Performance of the System.

I'm not sure what you mean.

If you're talking about an controller, you can gauge it's performance by checking how well it's keeping the process close to the setpoint.

If you're talking about an instrument, say a flowmeter, you can try to determine how accurate it is by a calibration check.

State your question clearly and we can give you better answers.

Sir ;

I agree what you said , but interms of DCS if we say the person has to comment about the performance of that system .

1) the controlling .

2) the data aqucasition .

3) response .

how a individual can account all the above terms .

thanks .

Okay, it's a little clearer now.

There are several ways to gauge the performance of a control system:

• speed - this can be speed of response, speed of calculation, speed of scanning, and clock speed. There may be more but these are top of the head.
• amount of memory - this determines how large your programs can be. Large memories can mean that your system can handle lots of data or can control large processes.
• operating system - I'm not talking about whether it's XP or 2000 or MacOS. A simple operating system can probably handle simple logic (AND, OR, XOR, NOT, and timer and counters). A more advanced system can incorporate instructions like SIN, COS, TAN, LOG, CMP (compare), etc.
• number of inputs/outputs - personally, I think the more the merrier. I've lost count of how many times we've had to upgrade our systems because we've run out of inputs or outputs.

Some of these actually qualify as specifications but they can also be used for comparing performance.

I seem to guess what you are saying.

your start point is not right. everyone has its benefit. it depends on where you work and your objects.

you can use eiher of them. to reach your goal.