RECLOSER CONTROL EVRC2A-N6,NT
http://www.entecene.co.kr
128
EN
HANCED
TEC
HNOLOGY
7.2. Phase (Fast/Delay) Time Overcurrents (51P)
The EVRC2A has two phase time overcurrent elements. The phase time overcurrent element
contained in the EVR2A, is set based on CT secondary current as connected to the current inputs.
The phase time overcurrent element is the most commonly used as a protective element for
distribution systems and also used in both down-line and back-up recloser protection. The phase
time overcurrent element provides a time delay versus current for tripping that is used for an
inverse time curve characteristic coordinated with current pickup value, curve type, time dial,
time adder, minimum response time setting and reset type. This inverse characteristic means that
time overcurrent element operates slowly on small values of current above the pickup value and
operates faster when current increases significantly above the pickup value. The phase time
overcurrent element is enabled in the Primary, Alternate settings and
[PROTECTION
ENABLED]
in user interface panel.
Multiple time curves and time dials are available for the phase time overcurrent element to
respectively coordinate with other protection elements in the EVRC2A and other external
devices on the distribution system. ANSI, IEC, ESB, USER and non-standard time current
curves are included in the EVRC2A.
A User Programmable curve option is also available for user to allow creating custom’s time
current curves for more enhanced coordination than the standard curve types.
The Reset type can be either instantaneous or linear. The phase time delay reset mode applies to
the ANSI, IEC, ESB, USER curves. The instantaneous mode is used to coordinate with other
instantaneous reset devices such as a recloser or other protective equipment on the distribution
system. In the instantaneous mode, the time overcurrent element will reset instantaneously when
the measured current level drops below the pickup setting for one cycle.
If the recloser is closed by pressing the CLOSE button on the front panel, or by an remote
control or via SCADA, the phase time overcurrent element is prevented from tripping for a
period specified by the Cold load pickup scheme.
Summary of Contents for EVRC2A-N6-NT
Page 2: ......
