scheider electric MiCOM P746, Техническое руководство

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Operation P746/EN OP/G31
MiCOM P746 (OP) 5-
19
OP
3. OPERATION OF NON PROTECTION FUNCTIONS
3.1 Programmable scheme logic
3.1.1 Level settings
Name Range Step Size
Time delay t 0-14400000ms 1ms
3.1.2 Accuracy
Output conditioner timer
Setting
±
2% or 50ms whichever is greater
Dwell conditioner timer
Setting
±
2% or 50ms whichever is greater
Pulse conditioner timer
Setting
±
2% or 50ms whichever is greater
3.2 IRIG-B signal only
If a satellite time clock signal conforming to IRIG-B is provided and the relay has the optional
IRIG-B port fitted, the satellite clock equipment should be energised.
In the event of the auxiliary supply failing, with a battery fitted in the compartment behind the
bottom access cover, the time and date will be maintained. Therefore, when the auxiliary
supply is restored, the time and date will be correct and not need to be set again.
3.3 Trip LED logic
The trip LED can be reset when the flags for the last fault are displayed or via dedicated
ddbs. The flags are displayed automatically after a trip occurs, or can be selected in the fault
record menu. The reset of trip LED and the fault records is performed by pressing the
key
once the fault record has been read.
3.4 Function keys
The P746 relay offers users 10 function keys for programming any operator control
functionality via PSL. Each function key has an associated programmable tri-colour LED that
can be programmed to give the desired indication on function key activation.
These function keys can be used to trigger any function that they are connected to as part of
the PSL. The function key commands can be found in the ‘Function Keys’ menu (see
Settings section, P746/EN ST). In the ‘Fn. Key Status’ menu cell there is a 10 bit word which
represent the 10 function key commands and their status can be read from this 10 bit word.
In the programmable scheme logic editor 10 function key signals, which can be set to a logic
1 or On state, as described above, are available to perform control functions defined by the
user.
The “Function Keys” column has ‘Fn. Key n Mode’ cell which allows the user to configure the
function key as either ‘Toggled’ or ‘Normal’. In the ‘Toggle’ mode the function key DDB signal
output will remain in the set state until a reset command is given, by activating the function
key on the next key press. In the ‘Normal’ mode, the function key DDB signal will remain
energized for as long as the function key is pressed and will then reset automatically. A
minimum pulse duration can be programmed for a function key by adding a minimum pulse
timer to the function key DDB output signal.
The “Fn. Key n Status” cell is used to enable/unlock or disable the function key signals in
PSL. The ‘Lock’ setting has been specifically provided to allow the locking of a function key
thus preventing further activation of the key on consequent key presses. This allows function
keys that are set to ‘Toggled’ mode and their DDB signal active ‘high’, to be locked in their
active state thus preventing any further key presses from deactivating the associated
function. Locking a function key that is set to the “Normal” mode causes the associated DDB
signals to be permanently off. This safety feature prevents any inadvertent function key
presses from activating or deactivating critical relay functions.