ABB 615 Series - Application; Measurement Modes

t s
k P
P
cal
[ ]
*
=
ref
GUID-FEA556F2-175E-4BDD-BD0F-52E9F5499CA8 V3 EN (Equation 43)
t[s]
operation time in seconds
k set value of Time multiplier
P
ref
set value of Reference power
P
cal
calculated residual power
GUID-D2ABEA2C-B0E3-4C60-8E70-404E7C62C5FC V1 EN
Figure 201: Operation time curves for wattmetric IDMT for S
ref
set at 0.15 xPn
4.2.6.6 Measurement modes
The function operates on three alternative measurement modes: "RMS", "DFT" and
"Peak-to-Peak". The measurement mode is selected with the Measurement mode setting.
4.2.6.7 Application
The wattmetric method is one of the commonly used directional methods for detecting the
ground faults especially in compensated networks. The protection uses the residual power
Section 4 1MAC059074-MB A
Protection functions
418 615 series ANSI
Technical Manual