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ABB | SACE Tmax XT
Startup Protection The function, which can be activated for protections S, I, G, S2, D and UP (if available and enabled), allow
the protection threshold (StartUp threshold) to be changed for a period that can be set by the user
(Startup time).
NOTE: for UP protection, startup means the time for which the protection is disabled
The period begins after a threshold has been exceeded (activation threshold), user-programmable via
Ekip Connect or system bus, valid and verified for all phase currents.
The Startup condition elapses after Startup time and re-activates the next time the activation threshold
is exceeded
NOTE: startup does not occur again until at least one current remains above activation
threshold level
A graphic representation with S protection follows:
Figure 24
Block functions Six blocks can be configured for certain protections by means of the service connector (via Ekip Connect)
or communication via system bus. These blocks are useful for deactivating the protections relating to
programmable events:
Block name Description
BlockOnProgStatusA Block active if programmable status A is true
BlockOnProgStatusB Block active if programmable status B is true
BlockOnProgStatusC Block active if programmable status C is true
BlockOnProgStatusD Block active if programmable status D is true
Block active during StartUp time (if StartUp for the specific protection
BlockOnStartUp
is available and activated)
BlockOnOutOfFrequency Block active if frequency measured is not within 30 Hz to 80 Hz range
Each block is independent and has its own activation command (Block On); however, each protection can
be configured with several block conditions (operation in OR logic condition).
The protections which have blocks are: S, I, G, MCR, S2, D, S(V), S2(V), UV, OV, VU, UV2, OV2, UP, OP, RP, RQ,
OQ, RV, UF, OF, UF2, OF2, ROCOF, UC, U, R Jam, R Stall.
IMPORTANT: the blocks can cause:
• increase of protection trip times (max: + 30 ms), owing to verification of the event itself
(example: (frequency check)
• undesired deactivation of the protection, if the block is associated with statuses or
signals to modules via local bus and auxiliary power supply is absent. In this case, it may
be useful to also consider the status of the auxiliary power supply (Supply from Vaux)
when programming the event
• undesired deactivation of the protection, if the block is associated with frequency
measurements and the voltage is less than the minimum calculation threshold
IMPORTANT: if the function is activated, the blocks are deactivated during startup (except
for BlockOnStartup, which functions during this period)
70 | © 2022 ABB | 1SDH002031A1002 - ECN000212994 Protections | 10 - Additional protections and functions