tResetn: Reset time for step n if definite time delay is used, given in s. The default value
is 25 ms.
tnMin: Minimum operation time for inverse time characteristic for step n, given in s. When
using inverse time characteristic for the undervoltage function during very low voltages
can give a short operation time. This might lead to unselective tripping. By setting t1Min
longer than the operation time for other protections, such unselective tripping can be
avoided.
ResetTypeCrvn: This parameter for inverse time characteristic can be set to
Instantaneous, Frozen time, Linearly decreased. The default setting is Instantaneous.
tIResetn: Reset time for step n if inverse time delay is used, given in s. The default value
is 25 ms.
TDn: Time multiplier for inverse time characteristic. This parameter is used for
coordination between different inverse time delayed undervoltage protections.
ACrvn, BCrvn, CCrvn, DCrvn, PCrvn: Parameters to create a programmable under
voltage inverse time characteristic. Description of this can be found in the Technical
manual.
CrvSatn: Tuning parameter that is used to compensate for the undesired discontinuity
created when the denominator in the equation for the customer programmable curve is
equal to zero. For more information, see the Technical manual.
IntBlkSeln: This parameter can be set to Disabled, Block of trip, Block all. In case of a low
voltage the undervoltage function can be blocked. This function can be used to prevent
function when the protected object is switched off. If the parameter is set Block of trip or
Block all unwanted trip is prevented.
IntBlkStValn: Voltage level under which the blocking is activated set in % of VBase. This
setting must be lower than the setting Pickupn. As switch of shall be detected the setting
can be very low, that is, about 10%.
tBlkUVn: Time delay to block the undervoltage step n when the voltage level is below
IntBlkStValn, given in s. It is important that this delay is shorter than the trip time delay of
the undervoltage protection step.
10.2 Two step overvoltage protection OV2PTOV (59)
Section 10 1MRK 506 369-UUS -
Voltage protection
570 Line distance protection REL670 2.2 ANSI
Application manual