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Posted By: Surfinsparky Riddle me this - 09/19/06 08:50 PM
I got a call today from an office saying that when the lady turned her small desk fan on and off her electric stapler went off.Well I went over and thought she was drunk.Low and behold she was right well three dozen staples later I still cannot figure why this was happening.Testing the outlet everything appears normal to me anyway.Maybe the light sensor in the stapler is dirty or a momentary voltage drop in the circuit is doing it.Surely someone has ran across this.
Posted By: JoeTestingEngr Re: Riddle me this - 09/19/06 10:34 PM
I would expect that the paper sensor in the stapler feeds a high impedance input and that the fan is radiating a little noise. Did you try repositioning the fan and stapler with respect to each other? Is it only when the fan is turned on or off, or while it is running? This sounds like something that would be fixed with proper lead dress or perhaps a small RF bypass capacitor.
Joe
Posted By: Surfinsparky Re: Riddle me this - 09/19/06 11:50 PM
The fan and stapler were in the same outlet.Both at opposite ends of the cord lenghts.It would only happen when the fan speeds were changed or turning on.Of course you hate to stand there and look stupid but hey it happens in this trade.
Posted By: Dave T Re: Riddle me this - 09/19/06 11:57 PM
How does she turn 'ON' the staplein the first place? Is there is an actual on/off switch or membrain type push button? If the latter should the fan cause the voltage to drop enough it may cause to stapler to go to the off mode which would require the ON button to be pressed again similar to a motor starter.
Posted By: e57 Re: Riddle me this - 09/20/06 12:14 AM
Once went to a service call for an intermitant light and it took a while to realize it, but two neighbors had X-10 and no filters..... Only came out in conversation that her neighbor installed them. Hmmmm....

But your thing there.... Not knowing what or how the stapler operates it would be hard to guess from this side of my computer. But would say some type of electrical noise from the fan. Simular types of things happen that trip AFCI's.
Posted By: Rewired Re: Riddle me this - 09/20/06 09:38 PM
Bizarre as it sounds I had a similar problem only involving a hair dryer and a smoke alarm... Turning on the hair dryer caused the smoke alarm nearest the bathroom to sound and ONLY that detector ( were 4 or 5 interconnected). Plugging the dryer in any other outlet everything was normal, as was another hair dryer in the
"troubled" outlet. Never could figure out what was going on!
A.D
Posted By: Surfinsparky Re: Riddle me this - 09/20/06 11:59 PM
The stapler is always on.It uses a light sensor I think.What is an x-10?
Posted By: jraef Re: Riddle me this - 09/21/06 01:27 AM
The stapler uses a small opto sensor, normally triggered by the paper being inserted and blocking the sensor, to fire off an interposing SCR that powers the plunger solenoid. SCRs can be self-commutated (turned on without a trigger) if there is a rapid change in voltage on the line, called dv/dt (delta voltage / delta time), otherwise known as a "spike". Switching the motor on or changing speeds produces enough of a dv/dt spike to fire the SCR on the stapler. If they were plugged into different outlets, the added impedance of the wire would dampen the spike and not cause the stapler to self-fire. Tell her to move the fan or stapler, or just live with it, it isn't a real problem, just a curiosity. If she insists, take apart the stapler and put in a little RC snubber on the line coming in, about 1kohm and 1mf should do it. The snubber will get warm though.
Posted By: e57 Re: Riddle me this - 09/21/06 06:21 AM
Sounds like a decent explaination..... (Re:jraef)

Surfinsparky, X-10 is a power line carrier protocal used for a type of automation for dimmers and switching that was popular once. Although it has bee around for some time, it still continues to develope. (Rather slowly) By inserting some data (noise) on the line signals can be sent from on device to another. In the case I mentioned items in two different homes had the same address. With no filter between them, if the guy nextdoor turned on his living room light, the light of the customer would turn on. http://www.smarthome.com/remote_entire_home.html
Posted By: skipr Re: Riddle me this - 09/21/06 08:07 PM
This kind of reminds me of the time I was trying to fix a friends VCR. It worked in every other outlet except one, evrything else I plugged into the non working outlet worked. I found that if I moved the plant that was right next to Vcr, it would play, If put back the plant, VCR would not play. I tested the thoery 20 times and it was confirmed 100%. Explain that one!
Posted By: LarryC Re: Riddle me this - 09/21/06 10:57 PM
Quote
I found that if I moved the plant that was right next to VCR, it would play, If put back the plant, VCR would not play.

The plant was blocking the IR signal from the remote control.

Larry
Posted By: Surfinsparky Re: Riddle me this - 09/22/06 01:01 AM
Now that was funny!



[This message has been edited by Surfinsparky (edited 09-21-2006).]
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