Industrial Automation Protocols

Comparison of Different Industrial Automation Communication Protocols like ARCNET. AS-I, CAN open, CONTROL NET, DEVICE NET, FOUNDATION FIELD BUS, INDUSTRIUAL ETHERNET, INTERBUS-S, LON Works, MODBUS PLUS, PROFIBUS DP, PROFIBUS PA, SDS SERIPLEX, WORLD FIP

Process Control Industrial Automation Protocols

Automation Protocol Type	Technology Developer	Year Introduced	Governing Standards	Openness
ARCNET	Datapoint / SMC	1975	ANSI 878	Chips, boards, ANSI docs
AS-I	AS-I Consortium	1993	Submitted to IEC	AS-II, C, Market items
CAN open	Phillips / CiA	1992	CiA	6 chip vendors 100+ products
CONTROL NET	Allen Bradley	1997	Controlnet International	Chip from AB multiple vendors with products
DEVICE NET	Allen Bradley	1994	ISO 11898 &11519	6 chip vendors 100+ products
FOUNDATION FIELD BUS	Fieldbus Foundation	1995	ISA SP50 / IEC TC65	Chips / software from multiple vendors
INDUSTRIUAL ETHERNET	Intel / DEC /Xeros; HP Hirschmann synergetics	1979;1998	IEEE 802.3	Multiple vendor support through Industrial Ethernet trade association
INTERBUS-S	Pheonix Contact	1984	DIN 19258	Product from over 400 manufactures
LON Works	Echolon Corp	1991	ASHRAE OF BAC net	Public documentation on protocol
MODBUS PLUS	AEG Modicon	1981	None	Controlled by AEG modicon. Multiple vendor support through Modconnect vendor program
PROFIBUS DP/PA	Profibus Trade Organisation	DP:1994 PA:1995	DIN 19245 part 3/4	Product from over 150 vendors
SDS	Honeywell	1994	Honeywell spec submitted to IEC, ISO11989	6 chip vendors 200+ product
SERIPLEX	APC Inc	1990	Seriplex Spec	Chips available multiple interfaces
WORLD FIP	World FIP	1988	IEC 1158-2	Multiple chip vendors

Physical Characteristics

Automation Protocol Type	Network Topology	Physical Media	Maximum Devices (Nodes)	Maximum Distance
ARCNET	Bus, Multidrop, Star	Twisted pair coax fiber	255 nodes	6 km
AS-I	Bus, Ring,tree,star of all	Two wire cable	31 slave	100 m          300m with repeaters
CAN open	trunkline / dropline	Twisted -pair for signal and power	64 nodes	500 m
CONTROL NET	Trunkline, tree, star	Coax R6/U fiber	99 nodes	5 km coax,   30 km fiber
DEVICE NET	Trunkline / droplie with branching	Twisted – pair for signal and power	64 nodes	500 m
FOUNDATION FIELD BUS	Multidrop with bus powered devices	Twisted pair	240/segment 6500 segments	1900m @31.25 kbps 500m @2.5 Mbps
INDUSTRIUAL ETHERNET	Star, bus	10Base-T, 10Base-FL (fiber)          100 Base-Tx	48 bit address of    247 nodes	1500m
INTERBUS-S	Segmented with T drops	Twisted-pair, fiber, slip ring	256 nodes	400m/segment 12.8 km total
LON Works	Bus, ring, loop, star	Twisted-pair, fiber, power line	3200 / domain	2000 m @ 78kbps
MODBUS PLUS	Multidrop network segment with bridge capabilities	RS-485, transformer isolated	32,64 max per segment. Max 5 level routing	1500 ft(450M) repeaters can extend 6000 ft(1800M)
PROFIBUS DP/PA	Line star & ring	Twisted Pait or fiber	127 nodes	24 km (fiber)
SDS	Trunkline / dropline	Twisted pair for signal and power	64 nodes, 126 address	500m
SERIPLEX	Tree, loop, ring, multidrop star	4-wire shrouded cable	500+ device	500+ ft
WORLD FIP	Bus	Twisted-pair, fiber	256 nodes	up to 40 km

Transport Mechanism

Automation Protocol Type	Communication methods	Network Speed	Data Transfer Size	Arbitration Method	Error Checking	Diagnostics
ARCNET	Peer to Peer	31.25kbps to 10 Mbps	508 bytes	Token	16 bit CRC	Built in
AS-I	Master/slave with cyclic polling	167 kbps	31 slaves with 4 in and 4 out	Master/slave with cyclic polling	Manchester code hamming-2 partly	slave fault device fault
CAN open	Master/slave	1Mbps,    500 kbps, 250 kbps, 125kbps	8 – bytes variable message	Carrier-sonac multiple access	CRC check	Bus monitor
CONTROL NET	Master/slave, multi-master, peer to peer	5 Mbps	510 bytes	Time -slice multiple access (CTDMA)	CCITT with 16 bit polynomial	Device slave faults
DEVICE NET	Master/slave, multi-master, others	500 kbps, 250 kbps, 125 kbps	8-bytes variable message	Carrier-sonac multiple access	CRC check	Bus monitoring
FOUNDATION FIELD BUS	Client/server publisher/subscriber, Event notification	31.25 kbps 1 Mbps    2.5 Mbps	16.6 M objects / device	Deterministic centralised scheduler, multiple backup	16 bit CRC	Remote diagnostics network monitors, parameter status
INDUSTRIUAL ETHERNET	CSMA/CD	10 Mbps 100 Mbps	1500 bytes data	Collision detection	32 bit CRC	CD, network management
INTERBUS-S	Master/slave with total frame transfer	500 kbps, full duplex	512 bytes h,s., unlimited blocks	None	16 bit CRC	Segment location of CRC error and cable break
LON Works	Master/slave Peer tp peer	1.25 Mbs full duplex	228 bytes	Carrier sense multiple access	16 bit CRC	Database of CRC error and device error
MODBUS PLUS	Token passing	1 Mbps	256 bytes data + header	Peer to peer Token passing	16 bit CRC	Local chip and software
PROFIBUS DP/PA	Master/slave Peer to peer	DP upto 12 Mbps Pa 31.25 kbps	244 bytes	Token passing	HD4 CRC	Station,module & channel diagnostics
SDS	Master/slave, peer to peer, multicase, multi-master	1 Mbps,   500 kbps, 250 kbps, 125 kbps	8 – bytes variable message	Carrier-sonac multiple access	CRC check	Bus monitoring diagnostic slave
SERIPLEX	Master/ slave Peer to peer	200 Mbps	7680 / transfer	Sonal multiplexing	End of frame	Cabling problems & echo check
WORLD FIP	Peer to peer	31.25 kbps, 1&2.5mbps, 6Mbps fiber	No limit, variables 128 bytes	Central arbitration	16 bit CRC data “freshness” indicator	Device message time-out, redundant cabling

Performance

Automation Protocol Type	Cycle time: 256 discrete 16 nodes with 16 I/O’s	Cycle time: 128 analog 16 nodes with 8 I/O’s	Block transfer of 128 bytes 1 node
ARCNET	<2 ms @ 2.5 mbps	<2ms @ 2.5 Mbps	<2 ms @ 2.5 Mbps
AS-I	4.7 ms	Not possible	Not possible
CAN open	Not available	Not available	Not availavle
CONTROL NET	2 ms	2 ms	2 ms
DEVICE NET	2.0 ms master / slave polling	10 ms master / slave polling	4.2 ms
FOUNDATION FIELD BUS	100ms@31.25kbps < 1ms @ 2.5 Mbps	600 ms @ 31.25 kbps <8ms @ 2.5 Mbps	36 ms @ 31.25 kbps 0.45 ms @ 2.5 mbps
INDUSTRIUAL ETHERNET	Network dependent	Network dependent	Network dependent
INTERBUS-S	1.8 ms	7.4 ms	140 ms
LON Works	20 ms	5 ms @ 1 Mbps	5 ms @ 1 Mbps
MODBUS PLUS	Not available	Not available	Not availavle
PROFIBUS DP/PA	Configuration dependent typical   < 2 ms	Configuration dependent typical < 2 ms	Not availavle
SDS	<1ms event driven	< 1ms per event 10.4 ms	2 ms @ 1 mbps
SERIPLEX	1.32 ms@200kbps, m/s	10.4 ms	10.4 ms
WORLD FIP	2 ms @ 1 Mbps	5 ms @ 1 Mbps	5 ms @ 1 mMbps

Summary of Process Control Industrial Automation Protocols