Protection Function Control; Pickup Logic Of Device; Functional Description - Siemens Siprotec 7UM611 Manual

2.34

Protection Function Control

The function logic coordinates the sequence of both the protective and ancillary func-
tions, processes the functional decisions, and data received from the system.
In particular, this includes:
• Pick-up logic
• Tripping logic
• Fault display on the LEDs/LCD
• Statistics

2.34.1 Pickup Logic of Device

This section describes the general pickup and spontaneous messages in the device
display.

2.34.1.1 Functional Description

General Pickup The pickup signals for all protection functions in the device are logically OR-combined,
and lead to the general device pickup. It is initiated by the first function to pickup, ends
when the last function drops out and is reported as general device pickup.
General device pickup is a precondition for a series of internal and external subse-
quent functions. The following are among the internal functions controlled by general
device pickup:
• Opening of fault case: From general device pickup to device drop out, all fault mes-
• Initialization of fault storage: The storage and maintenance of fault values can also
• Generation of Spontaneous messages in the device display: Certain fault messag-
Display Spontane- Spontaneous messages are fault messages that appear in the display automatically
ous Annunciations when general device pickup has occurred. For the 7UM61, these messages include:
"Relay Pickup"":
"Relay Trip":
"PU Time":
"Trip time":
Note that the thermal overload protection does not have a pickup comparable with the
other protection functions. The PU Time is first started with the trip command, thereby
opening a fault case. The dropout of the thermal image of the overload protection ends
the fault case and, thereby the running PU Time.
7UM61 Manual
C53000-G1176-C127-3
sages are entered in the trip log.
be made dependent on the occurrence of a tripping command.
es are displayed in the device display as so-called spontaneous messages (see
below "Display—Spontaneous Messages"). This display can be made dependent
on the occurrence of a trip command.
2.34 Protection Function Control
the protection function that last picked up
the protection function that last initiated a trip signal;
the operating time from general pickup to dropout of
the device, in ms;
the operating time from general pickup to the first trip
command of the device, in ms;
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