ANSI/IEEE C57.13.1 §7.1 — …A 6 to 10 V lantern-type battery is connected momentarily to the secondary of the transformer under test and the momentary deßection of a milliammeter or millivoltmeter connected to the primary noted. If the positive terminal of the battery is connected to terminal X1 and the positive terminal of the milliammeter is connected to terminal H1, …the deflection will be upscale when the battery is connected and downscale when it is disconnected, if the polarity is in accordance with terminal markings.
Question to the previous posting: Please would you clarify how the following can work "" If the positive terminal of the battery is connected to terminal X1 and the positive terminal of the milliammeter is connected to terminal H1,..""
Well, I guess it means that if one uses a battery of known polarity to provide a {momentary} source of excitation to the transformer, a meter of known polarity will respond to the excitation.
In practical, the battery is connected to the primary of the CT and the meter to the secondary. The connections are as follows:
P1 to + of the battery
P2 to - of the battery
s1 to Red lead of meter
S2 to Black lead of the meter
Now by flicking the primary a positive deflection can be seen on meter.
