Is an active or passive
system more preferable?
Because active and passive control are the only two types of system you can choose from, it's best to know the main differences between the two.
To decide if an active or passive system would suit your needs best is quite easy to see. In fact I can say, almost without any doubt, the passive system is pretty much what most people would be opting for!
Ok how can I make that bold statement?
Well, the first big difference between the two system types can be seen in the price tag. Hmmm, that's put your brakes on already hasn't it! . . .
The big ol' reason for this is there is a lot more to the software and hardware with an active system as opposed to the humble passive system.
The passive system (which this site is concentrating on), just listens to what's going on with all the machines connected to the system. Then takes what it has heard and reports the information to the host display computer.
This information is then worked on to find any other data that can be worked out from what's been sent. Then all the data with perhaps some other things like machine ID's, is displayed in a nice layout on the monitor screen for easy viewing.
The listening area is called the passive range of motion and can be quite wide. This is made possible by a passive repeater or passive repeater cell. The passive range of motion is the area covered by all the machines within the system.
The passive repeater or passive repeater cell is used to expand the passive range of motion beyond the normal limits of a system. The limits that is imposed usually by more physical restraints such as wire length or buildings etc rather than the software side of things.
However an active-exchange (active x) system is able to control any or all of the machines connected to it from the remote viewer location. The flow of information would be very similar to the displaying computer but this information flow would/could now be carrying machine operation commands back to any of the machines connected to the active x system.
This is a function generally used with fully automated production lines that have to have all the safety guarding in place to allow the remote starting of machinery. But is used for area's needed to be kept clear of personel for other hazards like bio, heat or radiation.
I bet you can see this is not a cheap thing to do, which is why I'm not going to spend a great deal of time on covering it. As you will probably realise, there's going to be lot more hardware and software involved due to this two-way operational communication that is possible with this type of system.
A hard wired fail safe emergency stop circuit has to be installed with stop buttons at all key points (depending on hazard use) on all the machines involved to start with. As such these systems tend to be completely custom builds as a dedicated control system. All of this of course integrated within a machine information system.
The need for this type of system is few and far between these days. This mostly down to current safety requirements within a work place making this type of system more and more expensive to implement.
If fact the cost of an active x system goes a long way to justify if you need a system of this type. Because it does make quite a difference to how much of the folding stuff you would have shell out right at the start.
Let me also add here that an active system can also be referred to as an active x system, as I have ealier. This could possibly be where the computer term came from, but I'm only guessing here! (I'll have to look it up now)
I say that because this type of system has been around pretty much since simple electrical/electronics control systems have been in use.
Granted, in a far less evolved form.
I have even heard the term 'active sync download' used to describe the very same system except with the active sync download there is syncronised command/data exchange, I really don't mind what they are called. So by all means use whichever name you like according to your preference, which side of the water you are, sort of thing.
However I will say whatever you like to call them, I would advise you to steer away from this active x type of system unless you really really feel and justify you need one. Mainy from the safety aspect side of things, but also because so many machines can be involved, reliability as well. The reliability of a system (any system) to perform concerns me quite alot, after all what's the good of an 'up to the minute' information system that's having a snooze.
My apologies if you feel you want or have an active x system of this type and would like to know more about the control side of it. But I feel this falls outside the scope of the theme on this web site. I would not want to partially answer your questions or enquires by being too diverse. So forgive me but that's about all I'm going say on active machine information systems.
Please continue back on the Software page with finding out more on the passive information systems within the growing pages here.
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