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PRC Facts

When your application demands the utmost precision wire wound electrical components, consider these factors to guide your decision on the right manufacturer for you:

Here's an interesting PRC Fact:

One of the wire wound precision shunt values we tested was a high precision value of ten milliOhms, a 10 watt part (PLV10AL 0.01 Ω ±1%) that developed over 30 amperes under full load. Because of its aluminum oxide rectangular case and special low TCR element, the resistance change under load was less than ±0.1% and there was virtually no measurable EMF, now that is a breakthrough! We certainly were impressed with the results and we are very confident that our premium wire wound components will outperform the competition and far exceed your expectations.

Importance of Greater Stability

The quality to resist permanent change must be designed into the resistor, sensor, or shunt right from the start. It is very difficult to stabilize or condition a general-purpose resistor, sensor, or shunt and be confident that it will meet a critical application. All of our components will adhere to published precision stability specifications... even if you specify 1% resistance tolerances. This is accomplished through the implementation of custom design elements, utilizing processes such as artificially aging components when deemed necessary among a handful of other techniques drawing from 75+ years of experience in the design & commercial manufacturing of custom precision wire wound resistors, wire wound sensors and wire wound shunts.

Tolerance, TCR and Temperature

These should all be considered as "one spec" when you require very accurate precision wire wound passive electrical components, the TCR characteristics and ambient operating temperature span are both vital factors that must always be considered as part of the equation to ensure compliance to the specific precision specifications your application calls for.

* Important Note:TCRs specified by PRC are calculated between the temp. range of +25 through +100° C.

Please check with us for expected TCRs outside of this range prior to placing an order.

Resistance Tolerance

Is expressed as a plus or minus percentage of the nominal ohmic value. The ohm is named after the German physicist Georg Simon Ohm who 1st discovered & documented its properties. The ohm is denoted by the symbol (Ω). All PRC's wire wound precision resistors are calibrated and tested within precision specified limits at +25 Degrees Celsius, unless it has otherwise been noted.


Since heat and cold are directly related to the TCR characteristics and the resistance tolerance in precision wire wound electrical components specifically, please be sure to specify the surrounding operational conditions that will be present during the use of all wire wound type precision resistors as well as any and all other high precision wire wound passive electrical components you might be utilizing in a precision application design.

Wattage Ratings

Full power ratings for all our wire wound resistor types are based upon standard (1%) resistance tolerances - at 25 degrees C. or to 125 degrees C., regardless of the resistor category selected. Derating is required for higher temperatures and closer tolerances, please refer to derating curves for each type of specific wire wound resistor. Sometimes a physically larger part or closer (to zero) TCR Characteristic will help, however heat is heat and must be carried off in some manner. Wire wound resistors are ideal for higher heat dissipation applications so if it is ultra precise resistance tolerances that your application calls for then precision resistor company is exactly the right choice to manufacture your precision wire wound passive electrical component.

TCR Characteristic

The temperature coefficient of resistance is the variation in resistance with respect to a change in temperature (ambient and/or self-generated). For precision wire wound resistors, sensors, & shunts, this change is expressed in parts per million (ppm), percent (%) or in Ω/ Ω per one degree Celsius and is calculated over the span of +25 to +100 Deg. C., using 25 & 100 as the standard reference points in the equation.

Reliability & Experience are integral attributes for a successful company

Whether you only need a few components for personal use or you are an engineer designing a major application for mass production that will be depended on by tens of thousands of end users, our premium product line of precision wire wound electrical components will perform exceptionally well for you. Our reputation is very important top us and we pride ourselves on our workmanship and adherence to promised delivery times. When you need a reliable experienced contract manufacturer you can count on, Precision Resistor is the clear choice made by thousands of engineers, year after year. Do not be fooled by our imitators who make empty promises they do not intend to keep, Go with PRECISION RESISTOR COMPANY, the brand already trusted by some of the worlds prominent companies, Let us demonstrate our widely successful production techniques and manufacturing capabilities that have kept our customers coming back since the company's inception way back in 1932.

Design your own precision wire wound resistor, sensor, or shunt

You can actually design, test and fine tune engineering samples selecting from any of our categories of precision wire wound electrical components so they perform to your custom specs, like a precision instrument should, whether you need a current sensing four terminal device or a simple voltage drop resistor. Try a few of our precision wire wound resistors, wire wound sensors, or wire wound shunts, many of the popular values are in our stock for immediate delivery, whether you need an axial lead (through-hole) or surface mounted design (SMT/SMD) type. Most axial lead parts do have a drop in surface mounted replacement. If we don't have what you need in stock, special engineering samples will be manufactured to your specifications quickly and at no cost to you.

Free Samples

Any of our precision wire wound passive electrical components will be provided free of charge for your testing purposes. If you are unsure whether our part is right for your particular application simply request a few samples to test and we will manufacturer them to fit your specs and ship them to you, within 7-10 working days for most jobs and at no cost to you. Don't worry, there is no commitment to buy so you have nothing to lose. Go ahead & send us your specs and you will be astonished just how well our high quality precision wire wound electrical components will perform to your precision specifications! All our parts are produced at our manufacturing plant located in beautiful Largo, Florida so you can trust you have a 100% American hand crafted part made right here in the good old United States of America, Contact us today, there is no job too big or too small for our dedicated & experienced team here at PRECISION RESISTOR CO. If you cannot find a standard part to fit all of the specifications, simply contact our sales department for immediate assistance. If your application calls for a precision wire wound resistor, sensor, or shunt, our experienced engineers can customize our design to provide you with the part designed specifically for your type of application. Call today and let us provide the custom high quality wire wound component your application is designed for so you can rest assured of your project's success!