SCADA help needed!

While I know that SCADA is an acronym for supervisory control and data acquisition, what does this include? Is this a set PLC communication language or could a dry contact from a system (close indicating no alarm and open indicating alarm) be considered SCADA?

A customer has requested SCADA from our control panel. We allready have automatic function were they can control system via them sending a permissive run contact as well as the alarm dry contact stated above. Do I need to add something??

SCADA help, maybe?

Try here. This site may help you with your quest.

SCADA covers a multitutde of sins, but I think a couple of dry contacts is stretching it a little too far!

As a general rule, when a customer requests a SCADA connection to a SCADA system, I interpret that to mean I have to provide a communications port that they can tie to their SCADA system, plus a list of data registers that they will read from and write to.

When a customer requests a SCADA system , I interpret it to mean they want a PC, graphic operator interface software, screens configured for data display, and a communications link to the filed I/O or PLCs or whatever.

You had better get a precise definition of what they want, and what you proposed.

SCADA is a PC-based program, not a function that a PLC can produce (although I HAVE seen some PLCs with PC modules, and a SCADA program running there).

Exact definitions vary. Some people call it a SCADA when it is nothing more than a PC-based HMI (focussing more on the "Supervisory Control" aspect). Others don't consider it a SCADA until it's talking with a database (focusing on "Data Acquisition").

It's not a set PLC language. Typically it consists of several components. There's a communication driver for getting data into/out of the PLC. Then there's a database of "tags", symbols that read a single or a bank of registers. There are usually graphics, and each object on the screen is linked to one or more tags. There will also be a canned alarming module, which can monitor many points (discrete or analog) and alart the supervisor/operator when an alarm condition has occurred. There is usually a trending capability, both real-time and historical (which means that the program has stored the history of the monitored point in a database somewhere).

There are all sorts of other bells and whistles that the SCADA manufacturers add on, but those are usually the essentials.

No, a dry contact is not a SCADA.

Thanks for the information, I understand much better now.