Atlas Copco PowerMACS 4000, User Manual

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PLC
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Variable Type Use
DEVICE_STATUS DEVICE_STATUS_
ARR This variable indicates status of devices.
The variable is an array of BYTE where each element
represents the device with the number equal to the array
index number.
That is, DEVICE_STATUS[10] shows the status of the
device with device number 10.
The status value corresponds to following:
0: NOSTATUS
1: WORKING
2: IDLE_OK
3: IDLE_NOK
4: OUTOFORDER
The following shared memory variable can be used for handling of process data:
Variable Type Use
FB_PROCDATA_STORED BYTE The PowerMACS system will write True to it when it has written
anything to the Process Data output area of the fieldbus.
The System will never write False to it. In order to detect when it is
set you must clear it from inside the PLC.
CYCLDATA_VAR_UPDATED BYTE This input is set True when there are new cycle data available in
CycleData_Var.
It can be set False by the PLC program to be able to check when
new cycle data has arrived.
UPDATE_EXTCO_2 BYTE When this variable is written with a positive flank (0->1) all
variables controlled by the EXTCO2_out area will be updated. The
PLC program must reset it to 0 afterwards, not faster than one
execution loop. See sub chapter Access to PLC data of Serial
Communication.
A shared memory variable can be written to from the PowerMACS system as well as from the
PowerMACS PLC.
FB_PROCDATA_STORED
may be used in many different ways depending on type of application. For
example: In a system where cycle data is generated after each cycle (also at emergency stop) and this
data is automatically loaded to the fieldbus device one way of using it is as follows:
1. Have the PowerMACS PLC write FALSE to the variable FB_PROCDATA_STORED just before, or
simultaneously with, the start signal.
2. Wait for the PowerMACS system to write TRUE to the variable FB_PROCDATA_STORED before
indicating that the cycle is finished to the fieldbus master.