There are various types of power resistors:

  • Wirewound resistors
  • Grid resistor
  • Water resistors

Express Transformers & Controls Ltd. offer power resistors in 130, 200, 300, 400, 450, 600, and 750 watt.

Types of Power Resistors

Wirewound resistors

Wirewound resistors are constructed when a metal wire is wound around a solid form. The end of the winding has metal caps attached with metallic leads. Enamel is often coated on to the end product. This is to protect it from the environment and ware and tear. Many resistors are built to endure temperatures of up to 450 °C.

Grid resistor

Large metal strips between two electrodes is known as a grid resistor. Their sizes can very, but some grid resistors are as large as a refrigerator. Often times, grid resistors can endure currents of over 500 amperes. They are used as brake resistors and load banks for railroad vehicles, neutral grounding resistors, load testing of generators and harmonic filtering for electric substations.

Water resistors

Water resistors are consisted of tubes filled with a saline solution with an electrode at both ends. The concentration of salt in the solution controls the resistance of the resistor. Water in the tube provides a large heat capacity which allows high power dissipation. Some high power water resistors use in pulsed modes utilize copper sulfate solutions instead of saline.

Where To Buy?

Click here to see our range of wirewound resistors. Express Transformers and Controls Ltd are a trustworthy transformer manufacturer that offers you quality products with support at the price you can afford. Reap the benefits of quality transformers from us today!


Furthermore, you can check out examples of our work by visiting our gallery.

Please feel free to contact us to discuss your design requirements. Our lead engineer details are listed below and they are very happy to discuss your particular project needs with you.