Areva MiCOM P125, Technical Manual

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Commissioning and Maintenance P12y/EN CM/C22
MiCOM P125/P126 & P127 Page 17/24
Checks:
•
Alarm message on the LCD display.
•
Alarm LED flashes.
•
Trip LED on
•
I> threshold LED on (if programmed).
•
Trip output closes.
•
I> threshold output closes (if programmed).
Delay type: Definite time tI>
•
Apply a current into one of the phases and measure the time delay tI> by pre-setting
the current above the I> threshold (I injected > 2 x I threshold).
•
Apply a current onto one of the phases and measure the time delay tI> by pre-setting
the current above the I> threshold (I injected > 10 x I threshold).
Checks:
•
Alarm message on the LCD display for I> after that the setting trip delay time is
expired.
•
Alarm LED flashes > after that the setting trip delay time is expired.
•
Trip LED on after that the setting trip delay time is expired.
•
I> threshold LED on (if programmed) > after that the setting trip delay time is expired.
•
Trip output closes > after that the setting trip delay time is expired..
•
I> threshold output closes (if programmed) > after that the setting trip delay time is
expired.
Delay type: Inverse time (IDMT)
Used threshold for this test:
•
I>, tI>
•
Supply the relay, inject a current equal to 2 x I> threshold into one of the earth current
inputs. Repeat the operation for various current values (n x Ie threshold with n ranging
from 4 to 10, for example). Check that the values measured correspond to those
indicated in the table below (for TMS=1).
IEC curves
Type of curve Tripping time (in seconds) for TMS =1
IEC 2 x I threshold 10 x I threshold
Nominal Min - Max Nominal Min - Max
STI 1.78 1.62 - 1.98 0.5 0.45 - 0.55
SI 10.1 9.1 - 11.1 3 2.7 - 3.3
VI 13.5 12.2 - 14.9 1.5 1.35 - 1.65
EI 26.7 24 - 29.5 0.8 0.72 - 0.88
LTI 120 108 - 132 13.3 12 - 14.6