ABB Relion 670 series, Technical Reference Manual, Page: 458 / 1232

_
_
ln
final lockout release
lockout release
final n
t
t
æ ö
Q - Q
= - × ç
÷
ç ÷
Q - Q
è ø
EQUATION1170 V1 EN
(Equation 95)
Here the final temperature is equal to the set or measured ambient temperature. The
calculated time to reset of lockout is available as a real figure signal, TENRECL.
In some applications the measured current can involve a number of parallel lines. This
is often used for cable lines where one bay connects several parallel cables. By setting
the parameter
IMult to the number of parallel lines (cables) the actual current on one
line is used in the protection algorithm. To activate this option the input MULTPU
must be activated.
The protection has a reset input: RESET. By activating this input the calculated
temperature is reset to its default initial value. This is useful during testing when
secondary injected current has given a calculated “false” temperature level.
Section 7
1MRK505222-UUS C
Current protection
452
Technical reference manual