Upgrading voting system

We are presently looking to upgrade an old voting system which has a legacy software program, and uses mechanical switches. We would like to keep the switches (105 places, 3 momentary switches per place), replace the old logic reader hardware with PLC's, and program and read the PLC's with a Windows XP computer. The XP computer would then provide us the ability to turn the switch information into a format we could display on a computer screen in the form of changing the color of a name (105 names). The XP computer would also be able to take that switch information and send a packet of data to our data base for the vote total record. Does anyone have any recommendations on software for the reading of the outputs of the PLC registers?

Take a look at this thread:

http://www.plctalk.net/qanda/showthread.php?t=11030

I don't remember how serious it was but some ideas were tossed around here.

Keith

kamenges said:

I don't remember how serious it was but some ideas were tossed around here.

Click to expand...

I think that in the end, we decided that a PLC system might be too open to tampering.

I appreciate your response. Our application is fairly simple, and we'd like to solve it using PLC's or better yet a SoftPLC application. The votes we take have two outcomes in our system: First, we use the vote (Yea, Nay, Abstain) to indicate on big wall mounted member name display boards what the members vote was (changing color of each member name based on vote - Red-nay, green-yea, yellow-abstain). Second, we send the delimited vote total to an Oracle database to record. We would like to get away from proprietary software and just deal with a Windows environment. Also, what hardware interfaces are available to connect the existing switches (lighted momentary type) to the computer housing the SoftPLC software? Thanks for your input!

I think that earlier thread involved in voting for political office where this application is something like a committee of members voting on propositions etc all at one time. It is still possible to tamper with but would be more difficult since it is done all at once.

The issue as I see it is you would need 450 (or more) inputs and possibly 450 (or more) outputs, with SCADA capabilities. This could be costly.

What I see is a main computer with SCADA software offering a place to enter a number or name ...ie proposition A13. Someone would enter this number/name into a form and initiate the vote. The plc would count the votes only allowing one vote or no vote per place, either time the vote, stop the vote when all places have voted, or the "operator" would initiate VOTE STOP order with the SCADA software. The individual votes would directly change the color on the display. The votes, aye, nay, abstain, and no vote (no vote and abstain may not be the same thing) could easily be placed on a spreadsheet etc showing the totals...the name/number originally entered would be the name/number of this spreadsheet. The spreadsheet could do the tallies or the PLC could do the tallies and just enter the totals into the database...several options on this point.

Thanks for your reply. Yes, there would be a number of individual inputs, since there are 105 desks, with 5 mechanical switches per desk, and added to that, the switches (when voted) light up to indicate that member had voted. Do you know of a company that makes the wiring terminal blocks that could handle that number of inputs? Also, would this terminal be connectable to the PC through a fast bus, say firewire? Again, thanks for your input.

Bob I am not sure how your existing system is setup but I assume all the inputs (buttons pushed) go to one location.

One company is Automationdirect http://www.automationdirect.com that has several plcs that could easily accomodate the inputs in numerous ways. With the number of I/O needed I think you may have to use a DL205 or above. I can not offer all the details but the DL205 H2-EBC that can support Ethernet I/O and connection to a PC based controller.

The DL205 can handle more than the I/O count you have mentioned but just so you know the cpu, base and I/O will probably run around $5000, this does not include the PC and PC based control software that would be needed which could be another $3000 (guessing).

I suggest checking out their website, look at the PLCs and Server Software. After looking over the products give them a call and see what suggestions they can offer...good bunch of guys to deal with.

Just an FYI, there are companies that design and build these type systems. This is one: http://www.votingsystems.com/products.htm

FYI: I am in Birmingham (Tarrant) and may be able to assist if you are close enough. There also may be less expensive options I have not thought of at this time.

Thanks for the automationdirect info. I sent them a querry. Are you a PLC engineer? Didn't know if you were in the biz, or sales, or what. Again thanks for the help.

Bob,

With what has been discussed so far, what is your budget for something like this?

105 voting locations can be complex. One PLC with all the I/O will require a lot of wiring. So the cost of the controller will only be part of the cost you will need to consider.

In that you may be able to do this with one PLC, the wiring costs might be quite extensive.

One option to consider is a micro at each location networked to a host PC with an HMI front end.

There will be less wiring. You can find a controller with RS485 that will allow you a distance of up to 4000 feet...and it is only one cable. (rather than multiple wires) Each PLC will have the same program...but a different slave address...identifying each location (voter) so that the HMI can keep track and display the votes accordingly.

You could also use the outputs for indicators at the desk if you wanted to have a couple of lights that can be visually seen as to their status...seeing as you will have outputs left over. I have seen something like this in various parliment chambers.

Hope this helps.

God Bless,

I know this is PLC land but you may wish to investigate using individual data aquisition modules, one at each desk, reading the switches. The PC could read them directly with an appropriate RS485 converter module. Each will need a small DC power supply also. It would probably be more money overall but much more flexible. Check out B&B Electronics

Voting? That means there's a poll involved.... So, where's Casey?

Multiplexing could drastically reduce the number of inputs required. Since there is an indicator on the buttons, the voter gets confirmation that his/her vote was recieved. Therefore, it doesn't even even have to be high speed multiplexing.

Let's see, a mere 24 in and 24 out would yield 576 inputs...

Outputs could be multiplexed as well, though you'd want to do that at a higher speed. Unless, of course, you don't mind the confirmation lights blinking. On the other hand, blinking lights might look cool!...



-Eric

Stephen, thanks for the interest. Our chambers are already wired, all wires going to one location - a data closet. Our budget, well right now we are in the position of exploring several options, so as of today there is no talk of $$$$. We will most likely replace the LED displays on the walls with DLP projectors, thus the need to conform the output information to Windows based screens. We are working on an angle now to put touch screen PC's at each desk, all of them tied to a server. That option would run about $1500.00 per desk. The DLP projectors, we estimate, will cost about $250-$300K. So, the softPLC option would save us the cost of the individual PC's at each desk, about $160K. Thanks for any input you may have. I looked at your company's site, but didn't see any wiring blocks that could communicate with the PC.

Bernie, any particular model come to mind? Would these modules have to be addressed, as in IP addressed? I appreciate you thoughts.

The units take an address. I understand that there are now Eternet communicating modules. But, given that, as you pointed out in your recent post, all the wires are already in place and coming back to a central point it makes no sense to use these.

Eric, the present system is multiplexed, and is quite fast. Some members, when the voting machine is open for a vote, will press yea, then nay, then yea, then nay........just to keep everybody else guessing. The system now is very responsive. Speed is an issue with our current development direction, which is to put touchscreen PC's at every desk. We are writing directly to the member name wall display screens, changing the name colors. When the vote machine is closed, we go and read each members name position for color. That info, preceeded with some minor header info (Bill #, etc.) is turned into a text string which is sent up to the database and is the recorded vote. thank you for your interest.