Testing of contactors under voltage sag and non-sinusoidal voltage conditions

Sensitivity of electromagnetic contactors for voltage sags and non-sinusoidal voltage supply has been carried out by laboratory testing. Effects of sag characteristics such as; sag magnitude, sag duration and point on wave of sag initiation to be considered on contactors behavior. Contactors are subjected to voltage sags of depth varying, sag duration varying 5 ms to 600 ms, different point on wave and under different non-sinusoidal conditions. A Schaffner Profline 2100 EMC has been used as sag generator to create sag characteristics. The results show that sensitivity curves of the contactors depend on sag magnitude, sag duration and point on wave, whereas influence of non-sinusoidal voltage is slightly different.