ION9000T HSTC Alarm Settings with a PT

[sesa28787_bridg]

I'm trying to determine an appropriate Magnitude Threshold Vrms setting for the HSTC alarm. The meter is wired as a 4W-Wye with 4200:120V PTs. Per the ION9000T user manual, Potential transformer (PT) scaling is not applied in high-speed transient capture. High-speed transient measurements are performed on voltage levels present at the meter’s voltage terminals.

[Charles_Murison]

Hello @sesa28787_bridg ,

I am not sure I understand the confusion. The HSTC capture is triggered based on the voltage levels as seen at the meter's voltage terminals. You would define the secondary values you would want HSTC captures to trigger on.

Regards,

Charles

[DanL · Accepted solution]

in this scenario with 4200:120V PTs, in order to trigger captures on transients on the system exceeding +/-42kV, (assuming you are using good, high bandwidth, wide dynamic range PTs that don't attenuate transients) you would configure the ION9000T's HSTC threshold to 1200 V.

[sesa28787_bridg]

Thank you for your response. Determining the quality of the PT  was my next thing I was going to ask. The ION9000T meter is mounted in Square D Metal- Clad switchgear. So, I can only assume it is proper for HSTC. As you have mentioned (assuming you are using good, high bandwidth, wide dynamic range PTs that don't attenuate transients). I attached the cut-sheet of the PT supplied. Any thoughts??