Does anybody know...

floppybootstomp

floppybootstomp

sugar 'n spikes
Moderator
Joined
Mar 5, 2002
Messages
20,281
Reaction score
1,794
...where I could get a system to do this.

Basically it's trip nine switches remotely through a computer network to be triggered via a timer device or a timer integral to some software.

Here's the setup:

Nine buildings forming one secondary school site all connected via a common computer network.

Each building has a series of fire alarm bells which as well as providing a continuous signal for the fire alarm also act as a sounder device for signalling class change times with a short burst of signal. This signal is possibly pulsed to distinguish it from the continuous fire alarm signal.

Currently each of the nine sets of bells are triggered for class change with a clock local to them that simply provides a short circuit at programmed times. The short circuit switches one pole of 24 volts DC to the bells, making them sound. I'm familiar with the timer clocks and know they can supply a continuous or pulsed signal for between 1 and 10 seconds, both functions are set through dip switches internally.

But these clocks are rather old and a few weeks after resetting all nine, they all go out of sync with each other.

What I want to do is have one central timer which operates a mechanical switch via the computer network at each of those nine locations thus synchronising all nine sites. I would assume there would be software from a central computer sending timed signals to operate an interface at each location.

Doable? Does such a thing exist?
 
http://www.arduino.cc/

"Arduino can sense the environment by receiving input from a variety of sensors and can affect its surroundings by controlling lights, motors, and other actuators. The microcontroller on the board is programmed using the Arduino programming language (based on Wiring) and the Arduino development environment (based on Processing). Arduino projects can be stand-alone or they can communicate with software on running on a computer (e.g. Flash, Processing, MaxMSP). "

:cool:
 
TXD: yep, that would certainly do the mechanical interface but do computers still have paralell ports?

Abarb: Totally off the mark mon ami, one doesn't seem to have grasped the concept ;)

I've been doing a little research and thinking and software exists to do this thing, it's quite common in fact.

The more I think about it for it to be controlled through a network a workstation would probably have to be present at each of the nine locations and they will have to be switched on and off each day or left on 24/7. Which to my mind seems impractical.

Although as the workstation only has one very simple function to carry out any old machine would do and some of this software available runs on Linux, which would keep the cost down. Although the school probably has a huge Microsoft licence anyway, most schools do in London.

To my mind a much more solid arrangement would be to hard wire all nine sites together and operate the whole system from a single timer clock. However, I haven't been to this school for around ten years and I can't remember how far apart the buildings are but if they've laid network cable then it's possible ducting may be in place with, hopefully, draw-cords left in.

I do recall one building is on the opposite side of the road to the main building but it's in a cul-de-sac so shouldn't be too much of a problem digging a trench.

I will probably visit the site next week.

Thanks for the input so far :)
 
Erm yes a lot of systems still do mate as far as i'm aware

You could always ask the school that wants the system fitted if their control pc has a parallel port at rear?

It reads a very big job mate?
 
TriplexDread said:
Erm yes a lot of systems still do mate as far as i'm aware

You could always ask the school that wants the system fitted if their control pc has a parallel port at rear?
Click to expand...

Yes, as I mentioned above, they probably have quite a few old machines which will certainly have paralell ports.

The premises manager wants this thing, he discussed it with the IT guy and the IT guy phoned me so it's natural the IT fella would seek a networked solution. I suspect it's because he realises it's the only common cable between nine sites.

It may be a good idea but I still suspect a more simplistic approach (hard-wiring) may be more economical and more reliable.
 
Yeah you may be right

The IT guy wants teh 8core in to make things easier for him I guess? lol

But as long as they pay you the cash you quote em mate who's to argue? :)
 
if they have the money to splash then you could use some snap I/O's from opto22, not cheap but can be controlled over ethernet

http://www.opto22.com/site/pcbasedio.aspx

Edit: should mention that its all on one rack mountable rail from which you'd need to run cables to the various buildings
 
floppybootstomp said:
The more I think about it for it to be controlled through a network a workstation would probably have to be present at each of the nine locations and they will have to be switched on and off each day or left on 24/7. Which to my mind seems impractical.
Click to expand...

You could always go for one machine running 9 virtual machines.
 
Me__2001 said:
if they have the money to splash then you could use some snap I/O's from opto22, not cheap but can be controlled over ethernet

http://www.opto22.com/site/pcbasedio.aspx

Edit: should mention that its all on one rack mountable rail from which you'd need to run cables to the various buildings
Click to expand...

If cable was going to be run it may as well be just plain old 2-core to switch voltage/sound bells at each location. Which if it were practical is probably the simplest and cheapest solution.

But as I said I don't know the layout of the buildings yet so it may be impractical.

The IT fella's idea is, is that as a network is in place perhaps it can be used for central, synchronised switching.
 
EvanDavis said:
You could always go for one machine running 9 virtual machines.
Click to expand...

And just how does one machine running nine virtual machines mechanically switch at eight other locations then?

The computers are only being used as triggers via software to operate a simple SPST switch. It's a mechanical thing, a physical action, not a virtual situation.
 
Ok, just got back from the survey and here's the situation.

Cabling is impractical, because of the locations it would be very expensive to link all of them with cable, linking the two sites across the road for instance, would require hiring a cherry-picker and running a catinery between the two buildings.

It is in fact eight locations.

They will supply all the network sockets at each location and eight licensed copies of Windows OS.

I am to supply eight computers, eight mechanical switches, software and then program and connect each computer to the class change switches.

I also have to remove the old clocks.

If anybody knows anything to suit I'd be grateful to hear from you.

Here we go then, source, source, source....
 
If you are going to have a PC in each location then it may be worth considering something similar to what TD suggested. You can get USB relay boards that can be controlled with VB scripts

http://www.sigma-shop.com/product/7/usb-relay-controller-one-channel.html

My friend has an eight channel version to control the pan/tilt function on his CCTV cam. He has a web page that displays the feed from the camera and controls the pan/tilt using buttons on the page. It should be possible to have a central page that all of them are controlled from
 
Me__2001 said:
If you are going to have a PC in each location then it may be worth considering something similar to what TD suggested. You can get USB relay boards that can be controlled with VB scripts

http://www.sigma-shop.com/product/7/usb-relay-controller-one-channel.html

My friend has an eight channel version to control the pan/tilt function on his CCTV cam. He has a web page that displays the feed from the camera and controls the pan/tilt using buttons on the page. It should be possible to have a central page that all of them are controlled from
Click to expand...

Thanks Me_2001 that may very well cover one part of the requirements, now have to check out available software to suit.

A fella at an American forum I frequent sent me a link to this software
http://www.acrovista.com/bellcommander/ which looks as if it would do the job but I have yet to find a UK supplier.

Thanks again :thumb:
 
I e-mailed the BellCommander company after noting this seemed to be ideal for my needs: Link

Yesterday I received a very courteous and helpful reply from a guy at the company who tells me their software and hardware will do the job, they can sell me the software as downloads and he's given me the number of a UK supplier who stocks their hardware.

That was... refreshing.

I'm still a little unclear on Network requirements, I need to do a little more research and studying but it's looking hopeful I'll be able to put a quotation together fairly soon.

It also looks as though only one central computer may be needed with relay devices plugged into the network at the other locations.
 
Back
Top