An analog calibration issue exists for OptoEMU-SNR-3V units with date codes of July 2011 and earlier. This issue only affects customers who are using the product with a "direct connection," that is, measuring power via current transformers (CTs). The calibration issue does not affect those using the product with pulse inputs.
This zip file contains a command line utility and a technical note (in PDF format) showing you how to determine whether your unit is affected and how to fix the issue.
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