Siemens 7SR157 Argus, Руководство пользователя

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7SR157 Technical Manual
Chapter 4 - Page 22 of 58 © 2016 Siemens Protection Devices Limited
Truncation
Calculations are performed as 32 bit. The 16 bit value is the lowest 16 bits of the 32 bit value. Therefore,
when values overflow the returned value is the lowest 16 bits of the calculated value. For Example, if the
value is 85400 = 14D98h, the value returned would be the lowest 16 bits = 4D98h which equals 19864.
4.2.5 EVENT
MODBUS does not define a method for extracting events; therefore a private method has been defined
based on that defined by IEC60870-5-103.
The EVENT register contains the earliest event record available. The event record is 8 registers (16
bytes) of information, whose format is described below. When this record has been read it will be
replaced by the next available record. Event records must be read completely; therefore the quantity
value must be set to 8 before reading. Failing to do this will result in an exception code 2. If no event
record is present the exception code 2 will be returned. The EVENT register should be polled regularly
by the master for events.
The EVENTCOUNT register can be checked periodically to determine how many events are stored.
The format of the event record is defined by the zero byte. It signifies the type of record which is used
to decode the event information. The zero byte can be one of the following.
Format
The format of the event record is defined by the zero byte. It signifies the type of record which is used
to decode the event information. The zero byte can be one of the following.
Type Description
1 Event
2 Event with Relative Time
4 Measurand Event with Relative Time
The following table describes the fields in the event record.
Key Description
FUN Function Type, as defined for IEC870-5-103.
INF Information Number, as defined for IEC870-5-103.
DPI Measurand Event with Relative Time, values 1 = OFF, 2 = ON.
ms L Time Stamp Milliseconds low byte.
ms H Time Stamp Milliseconds high byte.
Mi Time Stamp Minutes (MSB = invalid, time not set > 23 hours).
Ho Time Stamp Hours (MSB = Summer time flag).
RT L Relative Time low byte.
RT H Relative Time high byte.
F# L Fault Number low byte.
F# H Fault Number high byte.
Meas Measurand format R32.23, sent least significant byte first.
The following tables show the fields in the different event records as they are returned.
Byte 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Content 1 0 FUN INF DPI 0 0 0 0 0 0 0 ms L
ms
H
Mi Ho
Event Type 1 Format.