I am working on a project that has two large 480V/3P chillers that are starting across the line. The utility transformer is not large enough to handle the starting current of the chillers. When these chillers start, the 480V service experiences a voltage drop of 15-20%, depending on the other building loading. The facility was experiencing motor and control board failure that led to the discovery of the undervoltage condition. There also appears to be a controls issue with the chillers as some days they short-cycle and will have 40-80 starts, exacerbating the undervoltage problem.
A few days ago, the controls section of a vertical fan coil unit in the building started on fire. The fan coil unit is a 277V unit, fed from the service experiencing the undervoltage condition. I don?t think that the fire is related to the undervoltage problem that I am correcting, but that is outside my expertise. Has anyone ever seen or heard of an undervoltage condition causing a controls board to fail in such a way that it would start on fire?
A few days ago, the controls section of a vertical fan coil unit in the building started on fire. The fan coil unit is a 277V unit, fed from the service experiencing the undervoltage condition. I don?t think that the fire is related to the undervoltage problem that I am correcting, but that is outside my expertise. Has anyone ever seen or heard of an undervoltage condition causing a controls board to fail in such a way that it would start on fire?