Step 2: Building the AC module

CAUTION ! Never work on a live circuit.  Carefully route and insulate all wiring.

The AC module consists of a six way AC receptacle that has been modified with a Hall effect sensor mounted on two of the six available receptacles. Any current draw of more than 4 amps produces a 5VDC, 60 Hz square wave that can be read by the master module.  Cut a small break in the neutral lead of the two receptacle neutral wires that you want to use for the washer and dryer.  Cut a quarter inch iron bolt to about a half inch length.  Wrap  about 6 turns of #14 enameled copper wire around the bolt and solder the ends to each end of the break in the receptacle neutral.  Glue the hall switch with to the end of the bolt with the beveled side toward the bolt.  Solder the resistor between the outside leads of the hall switch.  See schematic and photo for details.  Make sure all wiring is separated and insulated properly.

The Hall switch also provides complete isolation from AC line voltages.
<p>Being very hearing impaired myself I am always looking for concepts that will assist, so appreciate your invention. That said, some day hopefully someone will come up with a hand held device (similar to a cell phone) that will translate audio into script as find even the best hearing aid devices don't necessarily deliver clarity when in certain environments which in turn can be frustrating for both parties involved in a conversation.</p>
Great job!!! <br> <br>A quick couple of questions... <br> <br> <br>What about people who have a 220v dryer? Instead of using a plug like you have, could we simply open the washer/dryer (at least the older units with the dial timers) and find 120vac on it, then attach a cord to it to bring it outside the case and attach your hall effect sensor? <br> <br>Thanks
110 V or 220V should not make any difference to the hall switch. It is the magnetic field that operates the switch.<br><br>I would strongly recommend that you have someone look over your plans before proceeding. I would also recommend that you keep all high voltages and the sensor within the appliance and only bring out the signal lines from the hall sensor.<br><br>Good luck on your build!
<p>I agree with yr safety advice. If the Hall sensor gives a 5V signal, one could consider feeding it to an optocoupler even, just to get a double isolation. Some of those wires in the AC box are rather close :-)</p>
I'm thinking I may stick with your design mostly except I'll use an or one rbbb for my washer and one for my dryer. <br> <br>I still don,t know about the hall effect. I may even think about attaching an led to the dial timer with a 5v adapter and using a photocell or one of these <br>http://shop.moderndevice.com/products/ambi-light-sensor <br> to detect when the led is on. <br>
<p>Great project, interesting, especially measuring the current<br>I was just wondering, in your situation wouldnt a cooking alarm set to the time the washer needs not have been a quicker and simpler solution? Obviously she would have to carry the alarm with her to feel the vibrations</p>
<p>Great project, interesting, especially measuring the current<br>I was just wondering, in your situation wouldnt a cooking alarm set to the time the washer needs not have been a quicker and simpler solution?</p>
can I modify this to light up to different light for each? <br> <br>you have do5 as the light trigger now. Could that be set for the washer and the do4 be set for the washer?
Yes, you can have the code control LEDs on various pins, just be sure that you use a current limiting resistor. <br> <br>If you send me your email address, I will send you my code. You do not have to use a separate MCU for the washer and dryer. I suggest you start with the dryer since dryers typically stay on from start to finish. Washers tend to have periods in their cycles (that vary in number and length) which can give a false &quot;off&quot; signal. These periods can be accounted for in software.
or could you help me strip the code to just look for one machine and I'll build one foe each.
&quot;Main&quot; photos added per your request. Please let me know if this is acceptable and if this instructable is entered in the Arduino Challenge

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Bio: retired mechanical engineer
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