IEC Equipment Voltages
There are two (2) voltage levels used in IEC, low voltage ( < 1000 V ) and high voltage ( > 1000 V ). Medium voltage, inspite being oftenly used …
Resistance of Earth Electrodes in Parallel
In previous articles Single Earth Electrode and Earthing Resistance Calculation, I have presented methods of calculating the earth resistance using IEEE or IEC methods. AS 1768 Appendix C recommends that …
Resistance of a Single Earth Electrode
The resistance of a single earth can be calculated if the soil resistivity is known. An earth rod driven vertically, the electrode resistance can be calculated using the following formula. …
Isolation of Neutral Conductor in Hazardous Areas
IEC 60079-14 (2007) Clause 8.2 Electrical isolation, states that: To allow work to be carried out safely, suitable means of isolation (for example isolators, fuses and links) shall be provided …
Philippine Electrical Code – Working Spaces
Working space generally applies to the protection of the worker. Dedicated equipment space applies to the space reserved for future access to electrical equipment and to the protection of the …