Table of Contents
Advertisement
12.3. User interface
The graphic interface of relay PR121/P allows the protections and general state of the relay itself to be adjusted and displayed.
5
1
2
3
4
Rifer.
Description
1
Alarm indicator LED for protection function L
2
Section dedicated to protection S (not present for models PR121/P LI)
3
Alarm indicator LED for protection function I
4
Alarm indicator LED for protection function G (not present for models PR121/P LSI and PR121/P LI)
5
Dip switch position indications, with reference to the L, S, I, G protection thresholds
6
Dip switch for setting the thresholds of protections L (I1), S (I2), I (I3), G (I4)
7
LEDs for signalling Alarm state of protections L, S, I and G, Pre-alarm L, Power status indicator
8
Dip switch for setting the tripping times of protections L (t1), S (t2), G (tI4)
9
Dip switch position indications, with reference to the thresholds of the tripping times L, S, G
10
Position indicator for the DIP switches for setting the neutral protection
11
Serial number of the relay
12
Rating plug
13
"i Test" test and info button
14
Test connector for external modules PR030/B, BT030-USB, Ekip T&P, PR010/T)
12.3.1. Dip switches
IThe dip switches on the front of unit PR121/P are used for regulating the tripping thresholds of each protection and the tripping time.
The available combinations are given alongside each group of dip switches.
The dip switches for regulating the tripping times of protections S (t2) and G (t4) can also be used for selecting the trip-
ping curve:
Fixed time tripping curve. The following relation is used: t=k.
Inverse time tripping curve. The relation between the tripping time and over-current is given by the formula: t=k/I
The dip switch settings can be changed when the relay unit is on and without alarms: updating is immediate. The unit need not
be restarted.
WARNING: The settings are inhibited if the relay is in the alarm condition (signalled by LEDs): settings changed
by the user when the relay is in the alarm condition will not be recorded until the alarm condition ceases.
An example of the dip switch setting for the protection L function, with 2000A Rating Plug (In= 2000A) is given below.
12.3.2. LED
The following table shows how the LEDs are managed in accordance with the IEC standard 60073 (and clause 4.2.3.2 in particular).
Model
L6555
6
7
8
Apparatus
Doc. no.
1SDH000460R0002
9
10
11
Emax
12
13
14
2
Scale
Page No
38/74
Hide quick links:
Advertisement
Table of Contents
