GENERAL PURPOSE ISOLATION TRANSFORMER
General Purpose Isolation transformers are used to lower distribution voltages (480 or 600V) to lower voltages (typically 120/240 or 208Y/120) for power distribution within commercial or industrial buildings. These “two windings” transformers provide the electrical isolation required, and allow for short runs of high current, low voltage cables, reducing losses in the system, and reducing costs.
General Purpose Isolation transformer are suitable for supplying the following type of loads:
General purpose lighting & electrical
Motors (without VFD controllers)
Resistive Heating
Industry Standards:
CSA certified
UL listed
Product Specification
Specification
Q.T.S Standard
Available Options
Capacity
Voltage Class
Conductor
N/A
Cooling
Insulation System
C - Copper or A - Aluminum
Frequency
Self cooled (ANN)
ANC (Non ventilated units)
60 Hz
50/60 Hz
Class 220 (220 ⁰C at hottest spot, 150 ⁰C average rise)
No K-Factor
Temperature Rise
K Factor Rating
150 ⁰C average rise
115 ⁰C, 80 ⁰C
N/A
Impregnation
Efficiency level
Terminations
Polyester Resin Dipped and Baked
3 to 333kVA Single Phase and 5 to 1,000kVA Three Phase
Taps
Typically +/-2 x 2.5%, +/-1 x 5%
Other primary or secondary tap available
Lugs or pads
NRCan 2019
DOE 2016
Smaller kVA’s are classified as control transformers. Larger kVA’s are classified as power transformers.
Impedance
Per CSA C9
Enclosure Type
Seismic
1.2 kV (CSA), 600 V (UL)
Sound Level
NEMA Type 1 or 3R indoor
Type 1, 2, 3R, 4, 4X or 12 Enclosure
Shipping
Lead Time
3 to 6 Weeks Typical
Expedited available
Per CSA C9 and NEMA ST-20
N/A
Available K4, K9, K13, K20
Epoxy dipped and Baked
Other custom specifications available
Higher levels available
3 dB below CSA level
Canada Zone 6, USA Zone 4
Specific seismic requirement available
Bolted to skid, with nylon cover
Specific Cu-Al lugs available.
Special impedance available
Shrink wrap, special skid, export crating