11
Recorded
information
The parameter values measured at the moment
when a fault occurs or at the trip instant are
recorded in the registers. The recorded data,
except for some parameters, are set to zero by
pressing the push buttons STEP and PRO-
GRAM simultaneously. The data in normal
registers are erased if the auxiliary voltage supply
to the relay is interrupted, only the set values and
certain other essential parameters are maintained
in non-volatile registers during a voltage failure.
The number of registers varies with different
relay module types. The functions of the regis-
ters are illustrated in the descriptions of the
different relay modules. Additionally, the sys-
tem front panel of the relay contains a simplified
list of the data recorded by the various relay
modules of the protection relay.
All D type relay modules are provided with two
general registers: register 0 and register A.
Register 0 contains, in coded form, the informa-
tion about e.g. external blocking signals, status
information and other signals. The codes are
explained in the manuals of the different relay
modules.
Register A contains the address code of the relay
modul which is reqiured by the serial communi-
cation system.
Submenu 1 of register A contains the data trans-
fer rate value, expressed in kilobaud, of the serial
communication.
Submenu 2 of register A contains a bus commu-
nication monitor for the SPAbus. If the protec-
tion relay, which contains the relay module, is
linked to a system including a contol data
communicatoe, for instance SRIO 1000M and
the data communication system is operating,
the counter reading of the monitor will be zero.
Otherwise the digits 1...255 are continuously
scrolling in the monitor.
Submenu 3 contains the password required for
changing the remote settings. The address code,
the data transfer rate of the serial communica-
tion and the password can be set manually or via
the serial communication bus. For manual set-
ting see example 1.
The default value is 001 for the address code, 9.6
kilobaud for the data transfer rate and 001 for
the password.
In order to secure the setting values, all settings
are recorded in two separate memory banks
within the non-volatile memory. Each bank is
complete with its own checksum test to verify
the condition of the memory contents. If, for
some reason, the contents of one bank is
disturbed, all settings are taken from the other
bank and the contents from here is transferred to
the faulty memory region, all while the relay is
in full operation condition. If both memory
banks are simultaneously damaged the relay will
be be set out of operation, and an alarm signal
will be given over the serial port and the IRF
output relay
