ABB Relion REQ650, Applications Manual

Page: 271 / 340

Limits are directly set in applicable measuring unit, V, A , and so on,
for all measureing functions, except CVMMXN where limits are set
in % of the base quantity.
XHiHiLim : High-high limit.
XHiLim : High limit.
XLowLim : Low limit.
XLowLowLim : Low-low limit.
XLimHyst : Hysteresis value in % of range and is common for all limits.
All phase angles are presented in relation to defined reference channel. The parameter
PhaseAngleRef defines the reference.
Calibration curves
It is possible to calibrate the functions (CVMMXN, CMMXU, VNMMXU and
VMMXU) to get class 0.5 presentations of currents, voltages and powers. This is
accomplished by amplitude and angle compensation at 5, 30 and 100% of rated
current and voltage. The compensation curve will have the characteristic for
amplitude and angle compensation of currents as shown in figure
104 (example). The
first phase will be used as reference channel and compared with the curve for
calculation of factors. The factors will then be used for all related channels.
1MRK 505 291-UEN A
Section 12
Monitoring
265
Application manual