Some molded coils have black paint on the straight side and some do not, what is the difference?<\/p>\n
This subject is very important for users of large motors and generators. In machines with voltage higher than 6 kV, operating at the frequency of the electrical system (50 or 60 Hz), the coils (market standard) have a semi-conductive material (tape or paint) on the straight side in order to avoid partial discharges that deteriorate the insulating system. The fit between coil and slot is never perfect and we always have small voids in this contact. In this situation, we have electrically a circuit with 2 (two) capacitors connected in series of different dielectric constants (air and insulating).<\/p>\n
The semi-conductive material, applied over the insulator, aims to short-circuit the air capacitance and thus eliminate possible discharges. It is unlikely that machines with voltage below 6 kV will present the problem of discharges, taking into account that the working voltage applied to the insulator will be lower than 3.4 kV (phase x ground) and would not reach the disruptive voltage of the air.<\/p>\n
Contact our team and request an evaluation of your technical specification with the requirements of materials and manufacturing processes for coils and bars for motors and generators.<\/p>\n","protected":false},"excerpt":{"rendered":"
Some molded coils have black paint on the straight side […]<\/p>\n","protected":false},"author":1,"featured_media":1397,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_joinchat":[],"footnotes":""},"categories":[68,66,61,62],"tags":[],"class_list":["post-808","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-coils","category-corrective-maintenance","category-mca-3","category-mcag-3"],"yoast_head":"\n