There are 3 versions of ATE-30 device. All are currently available.
Dave Kornegay was the engineer at Woodward Governor Company who designed the original PT Interface 25 years ago. The attached YouTube video introduces a new, improved version of this hydroelectric turbine speed sensing device. 
In 2002, L&S Electric ordered the same PT Interface contract manufacture from ATECo to Dave's original specification. Design performance certified to IEC's highest standards for discriminating customers.
ATE-30 was the first version, still available by special order today.
ATE-31 was an upgrade to meet UL standards with improvements guided by "lessons learned" from the ATE-30 project.
ATE-32 Upgades again to meet the highest IEC standards for a customer.
Addition of a hysteresis circuit on the input to the isolaton amplfier blocks signals with amplitude less than (+/-) 0.15V. This threshold voltage is adjustable from 0.02 to 1.0V p-p on request.
The subject governors in the video were upgraded to digital PLC control systems a year ago, but did not replace the 110 VAC voltage wires from the PTs with instrumentation grade shielded, twisted pair wire, which caused the problem described in the video. The original purpose of these wires did not include instrumentation connections of low-voltage signals, so unshielded wire was OK in the original installation many years earlier. When the PT Interface input is added to the circuit, the wires changed from "power wiring" to "instrumentaiton signal wiring" and should be changed to instrumentation wire. Crosstalk in the unshileded wiring  was measured at 0.14VAC when the other unit was on-line. Threshold voltage of the PT Interface was reset to 0.16VAC.  Specification is 0.2 to 180 VAC, with a noise floor at 0.15V. 
Click here: Hydroelectric Speed Sensing With PT Interface - YouTube
Dozens of ATE-32 modules have been installed to date.

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