AVEVA™ Plant SCADA

Allen-Bradley PLC-5 via Data Highway - Data Types

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Allen-Bradley PLC-5 via Data Highway - Data Types

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Last UpdatedAug 01, 2025
3 minute read

Note: The Allen-Bradley PLC-5 has many data types. The driver makes a separate request for each different data type, and each request has a finite overhead. It is more efficient to read fewer data types, so you should move the I/O and other data into a few main blocks to be read by Plant SCADA.

Data Types	Address Format	Plant SCADA Data Type
Output image	O:O/o	DIGITAL
Input image	I:O/o	DIGITAL
Status words 0 to 127 (to 128 for w parameter)	S:w/b	DIGITAL
Timer	Tf:w.t	DIGITAL
Counter	Cf:w.c	DIGITAL
Control	Rf:w.r	DIGITAL
Binary	Bf:w/b	DIGITAL
Integer	Nf:w/b	DIGITAL
Sequential Function Chart	SCf:w.s	DIGITAL
Block Transfer	BTf:w.b	DIGITAL
Floating-point	Ff:w/b	DIGITAL
PID	PDf:w.p	DIGITAL
Output image	O:O	BCD / INT / LONG / LONGBCD
Input image	I:O	BCD / INT / LONG / LONGBCD
Status words 0 to 127 (to 128 for w parameter)	S:w	BCD / INT / LONG / LONGBCD
Timer	Tf:w.T	BCD / INT / LONG / LONGBCD
Counter	Cf:w.T	BCD / INT / LONG / LONGBCD
Control	Rf:w.R	BCD / INT / LONG / LONGBCD
Binary	Bf:w	BCD / INT / LONG / LONGBCD
Integer	Nf:w	BCD / INT / LONG / LONGBCD
Sequential Function Chart	SCf:w.S	BCD / INT / LONG / LONGBCD
Block Transfer	BTf:w.B	BCD / INT / LONG / LONGBCD
ASCII	Af:w	BCD / INT / LONG / LONGBCD
BCD	Df:w	BCD / INT / LONG / LONGBCD
Floating-point	Ff:w	REAL
PID	PDf:w.P	REAL
String 82 bytes long	STf:w	STRING

Where:

f	File Number 0 to 999 decimal
:w	Element number 0 to 999 decimal
:O	Element number 0 to 277 octal
/b	Bit Number 0 to 15 decimal
/o	Bit Number 0 to 17 octal
.T	Timer/Counter Sub Element: PRE = Preset Value ACC = Accumulated Value
.t	Timer bits: EN = Enable TT = Timing DN = Done
.C	Control Sub Element: LEN = Length POS = Position
.c	Counter bits: CU = Count Up CD = Count Down DN = Done OV = Overflow UN = Underflow
.r	Control bits: EN = Enable EU = Enable Unloading DN = Done EM = Empty ER = Error UL = Unload IN = Inhibit Comparisons FD = Found
.S	SFC Sub Element: PRE = Preset Value TIM = Elapsed step active time
.s	SFC bits: SA = Scan Active FS = First Scan LS = Last Scan OV = Timer Overflow ER = Error DN = Done
.B	Block Transfer Sub Element: RLEN = Received Length DLEN = Done Length FILE = File ELEM = Element
.b	Block Transfer Bits: EN = Enable TT = Start DN = Done ER = Error CO = Continuous EW = Enable Wait NR = No Response TO = Time Out RW = Read Write
.P	PID Sub Element: SP = Set Point KP = Proportional Gain KI = Integral Gain KD = Derivative Gain BIAS = Output Bias % MAXS = Maximum Scaled Value MINS = Minimum Scaled Value DB = Deadband SO = Set Output % MAXO = Maximum Output % MINO = Minimum Input % UPD = Update Time PVH = PV Alarm High PVL = PV Alarm Low PVDB = PV Alarm Deadband PV = Process Variable ERR = Error OUT = Output DVP = Deviation Alarm + DVN = Deviation Alarm - DVDB = Deviation Alarm Deadband MAXI = Maximum Input MINI = Minimum Input TIE = Tieback %
.p	PID bits: EN = Enable CT = Cascaded Type CL = Cascaded Loop PVT = PV Tracking DO = Derivative Of SWM = Software A/M Mode CA = Control Action MO = Mode PE = PID Equation INI = PID Initialized SPOR = SP Out of Range OLL = Output Limit Low OLH = Output Limit High EWD = Error Within Deadband DVPA = Deviation Low Alarm DVNA = Deviation High Alarm PVLA = PV Low Alarm PVHA = PV High Alarm

Examples

Data Type	DIGITAL
Address	I:1/15
Comment	Input Image - Element Number 1 / Bit Number 15

Data Type	INT
Address	N7:3
Comment	Integer - File Number 7 : Element Number 3

Allen Bradley PLC-5 Series support remapping reads and writes.

AVEVA™ Plant SCADA

Allen-Bradley PLC-5 via Data Highway - Data Types

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Allen-Bradley PLC-5 via Data Highway - Data Types

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