Timer Characteristics; Application - ABB RELION REX640 Technical Manual

1MRS759142 C
4.5.2.6
4.5.2.7
REX640
Technical Manual
The Timer calculates the start duration value START_DUR, which indicates the
percentage ratio of the start situation and the set operation time. The value is available
in the Monitored data view.
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 input signal activation is
preselected with the global Blocking mode setting.
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.
The "Freeze timers" mode of blocking has no effect during the
"Inverse reset" mode.

Timer characteristics

The operating curve types supported by PHPTUV are:
Table 718: Supported IDMT operate curve types
Operating curve type
(5) ANSI Def. Time
(15) IEC Def. Time
(21) Inv. Curve A
(22) Inv. Curve B
(23) Programmable

Application

PHPTUV is applied to power system elements, such as generators, transformers,
motors and power lines, to detect low voltage conditions. Low voltage conditions are
caused by abnormal operation or a fault in the power system. PHPTUV can be used in
combination with overcurrent protections. PHPTUV is also used to initiate voltage
correction measures, such as insertion of shunt capacitor banks, to compensate for a
reactive load and thereby to increase the voltage.
PHPTUV can be used to disconnect from the network devices, such as electric motors,
which are damaged when subjected to service under low voltage conditions.
Section 4
Protection functions
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