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The simple answer is NO.
Because the WL trip units are numeric and not analog, and because there is only one type of current sensor per frame size, the requirement that a calibrated secondary injection tester be used to "verify the curves" is no longer as meaningful as it once was. The curves in the WL trip units are not determined by the timing based on resistors and capacitors setting time constants but by comparing digitized waveforms, converted to RMS (when required) with tables stored in memory. If the trip unit powers up and measures and the CTs are continuous then to an extremely high degree of certainty, the device will perform according to it"s specifications.
The simple answer as to why the WLTS is not calibrated is that it is not a secondary injection test unit in the conventional sense. It does not "inject" a calibrated signal which is measured by the trip unit and then acted upon. It applies signals to the current inputs indirectly and instructs the ETU as to how they are to be interpreted. The trip unit then interprets the signals and times according to what it has been told that it is seeing. Actual analog signals are applied but they are scaled internally in a way which allows the trip unit to trip on different functions. All of this is necessary because the WL trip unit does not use conventional iron-core current sensors whose output signal is a current proportional to the current in the bus but rather air-core (Rogowsky) sensors whose output signal is a voltage proportional to the current flowing in the bus.
