ABB REC670 Applications Manual page 426

Section 14
Control
420
DayHuntDetect: Setting of the number of tap changer operations required during
the last 24 hours (sliding window) to activate the signal DAYHUNT
HourHuntDetect: Setting of the number of tap changer operations required during
the last hour (sliding window) to activate the signal HOURHUNT
tWindowHunt: Setting of the time window for the window hunting function. This
function is activated when the number of contradictory commands to the tap
changer exceeds the specified number given by NoOpWindow within the time
tWindowHunt.
NoOpWindow: Setting of the number of contradictory tap changer operations
(RAISE, LOWER, RAISE, LOWER etc.) required during the time window
tWindowHunt to activate the signal HUNTING.
Power
P>: When the active power exceeds the value given by this setting, the output
PGTFWD will be activated after the time delay tPower. It shall be noticed that the
setting is given with sign, which effectively means that a negative value of P>
means an active power greater than a value in the reverse direction. This is shown
in figure 183 where a negative value of P> means pickup for all values to the right
of the setting. Reference is made to figure
direction of power through the transformer.
P>
en06000634_2_en.vsd
IEC06000634 V2 EN-US
Figure 183: Setting of a negative value for P>
P<: When the active power falls below the value given by this setting, the output
PLTREV will be activated after the time delay tPower. It shall be noticed that the
setting is given with sign, which effectively means that, for example a positive
value of P< means an active power less than a value in the forward direction. This
is shown in figure 184 where a positive value of P< means pickup for all values to
the left of the setting. Reference is made to figure
reverse direction of power through the transformer.
178 for definition of forward and reverse
P
178
1MRK 511 401-UEN A
for definition of forward and
Bay control REC670 2.2 IEC
Application manual