• 1201 West Randolph St., McLeansboro, IL, USA

STC, Inc. - Social Media

At this time, our manufacturing capacity does not allow us to build transformers larger than about 10 KVA.

In North America, standard outlet power runs from 110 to 120 volts at 60 Hz. However, the input voltage or frequency may vary, depending on the circuitry feeding into the unit. We can build transformers for virtually any voltage and frequencies. Refer to the Worldwide Voltage & Frequency Standards for information about other national voltage and frequencies.

Yes. In many cases, customers will send us non-functional transformers to break down, and this is the most accurate way to determine the specifications. Schematics of the device can be helpful, but most cases require our physical study of the transformer. Please contact us to discuss your options.

Yes! In fact, the majority of transformers we sell are built according to custom specifications. Feel free to email or call to discuss your requirements.

Yes! Please refer to our LPC-style transformers for a list of our standard UL-approved products. Transformers built to custom specifications can be UL approved for an additional fee. Please contact us for details.

Yes! We can build both surface-mount and through-hole transformers for use on printed circuit boards. We can also provide all phases of electronics manufacturing services. Refer to our STC Electronics website for more information.

We test 100% of our products according to your specifications. The type of testing we can perform may depend on the type of transformer as well as your specifications. The scope of our testing capabilities includes (but is not limited to):

  • Continuity
  • Magnetic Current (AKA Exciting Current)
  • Winding Inductance
  • Leakage Inductance
  • Winding Resistance
  • Open Circuit Voltage
  • Loaded Circuit Voltage
  • Turns Ratio
  • Dialectric Testing (AKA HiPot or High Potential Difference)
  • Quality Factor
  • Interwinding Capacitance
  • Insulation Resistance

We most often use FedEx, and UPS for both freight and smaller shipments, though we can ship through other companies according to customer preference.

Yes! Our transformers can be built in accordance with the RoHS Directive upon customer request.

Yes. Send us your electrical requirements and required dimensions. We can usually provide an accurate estimate of the physical dimensions needed to meet your electrical specifications.

If the transformer was designed for use in North America (where the current is 60 Hz), it will likely need to be redesigned. For use in Europe, the transformer will need to be redesigned for a 50 Hz frequency, which generally increases the size by about 20%. Without a redesign, a 60 Hz transformer will run at a higher temperature to achieve the lower frequency. Refer to the Worldwide Voltage & Frequency Standards for more information.