ABB eVM1 Installation And Service Instructions Manual page 59

When the close command is removed, the anti-pumping function is reset. This is a Global function,
i.e. the function manages both Local and Remote O/C commands.
Close Command
Open Command
C
O
CB Status
Fig. 43
14.5.6.8 Simultaneous O-C Commands
This function ensure that closing is disabled when an opening command is active at the same time
In the case of simultaneous open and close commands (when closing and opening have different
delays before being considered valid, e.g. 10ms for closing and 20ms for opening), opening has
higher priority and closing will not be executed, independently of the CB position (e.g. with the Re-
close function, too, opening has higher priority): the ED will not close the CB if – at the end of the
closing signal delay – the delay time of the opening signal is already running. See figure below:
Close Command
Open Command
c
CB Status
o
Fig. 44
In correspondence with release of the Open command, if the Close signal is still high the CB will
not be closed because the Close command is only considered valid on positive edge front.
If the closing operation is initiated and in the meantime a valid Open Command has arrived, it has
to be stored and performed as soon as possible (as soon as the close operation is ended).
In the case where the CB is already closed, the CB opens.
Command Valid
Command
Valid
Time
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