What is the Difference Between PLC and DCS?

Why does it seem like India uses the DCS system more?

How Output ON From TON Timer And OFF From Counter What Will Be The Logic??? I am Using S7-200 PLC

You guys must have never met a conputer expert. That's a distributed system duh

DCS has a master controller with several slaves networked together so that the master resolves the control logic and the slaves perform it. PLCs are not same as DCS not even today.
PLC is controller
DCS is network of controllers
and SCADA is software

Light and photocell work quieter than relay

I am taking a mechatronics class and the teacher uses a lot of your videos. I always love them because it’s a break from the lectures.

Can we connect PH and RH detecter sensor in on display or transmitter?

Thank you very much.

Excelent!

Really good education

The animations of your videos are impressive

Great video. In addition to the architecture explained in the video there is a bit more that shows each's benefit.
In a DCS, it is extremely tough to program/maintain/trouble a sequential process (especially the ice cream example used). A DCS is better in a continuous process such a refinery where, for example, oil/gas is always flowing in out of the process. Pumps/valves rarely stop/close except during outages. This is because of the programming of function block diagrams. There is little to no need to dig into a function block diagram to see the code in a continuous process.
A PLC is handled better for sequential processes. Being able to see all ladder logic helps to program/maintain/troubleshoot this process. If you used nothing but function blocks and AOIs, and a line went down, it would be tough to troubleshoot. You could have a hard time finding out what is causing an output from being energized. It could be power, a valve stuck in manual, or bit that got tripped up.

What a dick he wants to work on Saturday 🤣

What is the R-control Ei800.. It used for control drive servo motor

Interesting for repetitive production.

Awesome video for best learn, I am interested for pro pack

You could also add that a PLC system can execute the logic at a much faster rate than the DCS does. Great video!

👍

I like that.

Great video

perfect

Very good. I keep dipping my toes into learning more about PLCs as I think that they offer real advantages to what we do, but somehow haven’t taken enough steps to gain the confidence I need

I wish u put Arabic translation in the video
Anyway thanks

Very good! The PLC is usually used for Basic Control Process Systems and the DCS for Safety Systems or there is not this relation?

please make videos on scada tutorial

Can i connect the dcs end cable with two pcs have same application control and monitoring

Besten Dank (Y)

Your channel rocks

Good presentation sir. Always following your videos.

Good

Ladder Logic, AS, FU, that is really outdated, maybe try a video about modern systems. Siemens isn't really up to par with for example Beckhoff. Its like teaching COBOL to students while they should learn C or Python. At least mentioning Structured Text would give this video more credibility. The TwinCAT System is what you should be looking for when talking about modern PLC Systems. For years now there are OOP extensions which make PLC programming even more scalable and in addition to that C++ can be incorporated natively.

There is no use teaching students that old stuff. This can be picked up along the way when the foundations of modern systems are thaught.
Learning C should be mandatory for all programmers.

Great idea 💡

Sorry folks this video is for numpties and does not explain the difference between a DCS and a PLC at all. I have worked for Honeywell, ABB, Siemens and Rockwell and started my career at the beginning of the modern control system era in the early 80s.

The difference is nothing to do with what this system explains.


Networking. A DCS allows dual network redundancy. A PLC does not.

Programming. The DCS allows a better CPU for programming abalog control. But modern PLCs are getting better at this.

A proper DCS allows hot swapping of IO modules without power down
. A PLC generally does not but this is changing with networked IO

Modern DCSs are now allowing control of multiple programmers on the system. Even to the same CPU.

A modern DCS allows integration of shared memory between HMI and CPU. Siemens TIA however now removes that distinction.

Back plane. A DCS allows potentially the programming of intelligent devices through it and across it. But Rockwell allow this for a long time. Eg. Devicenet.

DCS are over priced and hyped. Delta V is popular because it has mastered S88 whereas Rockwell is catching up and Siemens PCS is shockingly clumsy.

What is the name of the controllers used in dcs? Are they plcs or have another name?

good good

Simple explaination and comparison. Why dont you start showing the process of programming it from the beginning until the end on a certain equipment . Hope those effort will help thousand of people out there who had lost or currently thinking to create a new project or remodify something for a better purpose.

I always appreciate real parts video. Can you please give me Training about scada of Siemens.

Your videos are very precious for us!

Very nice comparison... Good work dear real Team

Dear Realpars, Can you teach BAS?

Working in controls this is what we consider a DCS system.


Data collection system (DCS) is a computer application that facilitates the process of data collection, allowing specific, structured information to be gathered in a systematic fashion, subsequently enabling data analysis to be performed on the information.

Very simple and excellent way of explanation. Thank you

You should point out that today there are companies out there that provide the best of both worlds, such as Schneider Electric (Modicon) with their EcoStruxure Hybrid DCS solution. This provides the single database, single configuration, unified operator interface of a DCS along with the openness, scaleability and flexibility of a distributed PLC system. On top of that EcoStruxure Hybrid DCS also provides powerful run-time navigation services and support of redundant (hot standby) architectures. By the way, the name MODICON comes from MOdular DIgital CONtroller :-)

Please make video on 800XA DCS with redundant AC 800M and it's I/o's. Specially Wiring

Great series from what I've seen so far and I'm thinking of sharing this with my non-I&C clients so that they have a better appreciation for what it is they're paying for and why we seem to ask a million questions when they ask for quotes :)

One thing about the DCS is that historically, it was an evolution of traditional process automation, that is, everything that wasn't covered by relay logic, and it didn't just "invent itself" from trying to find something that's traditionally recognised a computer (i.e. a beige box or mainframe) would do.

I realise that following that the following history would have taken the video off on a tangent and possibly lost some people but for the benefit of those who may be wondering "so what was before DCSs", here's some context for you ;)

Whereas relay logic was predominantly the domain of sequential switching control, i.e. motor and solenoid on-off control, traditional process control - variable control - started back at the turn of the 20th century with mechanical controls. This evolved through the '40s and '50s into pneumatic controls with more complex mathematical functions, transitioning into analog electronic equivalents. All of these required external analogue computers to perform additional simple mathematic functions such as square root, addition, subtraction, multiplication, division, high-low select, and so on.

When microprocessors hit the scene, initially these were employed predominantly in early DCSs due to cost. Whilst Distributed Control System is a clever marketing term, in brown-fields plants, these microprocessor-based controllers effectively replaced the area instrument panels ( a collection of single loop controllers and indicators), so in a sense, it could be countered that they actually integrated more than distributed process control. Controllers still existed in the same physical plant locations in most cases, but the control room could now be centralised - that was the kicker.
Meanwhile, for the end-users who could not justify the expense of a DCS, microprocessors made their way into single-loop panel mount controllers, which initially didn't allow much in the way of user functionality over the analogue and discrete digital electronic version which they replaced.

But when users had access to programmable microprocessor-based controllers, that's when configuration/programming of microprocessor-based single loop controllers really shone. As with the DCS, it was now possible to bring in up to four analog inputs and perform the mathematics which once required additional external devices. Complex control was becoming cheaper but you still needed panel space.
Eventually, communications pathways were developed so that such single-loop controllers could be integrated with PLCs or DCSs and presented to the operator as a homogenous control system which was more DCS like than PLC. The falling cost of DCSs and PLCs - the latter in particular - has pretty much seen the single-loop controller relegated to simple local control panel duties in vendor equipment or commercial applications.

Generally speaking, DCSs and PLCs (SCADA is effectively a PLC with telemetry tacked onto it) can do the job of each other in general applications but you'll see more PLCs in operation than DCSs for a reason and it's not because they're necessarily better, it's more about the application.

For heavily sequential operations such as an assembly line or a mine-site, a PLC is cost-effective as it's fundamental design focus is high-speed switching with minimal complex computational functionality.
For critical complex process automation (chemical, petrochem, etc.) the DCS remains the BPCS (Basic Programmable Control System) of choice since the design focus is on performing complex mathematical computations for a multitude of interactive complex control functions at high-speed.
I wouldn't choose a PLC to control a mineral or petrochem facility, but likewise, I wouldn't select a DCS (purely on cost and wasted functionality) for a mine-to-shipping operation.

Can multiple PLCs be combined to form DCS ?

Question : is it possible for one controller to communicate with the other one in the DCS ?


: Is it possible for one HMI to control more then one controller in any of the system