Riedon Precision Wirewound - Mexico vs USA - Page 1
Forum section: electronics / general

author: Nogtail
author_rank: Regular Contributor
timestamp: June 25, 2024, 07:35:49 am
content: I've bought quite a few of Riedon's precision wirewound resistors over the past few years - mostly their SM-15 and 101 series with 0.01% tolerance. Until now they've all been manufactured in USA, have been clearly marked and measure bang on their nominal value.Unfortunately my latest order hasn't lived up to the previous ones. The printed markings are practically unreadable and they measure way off the specified value. The measured resistance seems to jump all over the place - even when the temperature is controlled within ~1°C. As far as I know these the first ones I've had that have been made in Mexico - not sure whether or not this is correlated.I bought the resistors from Digikey so I don't think they're fakes. My multimeters (2x Keithley 2000) don't have a current calibration, so it's possible they're the ones drifting, however, they both agree to the last digit so it's unlikely they're both drifting the same amount. They'd also have to have a linearity issue as one of the resistors reads around +0.02% and the other reads around -0.01%.Has anyone else had problems with Riedon's precision wirewound resistors? I'd be particularly interested to know if there's a quality difference between the USA and Mexican made ones.Here's some photos of the USA manufactured ones:And the Mexican ones:Yeah, I know it's probably not a great idea to bend the leads this much, but it didn't seem to make much of a difference to the reading.

author: Edwin G. Pettis
author_rank: Frequent Contributor
timestamp: June 26, 2024, 01:33:38 am
content: According to what I've read, Riedon was sold awhile back but I don't know who to as yet. I had visited the California plant some years back as a consultant when it was still owned by the original people but I believe they decided to retire and sold it. Whether or not the resistors were made in the US or Mexico, they should still conform to stated tolerances and other parameters. If they are indeed out of tolerance, I would contact Digi-key and let them know about it. I also agree, it is not a good practice to bend the leads that close to the body.

author: floobydust
author_rank: Super Contributor
timestamp: June 26, 2024, 01:51:44 am
content: April 17, 2023 Bourns Acquires Assets of Riedon, Inc. "...including Riedon's {primary} manufacturing operations in Alhambra, California and in Tecate, Mexico..."source

author: Nogtail
author_rank: Regular Contributor
timestamp: June 26, 2024, 02:15:02 am
content: I'd imagine Bourns are trying to find areas where they can cut costs. Riedon just made a post about moving their manufacturing operations to Mexico to "enhance production capabilities without compromising the quality and variety of the products you rely on":https://riedon.com/blog/transition-of-former-riedon-manufacturing-operations-for-precision-resistors-to-tecate-mexico/Perhaps they're having some teething issues while moving the production? Whatever the cause, I'm certainly not impressed with the quality so far.I'm not sure if I've got good enough evidence to report to DigiKey. I'm pretty confident it's not my instruments causing the error, but I haven't got the calibration to prove it.

author: guenthert
author_rank: Frequent Contributor
timestamp: June 26, 2024, 07:40:58 am
content: Quote from: Nogtail on June 26, 2024, 02:15:02 amYou can show the difference between the US and Mexico made ones. For that calibration isn't needed.