Johannesburg, South Africa — -ESI-AFRICA.COM — 11 November 2010 – Electro-technical company DEHN (UK) Limited “’ British-based specialists in lightning and surge protection safety equipment “’ have launched a new safety product in South Africa.
Revealing this in a release issued here, Surgetek “’ the company that represents DEHN in South Africa “’ said that the new PHV phase comparator was a two-pole device that offered safe and reliable operation while testing for in-phase conditions in three-phase electrical systems. It was suitable for rated voltages up to 36 kV/50 Hz, had SABS approval, and met the requirements of IEC 6148 standards. Phase comparators must be tested for correct operation before and after use, only by skilled personnel.
The statement added that the PHV phase comparator had distinctive red rings on both test prods that safely marked the end of the insulating sections in the direction of the operating head/indicator. It represented a visible limit of contact with live and earthed system parts, as well as the depth of penetration allowed into electrical systems. Type PHV was suitable for use in indoor and outdoor systems, but not in wet conditions.
It went on to explain that the eccentric mounting of the indication ensured good visibility from various angles, and provided for an out-of-phase condition when the phase angle between the two parts of the system to be tested was between 60° and 300°. A clear and sharp threshold was provided and the indication remained at a constant frequency over the testing range.
Used in contact with the parts to be tested, the PHV phase comparator was insensitive to magnetic and electrical interference. False indications were completely eliminated.
Surgetek explained that various colour coded test prods were available, and were selected for the desired voltage, and their simple bayonet connection ensured easy coupling to the basic test unit. The compact range of test prods was ideal for use in areas where space was limited, while standard test prods were suited for areas where larger span and separation was required. Test prods with a 90° degree angle were available for testing in switchgear where the axis of the bushing was mounted in a vertical plane.