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Looking for a tamper proof counter.

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jimllshiftit

New Member
Hi everybody. New on here and I hope you can help me.

I am not an electronics whizz by any stretch of the imagination but I am competent with a soldering iron and basic wiring projects.

I currently run a holiday rental business which requires constant monitoring of the usage of dishwashers and washing machines. Currently we do this by counting the number of dishwasher tablets and quantity of washing powder used but I could really do with something that the guest can see counting everytime the machine is turned on.

First of all i cant find a counter that would do this, where would I look for one? Secondly where would the counter be mounted? Ideally id like to be able to "hard wire" it into the flex coming from the wall socket. Would that work. A flashing LED would be useful aswell, just ot draw there attention to its monitoring.

Any help is greatly appreciated.
 

birdman0_o

Active Member
This isnt the easiest thing in the world but it can be straight forward, every time a washing machine is turned on advance a counter?

If you got into micro controllers you could have and LCD and then use the build in memory to store total usage for this guest and then total of every guest.

It might get complicated with just normal circuitry.

What is a "flex"?
 

gabeNC

Member
Electric wiring code out here states that you have to have a cutoff switch for the dishwasher. Normally I've seen them wired as a generic light switch. I bet you could put the guts into the same wiring enclosure box and have a seven-seg visible and maybe a small key lock switch tied into the reset (mclr) so you don't have to take the cover off to reset it.
I wonder if you would have to monitor the electrical load for a given length of time in case they shut it down quickly to load more? Wouldn't want to increment the counter if it really didn't run. *shrug*.
sound like an interesting project.
 

crutschow

Well-Known Member
Most Helpful Member
Alternately you could monitor the time it is on by monitoring the current. Knowing the time required for the average wash cycle, you could calculate the number of washes. That would eliminate the problem of getting an incorrect reading if they turn it off and on to reload more items into the machine or whatever.
 

jimllshiftit

New Member
By Flex I mean the cable that leads from the machine to the plug. I think thats a term I picked up while working I Spain , force of habit using it here.

Anyway thanks for the response. The counter wouldnt need to be reset. So long as the guest and I knew what the number was when they arrived we could simply take that away from the number read when they leaft. That would be good enough for this case.
 

mneary

New Member
I bought a device (you don't give a clue where you are) called a "Kill A Watt" which measures energy consumption over time. You can monitor the power consumed by the washers to double check the guest's memory.

Only big problem is that the $20 version of "Kill A Watt" resets when it loses power, but there is a battery supported version for more.
 

jimllshiftit

New Member
thanks mneary.

The trouble with the kill a watt is that it can be reset by the guest pretty easily, also it would be possibly for the guest to simply unplug the kill a watt a run the machine only to replace it afterwards.

What I need is the same sort of thing but more permanent which gives a straight reading of the amount of times it has been turned on.

Anyway where can I buy digital displays and stuff?
 
Hi

I'm thinking you want to measure the "time on" of the machines and count the duration of the time on.I know sometimes these work from coin operated switches - (one of many)
Coin / Token Operated Time Switch

Alternatively you can create something of your own.

I recently looked in to RF data transfer and I think you could adapt this to suit your needs.
Take a look at this demo-
XBee Configuration Tutorial - Tellart [stream]

You have an xbee with shield device on each machine and configure it to what information you want and then one in your office as a receiver.The one in your office can be much simpler as it's only receiving serial data and putting it in your PC. Each xbee will send the data to you through serial and the data can be stored automatically on your PC.

With a little imagination you could hook up some 7 seg. displays to the devices at each machine so the user can see.

Sounds very difficult but look at the demo and I'm sure it will be worth the effort.

Just brain storming.Hope it helps
 

tytower

Banned
Its probably more than you want to do but this guy watches his power all the time Home Monitoring System Details

Now until you get something useful put a small black plastic project box on the line (small holes cut in box to get the cable in and then screwed back up and sikaflex on top of the screws) . One from Jaycar or Tandy etc.

If you build in a little flashing LED that will serve to trouble them at the time of use and if its opened you can easily tell. Look at the link above and you can tell them thats whats in the box. Power monitoring stuff directly transmitted back to your computer. Bit of ******** goes a long way sometimes.
 

jimllshiftit

New Member
Tytower, that was my mark one design. My mark two was the same but with a dummy aerial coming out of it and my mark three was going to incorporate a counter, hence this post!! Great minds hey!!

Thanks for all the info, now i can begin to see if the mark three is feasable or whether I should just stick to mark two.
 

Diver300

Well-Known Member
Most Helpful Member

mneary

New Member
thanks mneary.

The trouble with the kill a watt is that it can be reset by the guest pretty easily, also it would be possibly for the guest to simply unplug the kill a watt a run the machine only to replace it afterwards.

What I need is the same sort of thing but more permanent which gives a straight reading of the amount of times it has been turned on.

Anyway where can I buy digital displays and stuff?
The guest can reset it if he can get to it. It's not large, so you should be able to lock a utility box around it, while it's plugged in. The box would have exit and entry openings that capture the power cords, and only allow removal when the door is open. You could have a clear cover like a common electric meter if you like.

I would certainly hope that most of the temptation to cheat would be removed by the simple fact that the renter knows you can check his story.

I know where I can buy digital displays and stuff, but I have no idea where you can buy them. This is a world wide forum and you have chosen not to put a clue as to your location in your UserCP.
 
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