The only clear mention that 80 PLUS makes about the equipment it uses is in its FAQ, where the organization talks about a Yokogawa WT-2030 and Fluke 8846A 6½-digit multimeter. It also mentions a LISN device, though there's no reference to its make or model. The most important equipment is missing altogether, and by that we're talking about the (electronic) loads used for testing. We're surprised that 80 PLUS doesn't use an AC source to provide an input clear of any harmonics or noise to the PSU. Instead, it uses a plain UPS and an isolation transformer, which is essential for proper operation of the LISN.
In the diagram above, you can clearly see all of the equipment we have in our lab, the most important being the really expensive Chroma AC source that ensures stable and clean line input. In front of the AC source is an isolation transformer that uses its own dedicated power line. We also have a LISN device in our possession, though it's exclusively used by our EMI testing setup. The LISN device doesn't improve the accuracy of our efficiency readings; 80 PLUS claims it helps with PF accuracy under light loads.
The Yokogawa WT-2030 power analyzer 80 PLUS uses was considered high-end in its day. The company discontinued it back on 11/30/2010 though, and replaced it with the also-discontinued WT3000. We use a state-of-the-art N4L PPA1530 power analyzer featuring 0.05% accuracy and a UKAS ISO17025 calibration accreditation. All Newtons4th products, including our power analyzer, are designed and manufactured in the United Kingdom and are of extra high-quality. This company specializes in power analyzers, and our goal is to someday acquire a flagship PPA5500 offering an astonishing 0.01% basic accuracy!
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