Transformer Ratio TestVector Group and Polarity Exciting Current (Impedance) Test - No-Load Magnetization Test - Winding resistance - Tap Change Continuity and delta change - Tan Delta Bushings & windings - Zero Sequence Impedance Test – a subset of the Impedance re Tap-change - Dielectric Absorption & Polarization index - Mag Curves - Polarity, Ratio - Insulation Resistance Test - Mechanical interlocking on Transformer - SFRA - Oil Tests – Dielectric strength breakdown, DGA , Water Content, Acidity, Interfacial tension
4. What type of SWITCHGEAR Tests do you do?
Pressure Testing - Speed Testing and Travel Response Testing - Trip and Close Coil Testing - Busbar Current Capacity - Contact Resistance - Partial Discharge and Corona Testing - MV CTs - PD Levels - Indoor Switchgear Clearances - DC Battery Testing - CT Mag Curve Testing. Ratio/Polarity.
5. What type of MOTOR Tests do you do?
Winding Resistance - Overvoltage Pressure Test and Polarisation Index/Dielectric Absorption - Surge Testing - Tan delta Tests - Partial Discharge.
6. What standard should be used for CABLE /TRANSFORMER/RELAY/SWITCHGEAR/SUBSTATION testing?
HV Test prides itself in following guidelines recommended by SANS, IEC and ANSI standards. Or unless a client specifies ………
7. How often should an operating CABLE /TRANSFORMER/RELAY/SWITCHGEAR/SUBSTATION be tested?
HV Test recommends an annual test in line with annual plant shuts and maintenance. If the equipment has a long standing history of failure it is recommend to test every 6 months.