EasyManuals Logo

ABB rec670 Applications Manual

ABB rec670
658 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #181 background imageLoading...
Page #181 background image
The function is divided into two parts. The SOTF function will give operation from
step 2 or 3 during a set time after change in the position of the circuit breaker. The
SOTF function has a set time delay
. The under time function, which has 2
nd
harmonic
restrain blocking, will give operation from step 4. The 2nd harmonic restrain will
prevent unwanted function in case of transformer inrush current. The under time
function has a set time delay.
Below the settings for switch on to fault logics are described.
SOTF: This parameter can be set: Disabled/SOTF/Under Time/SOTF+Under Time.
SOTFSel: This setting will select the signal to activate SOTF function; CB position
open/CB position closed/CB close command.
StepForSOTF: If this parameter is set on step 3, the step 3 pickup signal will be used as
current set level. If set on step 2, the step 2 pickup signal will be used as current set
level.
HarmBlkSOTF: This is used to On/Off harmonic restrain during SOTF conditions.
tSOTF: Time delay for operation of the SOTF function. The setting range is 0.000 -
60.000 s in step of 0.001 s. The default setting is 0.100 s
t4U: Time interval when the SOTF function is active after breaker closing. The setting
range is 0.000 - 60.000 s in step of 0.001 s. The default setting is 1.000 s.
ActUndrTimeSel: Describes the mode to activate the sensitive undertime function. The
function can be activated by Circuit breaker position (change) or Circuit breaker
command.
tUnderTime: Time delay for operation of the sensitive undertime function. The setting
range is 0.000 - 60.000 s in step of 0.001 s. The default setting is 0.300 s
8.4.3.5 Settings for each step (x = 1, 2, 3 and 4)
M15282-9 v12
Operation: Sets the protection to Enabled or Disabled.
DirModeSelx: The directional mode of step x. Possible settings are Disabled/Non-
directional/Forward/Reverse.
Characteristx: Selection of time characteristic for step x. Definite time delay and
different types of inverse time characteristics are available.
Inverse time characteristic enables fast fault clearance of high current faults at the same
time as selectivity to other inverse time phase overcurrent protections can be assured.
This is mainly used in radial fed networks but can also be used in meshed networks. In
meshed networks, the settings must be based on network fault calculations.
1MRK 511 401-UUS A Section 8
Current protection
Bay control REC670 2.2 ANSI 175
Application manual

Table of Contents

Other manuals for ABB rec670

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the ABB rec670 and is the answer not in the manual?

ABB rec670 Specifications

General IconGeneral
BrandABB
Modelrec670
CategoryControl Unit
LanguageEnglish

Related product manuals