Areva MiCOM P921 - Page 170

P92x/EN FT/E11 Technical Guide
User Guide
Page 92/110 MiCOM P921-P922-P923
- Additional alarms for the MiCOM P923 :
Alarm Significance
df/dt1 1
st
stage of the rate of change of frequency information
df/dt2 2
nd
stage of the rate of change of frequency information
df/dt3 3
rd
stage of the rate of change of frequency information
df/dt4 4
th
stage of the rate of change of frequency information
df/dt5 5
th
stage of the rate of change of frequency information
df/dt6 6
th
stage of the rate of change of frequency information
EQUATION C time delayed result of the "C" logic equation
EQUATION D time delayed result of the "D" logic equation
13.1.2 "Relay" ALARMS
Any software or hardware fault of the MiCOM relay generates an
“hardware/software” alarm.
If an hardware error appears, the following prompt will appear :
HARDWARE ALARMS
If the 1 key is pressed, the significance of the hardware problem is then indicated :
for example,
RAM ERROR 1/1
The “Warning” LED will blink. The reset of these alarms is not possible. Only the
disappear of their cause will lead to their reset.