Industrial plants
Drive-heavy loads, harsh environments and power factor
Plant electrical rooms rarely look like the drawing. Drives generate harmonics the original design never accounted for, the environment is dirtier than the datasheet assumes, and the power factor penalty on the utility bill has been growing quietly for years.
What drives the specification
Variable frequency drives on both sides
Drives distort current upstream and stress insulation downstream. Input and output AC reactors to 1,000 V and 450 kW at 1–6% impedance address both ends, sine-wave filters to 690 V clean up long motor leads, and DC link reactors from 500 to 1,000 V DC smooth the bus. Where the plant's total harmonic contribution has to meet IEEE 519 at the point of common coupling, passive filtering is sized from the load list.
Environment the datasheet did not assume
Humidity, conductive dust and corrosive atmosphere shorten insulation life on open windings. Cast coil construction encapsulates the winding in epoxy under vacuum and gives a sealed surface that tolerates those conditions; VPI suits cleaner rooms at lower cost. Both are available across the 30 to 3,000 kVA dry-type line, open core and coil or in a ventilated NEMA enclosure.
Power factor and the utility bill
Low-voltage and medium-voltage power capacitors, with detuned and filter reactors for banks that would otherwise resonate with existing harmonics. Correcting power factor without first checking harmonic content is how capacitor banks fail early, which is why the load list matters more than the target kVAR figure.
Typical specification
- Plant distribution
- Dry-type, 30–3,000 kVA, cast coil or VPI
- Enclosure
- Open core and coil, or ventilated NEMA
- Harmonic rating
- K-factor K01–K30 for drive and IT load
- Drive-side filtering
- AC reactors to 450 kW, sine-wave filters to 690 V
- Power factor
- LV and MV capacitors, detuned and filter reactors
- Incoming service
- Padmount, 45–4,000 kVA, mineral oil or FR3
What to send us
Send the load list with drive ratings and the environment the unit will sit in. K-factor, enclosure rating and whether the capacitor bank needs detuning all follow from those two things.
Product lines for this application
Padmount Transformers
UL-listed, liquid-filled, 45-4,000 kVA
Dead-front, loop or radial feed, mineral oil or FR3-type fluid. UL file E526441, built to IEEE C57.12.00 / C57.12.28.
View the line →Dry-Type Transformers
UL 1561 / UL 1562, cast coil & VPI, 30-3,000 kVA
Indoor and enclosure-mounted dry-type units with UL-recognized insulation systems. Files E539752 (UL 1561) and E545481 (UL 1562).
View the line →Power Quality
Reactors, harmonic filters, capacitors, up to 35 kV
Line/load reactors, DC reactors, sine-wave and passive harmonic filters, LV/MV capacitors, and phase-shifting rectifier transformers.
View the line →Working on a industrial plants project?
Send the one-line and load list. Engineering review is part of every quote, and pricing comes back within one business day.