CHAPTER 2: CONVERTING SETTINGS FILES CONVERTING MIN II 67IG1 TO 350 32N
3 SERIES RETROFIT – INSTRUCTION MANUAL 31
2.5.2 Calculation of power pickup
To achieve the same operation zone with the 32N function, we need to calculate the
minimum power for the WGN 1 Power PKP setpoint.
1. Compute the average point between Voltage High (Vh) and Voltage Low (Vl) from the
MIN 67IG1 settings.
2. Compute the average point between Current High (Ih) and Current Low (Il) settings
from 67IG1
3. Compute the power corresponding to the middle point from the line between Vh/Il
and Vl/Ih points, as indicate din the figure below. Express the result in x CTxVT. This will
be the setting for WGN 1 Power PKP.
Example: (matching screenshots above)
Voltage average = (0.1 +0.3)/2 = 0.2 xVT
Current average = (0.025+0.01)/2 = 0.0175 xCT
Compute average power: 0.2 xVT * 0.0175 xCT = 0.0035 x CTxVT
Since the relay allows only three decimal places, select 0.003 xVTxCT as the more sensitive
setting. If a more conservative setting is required, select 0.004 xCTxVT
The 32N function operates if the computed neutral current is bigger than the Current PKP
level, the computed neutral voltage is bigger than the Voltage PKP level, the computed
power is bigger than the Power PKP level, and the direction of the power is detected in the
Forward direction.
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