106
FUNCTION CHARACTERISTICS
For all inverse time characteristics, following data applies:
• Asymptotic reference value (minimum pickup value): 1.1 I
E1
>
• Minimum operate time: 0.1 s
• Range where the equation is valid:
[1]
1.1 ≤ I
E1
/I
E1
>
inv
≤ 20
• If I
E1
>
inv
pickup ≥ 2.5 I
E1n
, the upper limit is 10 I
E1n
For all definite time elements the upper limit for measuring is 10 I
E1n
.
All residual overcurrent elements can be enabled or disabled by setting ON or OFF the IE1>
Enable, IE1>>Enableand/or IE1>>>Enableparameters inside the Set \ Profile A (or B or C
or D) \ Residual overcurrent-50N.1/51N.1 \ IE1> Element (IE1>> Element, IE1>>> Element) \ Setpoints
menus.
The first overcurrent element can be programmed with definite or inverse time characteristic by
setting the IE1>Curve parameter (
DEFINITE, IEC/BS A, IEC/BS B, IEC/BS C, ANSI/IEE
MI,ANSI/IEEVI,ANSI/IEEEI,EM) available inside the Set \ Profile A (or B or C or D) \ Residual
overcurrent-50N.1/51N.1 \ IE1> Element \ Setpoints menu.
The trip of IE1> element may be inhibited by the start of the second and/or third element (IE1>>,
IE1>>>) by setting ON the Disable IE1> by start IE1>>, Disable IE1> by start IE1>>> (IE1>di-
sbyIE1>>,IE1>disbyIE1>>>) parameters available inside the Set \Profile A (or B or C or D) \
Residual overcurrent-50N.1/51N.1 \ IE1>> Element (IE1>>> Element) \ Setpoints menus.
Similarly the trip of the I
E
>> element may be inhibited by start of the third element (I
E
>>>) by setting
ON the Disable IE>> by start IE>>> (IE>>disbyIE>>>) parameter available inside the Set \ Profile
A (or B or C or D) \ Residual overcurrent-50N.1/51N.1 \ IE1>>> Element \ Setpoints menu.
All the named parameters can be set separately for Profile A, B, C, D.
An adjustable reset time delay is provided for every threshold t
E1>RES
, t
E1>>RES
, t
E1>>>RES
).
Breaker failure (BF)
Each thresholds (IE1>, IE1>>, IE1>>>) can be associated to BF protection by activating the relative
parameter in the matrices “Selection of function tripping for BF” in relevant BF menus
[2]
:
• Set \ Profile A (or B or C or D)\ Breaker failure
Note 1 When the input value is more than 20 times the set point , the operate time is limited to the value corresponding to 20 times the set point
Note 2 The common settings concerning the Breaker failure protection are adjustable inside the Breaker Failure - BF menu.
t-int-F50N-51N.ai
I
E1
I
E1
>> I
E1
>>>
t
E1
>
t
E1
>>
t
E1
>>>
I
E1
>
t
General operation time characteristic for the residual overcurrent elements - 50N.1/51N.1
TRIP
Timers-F50N-51N.ai
IE1> Start
IE1> Trip
t
E1>
t
E1>
RESET
INPUT
t
E1>RES
t
E1>RES
t
E1>RES
t
IE> element residual overcurrent (50N.1/51N.1) - Timers
XMR-T EQUIPMENT MANUAL
Ed. 2.9 - 02/2021