Mains Underfrequency (Level 1 & 2) Ansi# 81U - Woodward easYgen-2000 Series User Manual

Configuration
Configure Monitoring > Mains > Mains Underfrequency (Leve...
4.4.2.4 Mains Underfrequency (Level 1 & 2) ANSI# 81U
General notes
ID Parameter
2900 Monitoring
2906
2904 Limit
2910
2905 Delay
2911
2901 Alarm class
2907
2902 Self acknowl‐
edge
140
There are two underfrequency alarm levels available in the control.
Both alarms are definite time alarms and are illustrated in the figure
below. The figure diagrams a frequency trend and the associated
pickup times and length of the alarms. Monitoring of the frequency
is performed in two steps.
Refer to
for the triggering characteristic of this monitoring function.
CL Setting range Description
[Default]
2 [On] Underfrequency monitoring is carried out according to the following parame‐
ters. Monitoring is performed at two levels.
Both values may be configured independent from each other (prerequisite:
Level 1 > Level 2).
Off Monitoring is disabled for limit 1 and/or Level 2 limit.
2 50.0 to 140.0 % The percentage values that are to be monitored for each threshold limit are
defined here.
2904: [99.6 %]
If this value is reached or fallen below for at least the delay time without inter‐
2910: [98.0 %]
ruption, the action specified by the alarm class is initiated.
Notes
This value refers to the System rated frequency (parameter
2 0.02 to 99.99 s If the monitored mains frequency value falls below the threshold value for the
delay time configured here, an alarm will be issued.
2905: [1.50 s]
2911: [0.06 s]
Notes
If the monitored mains frequency exceeds the threshold (plus the hysteresis)
again before the delay expires the time will be reset.
2 Class A/B/C/D/ Each limit may be assigned an independent alarm class that specifies what
E/F action should be taken when the limit is surpassed.
2901: [A]
2907: [B]
Notes
For additional information refer to
on page 587
2 [Yes] The control unit automatically clears the alarm if the fault condition is no
longer detected.
easYgen-2200/2500 | Genset Control
If this protective function is triggered, the display indi‐
cates "Mains underfreq. 1" or "Mains underfreq. 2" and
the logical command variable "07.08" or "07.09" will be
enabled.
Ä Chapter 9.1.1 "Triggering Characteristics" on page 481
The mains underfrequency Level 2 limit configuration
parameters are located below the mains decoupling
function menu on the display.
Ä Chapter 9.5.1 "Alarm Classes"
1750 Ä p. 94).
37535B