'Hotwired' my fan - is this safe?

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TheNiceGuy

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Dec 23, 2004
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Hi all
We have a cheap floor fan that has a lot of gizmos on it that we never used, including remote control and digital readout. Something in the circuit board went, and it cuts out if you jostle the box. Anyway, I took it apart, and saw that the main fan mechanism had 5 wires coming out of it: red; black; white; grey; beige; blue.
The red and black ones seem to just loop into some black box and back into the motor. IIU the diagram correctly, connecting grey with one of the color (white, beige, blue) will give different speeds (although they probably don't work as such now as they looped into the circuit board which I disconnected). So I hooked the wall plug cord directly, white to white, and black to grey. You can see this in the first picture below. It works fine. IIUC, the diagram on the fan motor says 100v 60hz, which is what comes out of our wall. You can see this diagram in teh second picture below.
So my question is is this safe? It would likely be left running unattended all night. I don't want a fire/shock etc. Should I throw it out? Add an additional component?
???
I'm not running it until I find out.

"Sweltering in Japan"

http://i22.photobucket.com/albums/b334/excipio/IMG_0963.jpg

http://i22.photobucket.com/albums/b334/excipio/IMG_0962.jpg
 

Paperdoc

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Aug 17, 2006
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What's really needed here is someone who can read the Japanese names on the wiring diagram. On the left of the diagram see the capacitor labeled 6microFarads? That is the "black box" connected by black and red leads - no doubt that is what the labels on those wires say in the diagram. At the very bottom of the diagram to the right of the motor is an open box inserted into the line with a label "130C". That is a temperature limit switch built into the motor body to shut off power if it overheats. To its right is the lead that connects to the Neutral supply from the wall - probably the White line of your wall connection. So the question there is: what color does the label say at the lower right terminal on the diagram? That is the wire to connect your White supply.

Similarly, the three terminals above that are labeled H, M and L in English, presumably for High, Medium and Low fan speeds. Can't tell whether the Japanese symbols next to them are speed indications, or colors. Anyway your power line Hot (Black?) should go to the High terminal. Insulate the ends of the other two wires so they don't short out.

Alternatively if you get a switch that offers three positions plus Off, you could actually re-establish the ability to set the three speeds.
 

TheNiceGuy

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Dec 23, 2004
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I can read Japanese (poorly), took me a while with a dictionary, but I got the colors.
The bottom right one is Grey. Top left is Red. Bottom left Black. HML are White Blue Beige respectively.

I'm a bit confused. The "130 C" switch and "6microfarads" are basically the same thing for my purposes? How do I wire them in? or are they already?
Also, in the picture you can see how I hooked up the Wall Plug wires. White to white, and Black to grey. It worked OK.
BTW, I don't need a speed or power switch, just plug power is OK for us.
Thanks
 
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C1

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Feb 21, 2008
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Capacitors are often used to phase shift the internal motor field for start up.

The one thing I would check though, is to make sure that the fan chassis is not electrically hot. That is, when connecting a voltmeter between fan chassis (ie, anything metal on the outside of the fan system that can be humanly touched) and (house) supply ground, then there should be no deflection. In other words, ensure that polarity is such that the external chassis is at ground.

One of the functions of the controller might be to act as an intermediary to isolate the chassis.
 

imagoon

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Feb 19, 2003
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The picture is to fuzzy for me to read the kanji well but yes White ( 白 shiro ) is neutral and Grey (灰 灰色 haiiro) is 'power'.

It may not matter though as certain prefectures don't "code" the power.

AC power to white and gray = fan on high. Also the motor is 100 to 120V so you are not over volting it or anything. If you are handy you could just attach a 4 position twist switch to the white side and have the three speeds again.
 
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imagoon

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Feb 19, 2003
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It looks like the blackbox (capacitor) runs on it's own two wires (hard to tell from the pictures) current doesn't flow "through" a caps leads typically. Do the red and black wires come out of the motor?

Hard to tell from the pics but it looks like all 6 come out of the motor. If that is the case, white + grey = High, black + red = start capacitor (black box.)
 
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TheNiceGuy

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Dec 23, 2004
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Yes, they all come out of the motor. So no need to do anything other than hook up as I did?
 

Paperdoc

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Aug 17, 2006
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The capacitor is the black box you see beside the motor, and its red and black leads are already connected to some points inside the motor case. In fact, the Black (bottom left) must be connected to one side of the 130 C thermal switch. That switch is already wired and mounted INSIDE the fan case where you can't see it. Its other lead (bottom right) is the Grey one you see. You do NOT need to make any connections to these items.

In most circuits like this, the bottom right connection is supposed to go to the the power supply Neutral line, and the power supply Hot line goes to the motor winding. In this case with three possible motor winding connection points (for three speeds), the Hot lead is first sent through a 3-position switch on the original PC board, and that switch determines which of the three possible points gets the Hot lead connection. You are trying NOT to use that feature, and just run it at High speed all the time. That is the White lead, you say. Therefore, you actually have the two power supply leads backwards. The power supply white normally is Neutral in North America (not sure about in Japan), so it should connect to the grey lead from the motor. Likewise, Black in North America on the power cord should be Hot, and this motor has its white lead as the High speed input connection. It happens that you DO have the power supply lines connected to the correct points, just backwards. For an AC capacitor-start motor this will make no difference - it still will work as it is supposed to. The ONLY thing that could be wrong is if the motor somehow allows the Neutral side of its internal wiring to connect to the exposed outer chassis of the motor. Since you have your power supply cord's Hot lead connected to he motor's Neutral terminal, an internal connection like that could put the motor case at supply line Hot voltage, a dangerous condition.

How to check for that? As C1 says, if you have a good Ground source, with the motor plugged in and running measure the voltage from Ground to the motor case. If it is zero you probably have little danger. Just to check, measure voltages from Ground to Hot and Neutral wires from the power cord. You should see 100V at Hot, and zero at Neutral IF Japan is using a Grounded Neutral system as we do in North America.

The other check is with a meter for high resistances. Unplug the device from the wall. Measure resistances from power cord Neutral (White) (connected currently to motor grey) to the motor metal case. Measure also resistance from power supply Hot (currently connected to motor white) to motor case. BOTH should be extremely high if there is NO connection from internal motor conductors to outer case metal. That is a "normal" safe design.

Or, just to be safe, you could also reverse the way you have your power supply lines connected.
 

TheNiceGuy

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Dec 23, 2004
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Thanks again guys for your help on this sticky problem. We gotit all working now.
-Jonny
 

TheNiceGuy

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One last quesion while I have your ear:
I also salvaged a nice little water pump off the fan unit. It is a little self contained/sealed submersible impeller type. There are no indicators of any kind on it as to which wire is positive or negative. I can't open it, or it will break the seal. I just guessed and hooked up 2 wires, and it runs great. Is it safe like that?
100v, 60hz, 7w.
 

bryanl

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Oct 15, 2006
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Please say you have the white-white and the grey-black connections each covered with a wire nut of the appropriate size, that is, a plastic twist-on version of the cone-shaped device labelled "HOT" that's covering the red & black wires. Each cut-off wire end should also be covered with either an appropriately sized wire nut or heat-shrink tubing to prevent exposure of the bare copper ends.
 

Paperdoc

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Aug 17, 2006
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On your water pump question, I'm sure what you have done is OK. Any AC motor does not have a + and - terminal. On any small AC motor it will start and run just fine no matter which way the two power supply lines are connected to the motor leads. The only question in your original post was whether the Neutral should be connected to a particular connection in case the motor chassis itself were possibly connected to some other point. I am sure that would NOT be done with a submersible pump/motor, and the connection "polarity" of the motor does not matter - in fact, does not exist.
 
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