I had a similar problem with a Yokogawa WT-500 a few year ago... Maybe this will help you
Also I happen to be working with a WT-1804E myself at the moment, but I am interfacing through VX11 (Ethernet).
But I have ran into another little problem, the WT-1800E LabVIEW drivers do NOT support frequency measurement
It's not a show stopper, but it really makes me wonder about their LabVIEW support when they forget a common AC measurement like frequency and Yokogawa tech support knows NOTHING about LabVIEW.
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=== Engineer Ambiguously ===
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