In the register of the SOTF function is recorded activated “On” event process data. In the table below is
presented the structure of SOTF function register content. This information is available in 12 last
recorded events for all provided instances separately.
Table. 5.5.6. - 206. Register content.
Date & Time
Event
code
SG in use
SOTF remaining time
SOTF been active time
5.5.7. Synchrocheck function ΔV/Δa/Δf (25)
To ensure safe closing of the circuit breaker between two systems it is important to check the
synchronization. Closing the circuit breaker while the systems are in asynchronous state can cause
several problems like current surges which damage the interconnecting elements. Synchrocheck has
three stages SYN1, SYN2 and SYN3. SYN1 supervises the synchronization condition between U4
channel and the selected input voltage. SYN2 supervises the synchronization condition between U3
channel and the selected input voltage. SYN3 supervises the synchronization condition between U3
and U4 channels.
Figure. 5.5.7. - 149. Example connection of synchrocheck function in 3LN+U4 mode when the SYN1 stage is in use and UL1 is
the reference voltage.
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
252