) is obtained capacitively by means of an extra winding (L.sub.3) in the transformer (T). For an evaluation of this voltage, it is connected, only for a determined polarity, to a charging circuit for a capacitor (C.sub.2), which is discharged over a known resistor (R.sub.2, R.sub.3). The voltage (V.sub.21) over this capacitor (C.sub.2) is processed for a determination of the quality of the connection to earth. Then the time difference can be determined between the time (t.sub.0) when the induction high volt…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.