In today's world, pulses are common in electronic circuits. When these pulses encounter a resistor with high reactive components, they are distorted. If the resistor has high inductance, current through it will have a sluggish, slow rise time. The current will overshoot if the resistor has high capacitance. Either condition distorts the pulse's waveform, potentially disabling the circuit's function.
Wirewound resistor manufactures sometimes refer to Aryton-Perry windings when they talk about fast rise-time or high frequency response resistors. What are Aryton-perry windings? To make an Aryton-Peryy winding, you first wind a wire layer in one direction. After a layer of insulation, you wind the next wire layer in the opposite direction, with the turns crossing every 180 degrees. This reduces the undesirable reactance components of the winding: its inductance and capacitance.
The result? typical reactive values for these special designs are less than 1μh for a 500 ohm resistor, and less than 0.8pf capacitance for a 1 Megohm resistor. This provides a resistor with a fast rise-time of 20 nsec or less, while retaining the desirable tolerance, TCR and stability that are characteristic of wirewound resistors. So call us to get a quote on fast rise resistors.
RTDs or Resistance Temperature Detectors are widely used to measure temperatures in all kinds of industrial products. In many cases PT100 or PT1000 is specified. PT100 stands for 100 Ohm Platinum RTD, PT1000 stands for 1000 Ohm Platinum RTD.
Platinum, a precious metal, has seen dramatic price increases over the last 10 years. In 1999 platinum was about $400 per ounce, today it is $1700 per ounce and it peaked at $2200 per ounce in 2007. This has caused platinum RTDs to increase in price dramatically.
In the above example, our customer came to us to redesign their current part to make it more cost effective. We were able to shrink the part and integrate a threaded screw reducing part count and making it easier to install. A strain relief is built in for the flying lead which makes the overall package very robust.
We also transitioned from a platinum sensing element which has a TCR of 3850ppm/C to a low-cost, iron based wire which has a TCR of 3500ppm/C.
Riedon is the largest precision wirewound manufacturer in the world. We have the expertise to solve your most difficult problems.