Manufacturing plant 480V upgrade and arc-flash program
Replaced aging switchgear and motor controls on a live process line, added VFDs with harmonic mitigation, and ran a full coordination and arc-flash program to drop incident energy to Category 2.
What we were engaged to build.
Actual ratings, devices and standards.
The service voltages, equipment ratings, protective functions and codes this project was built and tested against.
The specific electrical solutions we used.
How each design decision solved a real constraint on this project — from redundancy and coordination to protection and commissioning.
Fully rated 65kAIC overcurrent devices
Specifying fully rated (not series-rated) breakers means every device interrupts the available fault current on its own, removing the dependency on an upstream breaker that a series-rated scheme creates.
VFDs with line reactors and a harmonic trap
Line reactors at each drive plus a tuned passive filter hold current THD under 5%, keeping the utility within IEEE 519 and protecting the plant’s own sensitive controllers.
Coordination study that cut arc-flash to Cat 2
Adjusting instantaneous trip bands and adding zone-selective interlocking lowered incident energy at the MCCs from Cat 4 to Cat 2, so technicians work in lighter PPE.
Branch-circuit metering to SCADA
Every load panel reports current and power to the plant SCADA, so energy cost is allocated per line and a rising load trend flags a bearing or process fault early.
From the build.
Ready to scope your own project?
Request a consultation