Trip Curves For Function G; Main Functions; Measurement; Self-Monitoring - ABB Emax E1 Installation And Service Instructions Manual

12.4.8.4. Trip curves for function G

12.5. Main functions

12.5.1. Measurement

The current measuring (ammeter) function is available in all versions of the PR121/P unit.
This function is accessible by means of test unit BT030-USB, Ekip T&P (connected to a PC) and PR010/T, or by means of HMI030.
The measurement tolerance margins are:
Type of measurement
Phase and neutral current
Earth fault current
The relay allows the maximum current reading to be periodically recorded: this function must be enabled with test unit BT030-
USB or Ekip T&P, and requires auxiliary voltage.

12.5.2. Self-monitoring

The PR121/P unit provides certain self-monitoring functions that allow faults or setting errors to be identifi ed more easily. Faults
are signalled by a combination of led lights.
The functions are as follows:
 Rating Plug validity.
 Checks to fi nd out whether the current sensors (CS) are connected correctly.
 Watchdog for proper connection of the Trip Coil (TC ).
 Hw Trip protection. If activated, a CB opening command is transmitted through activation of the TC if sensors are disconnected
or if the Rating Plug is not connected/faulty. This function can be activated by means of test unit PR010/T, BT030-USB or Ekip
T&P.
Model L6555
t = k
Range of values measured by the relay
0,05 ... 16 In
0,05 ... 4 In
k
t =
2
I
Standard operation range
Range
0,3 ... 6 In
0,3 ... 4 In
Apparatus
Doc. no.
1SDH000460R0002
Tolerance %
± 1,5
± 1,5
Scale
Emax
Page No
44/74