ABB RELION REX640, Техническое руководство, Страница: 526 / 1960

The setting parameter
Minimum operate time defines the minimum desired
operation time for IDMT. The setting is applicable only when the IDMT curves are
used
The
Minimum operate time setting should be used with great care
because the operation time is according to the IDMT curve but always
at least the value of the
Minimum operate time setting. More information
can be found in
Chapter 11.2.1 IDMT curves for overcurrent protection
.
Timer calculates the start duration value START_DUR, which indicates the
percentage ratio of the start situation, and the set operating time, which can be
either according to DT or IDMT. The value is available in the monitored data view.
More information can be found in
Chapter 11 General function block features
.
Blocking logic
There are three operation modes in the blocking function. The operation modes
are controlled by the
BLOCK
input and the global setting in Configuration >
System > Blocking mode which selects the blocking mode. The
BLOCK
input can
be controlled by a binary input, a horizontal communication input or an internal
signal of the protection relay's program. The influence of the
BLOCK
signal activation
is preselected with the global setting
Blocking mode.
The
Blocking mode setting has three blocking methods. In the "Freeze timers"
mode, the operation timer is frozen to the prevailing value, but the
OPERATE
output
is not deactivated when blocking is activated. In the "Block all" mode, the whole
function is blocked and the timers are reset. In the Block OPERATE output mode, the
function operates normally but the
OPERATE
output is not activated.
4.2.6.6 Application
During an earth fault, HAEFPTOC calculates the maximum current for the current
feeder. The value is sent over an analog GOOSE to other protection relays of the
busbar in the substation. At the configuration level, all the values received over
the analog GOOSE are compared through the MAX function to find the maximum
value. The maximum value is sent back to HAEFPTOC as the
I_REF_RES
input.
The operation of HAEFPTOC is allowed in case
I_REF_RES
is lower than the locally
measured harmonics current. If
I_REF_RES
exceeds the locally measured harmonics
current, the operation of HAEFPTOC is blocked.
Figure 303: Protection scheme based on the analog GOOSE communication with three analog GOOSE
receivers
Protection functions 1MRS759142 F
526 REX640
Technical Manual