GE Multilin G650, Manual

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B-18 G650 Generator Protection & Control System GEK-113285A
B.6 EVENTS STATUS REQUEST(ALARMS) APPENDIX B
B
B.6.4 ACKNOWLEDGEMENT OF EVENTS (ALARMS)
For acknowledging the alarms we must simply write message to the 0xf324 address with 12 data registers. Each bit means
an event, if we want to acknowledge an alarm, its corresponding bit must be set to ‘1’ (in order within the 192 bits).
NOTE:
it must be borne in mind the independence of the acknowledgement condition, for its reading and its change,
depending on the communication channel
There are 6 channels:
LOCAL:
by MMI or COM-2 (front and rear accessible).
REMOTE:
by COM-1
NET 1:
nowadays by any net communication
NET 2:
(it does not exist in version 1.4x and lower)
NET 3:
(it does not exist in version 1.4x and lower)
NET 4:
(it does not exist in version 1.4x and lower)
B.6.5 VIRTUAL INPUTS WRITING
For forcing Virtual Inputs, a message with 4 indivisible records must be written at address, so that each bit corresponds to a
Virtual Input. Values will not be correct if the first 4 records are not written in the same message. The first 32 are LATCHED
(internally stored with RAM with battery), and the last 32 are SELF-RST (activated to 1 and deactivated in the next pass by
the PLC).
For reading the status of Virtual Inputs, it is necessary to start with address 0x0083(bit 0x004) up to 0x0087 (bit 0x0200).
B.6.6 USER MAP
G650 units incorporate a powerful feature called ModBus User Map, that allows to read 256 non-consecutive data records
(settings and statuses). It is often required for a master computer to interrogate continuously several connected slave
relays. If those values are dispersed along the memory map, reading them may require several transmissions, and this may
cause a communications overload. The User Map can be programmed to get several memory addresses together in a
block of consecutive addresses of the User Map, so that they can be accessible with a single reading operation.
The user Map has two sections:
A record index area (addresses 0x3384 to 0x3483), containing 256 statuses and/or setting record addresses.
A record area (addresses 0xF330 to 0xF42F), containing the values for addresses indicated in the index area.
Data records that are separated in the rest of the memory map can be remapped to an address of an adjacent record in the
User Map area. For programming the map this way, addresses for the required records must be written in the index area.
This avoids the need for several reading operations, thus improving data transmission yield.
For instance, if Contact Outputs from Board F (address 0x008B) and Board G (address 0x00B0) values are required, these
addresses must be mapped as follows:
In address 0x3384, write 0x008B.
In address 0x3385
XXX write 0x00B0.
The reading of records 0xF330 and 0xF331, applying the corresponding bit masks, will provide the required information
about the two boards Contact Outputs.
NOTE:
Only single data can be set in the map, data that are in the memory map and can be read. This feature is not valid
for events, waveform records, etc. that are not located in a map address.