Difference between Triconex PLC & Other PLC

R

Thread Starter

RAVI

We are using Triconex PLC in our Plant Emergency Shutdown Systems. As we know Triconex is Fault Tolerant and a very rugged PLC but costlier as compared to other make PLCs

Does that mean that if Money is not adeciding Factor while
purchasing PLC one should always opt for Triconex PLCs ? Is it the best PLC available ??

Why is it that PLCs of other make such as Modicon, Siemens, Allen Bradley are generally not used in Emergency Shutdown System Applications ?

What are the disadvantages of Triconex PLC ?
I suppose one disadvantage is the diagnostics in Triconex PLC is not good as compared to say Modicon......

Kindly guide

Regards

RAVI
 
S
You cannot simply say that one plc is better than anouther. It all depends on the system requirements such as communication, degree of fault tolerance, math capability, Remote I/O needs, programming ease, local support, product certifications/listings, cost, backwards support of legacy products, etc.

I think that most would agree that Triconics makes the most fault tolerant system, but you would most likely get an arguement from many if you were to claim that it is the best at any of the other items list above, or many others not listed.

Ultimately, Triconics, Modicon, Allen-Bradley, Seimens, and the other larger manufactures all offer good products, and selecting one can be a difficult task but should be based on how well the product fits your specific needs.

Keep in mind that triconics probably has the most fault tolerant system, but if you are not going to provide redundant power sources, etc. then you just wasted your money for something you did not need! Evaluate the entire solution, and choose the appropriate solution and products!
 
L

Leonard Hamilton

Ravi
Each Safety Shutdown system requires a level of Risk Reduction which corresponds to the hazard involved. After a Safety Integrity Level is determined for a given situation, equipment and procdures must be chosen that will yield the required reliability. Since Triconex, Honeywell FSC, and possibly APACS and GE GMR, are designed to be fail safe, they will usually meet the requirements.
Nearly every PLC manufacturer's products are so durable they become obsolescent before they need to be replaced. Fail Safe PLCs are not always needed but may used because they connect to a Honeywell DCS, or because a good Reliability study is not cheap, or even to make a show of good faith. If you will need to make decisions about safety systems you should learn about Reliability and Safety Codes such as NFPA. Then you will be more able to discern between mere advertising and useful information.
Good Luck
Leonard
 
J

Johnny Mnemonic

Well, one thing that was not mentioned is the fact that triconex has triplicated Processors,
I\O, and power supplies. Something that A/b or modicon doesn't have. Triplex is another triplicated system (which I prefer). And
thats why you have a Triconex on your safety
system.

Johnny Mnemonic
 
A
One more note:

Mention of Fault tolerance in the original mail:

Though conventionally, we use the term fault tolerant for redundant systems, fault tolerance and redundancy are two different things.

Fault tolerance involves your engineering too and is a limited definition, where u have to specify the faults that can be tolerated and to what extent this fault will be tolerated. Viz voltage upto say 500 KV and so on.

Redundant systems are fault tolerant to the extent of internal system failures. If your engineering is not upto the mark, then your total system may not be fault tolerant. And even TMR may not help you. While with good engineering even a simple PLC may function properly.

Regards,
Anand
 
A

Asif Khokher

RAVI,

Well! I disagree with you that that TRICONEX has got less diagnostic capabilities than othe PLCs i.e MODICON. Infact, it is the diagnostic also
which makes it SIL3 suitable hardware. SIL is Safety Integrity Level, which is specified for a plant before the develpoment of Safety System
Specifications. AB and MODICON's no PLC is SIL3 certified. TRICONEX is TUV certified for SIL ratings.

It is not the MONEY which decides, it is the INTEGRITY and AVAILABILITY reqiured which defines the specifications. One thing more; If TRICONEX is
not used in a recommended architecture than YES it is waistage of Money upto some limit.

Asif Khokher
 
B

Bob Peterson

In the real world, these terms are used much as the term "open" is. They mean whatever the marketing wizard that said it thinks it means. I doubt that you could get any group of engineers to agree what these terms mean other then the term redundant obviously means that there are multiple devices capable of performing a specific function.
 
Anand,

Engineering is not upto the mark -
Good Engineering -
I'm sorry, I feel these two statements are misleading.

I got what you mean. But with in the context PLC's capability and performance should be measurable.

That's why they (Triconex) are certified for the safety integrity levels against the required.

In case of your simple PLC their characteristics or their performance are unpredictable and we can not even force it to behave as we required.

These are the fundamental differences.
 
RAVI

ProSafe-RS safety system from YOKOGAWA is TUV Approved and it has more system avaliablty,and much more diagnostics then Triconex.

Triconex is voting system with 3CPU and 3 I/O.
if any one I/O fails with this three one whole leg will fail,
if u see clearly Triconex TMR architecture
voter is presented in output ckt

just think
all three are in one module what is the PFD of that module and common couse error of the ckt.

i am not blaming that system. TMR was good in past days with old technologies.

but nowadays techologiies are improved,
but Triconex is not improving their design.

u cant say which is best PLC in market, based on application only they are different for each other

some of other ESD system avaliable in market
with SIL3 TUV certification

Yokogawa is supplying ESD system with *Pair and spare architecture*

ABB and ICS Triplex supplying ESD system with *same TMR architecture*

AB is 1oo2D
Honeywell and HIMA is QMR.

regards
Manikandan
 
I have used many PLCs and many safety PLCs (SIS) in the past. None come close to Triconex Tricon, so far.

Even many engineers from major DCS company (Honeywell, Emerson, Yokogawa) would still agree that Triconex is still the easiest and the most robust safety PLC in the market.

James T
 
Manikandan,

Can you please let me know what are the factors involved in calculating the PFD factor for PLC systems?
 
S
James,

You really need to look at the RTP 2500 SIS.
TUV approved SIL 3
2600 years MTTFS
99.99999 availability
10 year simple proof test interval
Extensive Diagnostics
TMR with Controllers in the same chassis, or in separate chassis.
Full DCS Software Suite.
 
Triconex ESD system practicaly proved popular system in oil/gas/petrochemical process industries.

Triconex hardware part its no issues as per used plants history like Exp (saudi aramco, Sabic, QGPC, ADNOC and etc). and software part also its use and friendly.

Simple network and Interfacing to other systems.

Regards
venkat
CGC. WLL
Doha- Qatar
 
Hi,

I've just joined this forum and this my first take on the topic. Vendors use different architectures to arrive at a certain measurable risk reduction factor. If a Honeywell QMR system is SIL3 and a Triconex TMR system is also SIL3 then should we be worrying about the difference in architectures? Or there's more to it than mere certification?

Nirlep
 
ICS Triplex provide TMR ESD System Trusted, which is better in terms of technology over Triconex. Trusted is having design of fault tolerance through hardware. Fault can be contained and allow system to run.

Trusted is easy to configure and having strong diagnostic.

Ajay
 
RTP 2500 system is the real next generation technology. We saw the demo done by the Indian subsidiary of RTP recently of RTP 2500 system and believe me the system technology is mind boggling. It has built in Proof Test software, unlimited online downloads, unlimited configuration changes, PFD average value is excellent, the HMI package called NetSuite software is a site license - meaning one time purchase by the end customer, unlimited tags, OPC, Historian, Archiving built in - all SIL certified, all inputs to be SOE time stamped, node processors can be separated at 12Kms distance and 25msec reaction time. Hats off to the inventor - a genius system unparalleled to date.
 
I am not familiar with Triconex but I have used ICS Triplex, they may be great for safety shutdown but you would never use one for normal logic. A regular PLC like AB or Modicon is much easier to wire and has better engineering tools for normal logic.

Roy
 
N
Manikandan,

You absolutely correct. Triplicated systems need to vote everything 2oo3 in order to meet the required PFD for SIL3. Smarter diagnostic based systems simply don't need to do this to meet SIL3. Your simply paying for hardware you don't need with TMR solutions. Check out the HIMAX system if you want to see where technology is currently up to.
 
Ajay,

It is obvious that you have not examined the voter circuit on a Tricon DO. The switches are Darlington pair transistors. The last time I checked, that's considered hardware. "Better in terms of technology" please justify your opinion with more information. Better how?
 
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