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Paranormal Battery box

My next question is whether you have retested the box to see if the original fault is still there, and whether it's consistent. Perhaps there was something in the switch that has now dislodged, or changed as the switch limbered up. Have you tried putting it all back the way it was and seeing if anything is altered by wiggling the switch?

Are the connection terminals of the switch accessible? I keep thinking that if this is a new part, perhaps there's an assembly error, perhaps a crossed wire or a poorly soldered terminal or something.

Final question: where did this box come from? New or used? Is it absolutely certain that it is just a battery box and does not have any other components in it ?
 
bruto said:
My next question is whether you have retested the box to see if the original fault is still there, and whether it's consistent. Perhaps there was something in the switch that has now dislodged, or changed as the switch limbered up. Have you tried putting it all back the way it was and seeing if anything is altered by wiggling the switch?
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Have retested to be the same. Will try wiggling the switch.
But I do notice that the sliding on/off switch is not completely all the way back. But I can only push the switch back that much.
Are the connection terminals of the switch accessible? I keep thinking that if this is a new part, perhaps there's an assembly error, perhaps a crossed wire or a poorly soldered terminal or something. ?
Click to expand...
Not very accessible.
But I'm not about to break up the switch. Even if we do break it up, we might not be able to find out what happened. [joking]After this many posts I'm beginning to think this battery box is my "golden-goose" for the JREF million. Who wants to join me to get the million? :) [/joking]

Final question: where did this box come from? New or used? Is it absolutely certain that it is just a battery box and does not have any other components in it ?
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New, bought from a shop.
Looks remarkbly similar to this.
Battery%20holder%204%20AA%20cover.jpg

http://www.xleris.com/battery-holder-with-switch-cover-p-43.html
With the exception that the top "row" of plastic covering the switch and wire is not there. So I can see the wires and the switch. The switch is at the top left corner.
 
Perhaps it is an assembly error.

But what kind of science would have caused such a battery box to have a voltage even when there is no battery?
 
Jyera said:
I understand it is equivalent.
But a open circuit (infinity resistance) will not draw any current. When I switch off the battery box, there is no leakage of battery. I
Click to expand...

?? You said there was "leakage". You measured 1.49v when the switch was off. There is no magic here. There is a connection through the box or you wouldn't measure it, but it doesn't seem to be the switch.

I understand what you mean. However I have not touched any conducting part of the circuit while doing the measurement. so I cannot say my body contributed to the voltage. Placing my digital multimeter under my fluoresent light yields no readings. It simple puzzles me why a simple on-off switch without battery can provide a voltage.
Click to expand...

I was being a little humorous with my examples. You can measure milli volts in many places. Could be leakage from your house wiring if it's not all well grounded for example. Could be static if you're in a cold dry area. It could also be more mundane, in your instrument, meaning that your meter is not very accurate at that level.



Measured those paths, no short.
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Yes there is and, yes you measured it, at 1.49v, remember?;)

Keep at it some more:)
 
Digital voltmeters generally have high impedance, like 10 Mohms. If the resistance of the switch when "open" is 20 Mohms, one third of the battery voltage will be across the meter, so that's what it will read.
 
Jyera said:
Battery%20holder%204%20AA%20cover.jpg

http://www.xleris.com/battery-holder-with-switch-cover-p-43.html
With the exception that the top "row" of plastic covering the switch and wire is not there. So I can see the wires and the switch. The switch is at the top left corner.
Click to expand...

The red wire will go to the battery point on the top right corner, where the 1 is. The black will go across towards the top left corner, into one side of the switch (connection A). The other side of the switch will have a small wire connected to the top left battery terminal (connection B) (or be directly connected).

My guess is that you have a stray strand of wire or that shiny pin holding it together has damaged a wire.

First put in the batteries and make sure you still have the mystery voltage between red and black with the switch OFF, and then;

With the switch OFF, Check the resistance, without batteries, between terminal 1 and the three terminal points to the left of it. They should all be open circuit. If they are, check the same between the BLACK wire and each terminal point. They should also all be open circuit, but maybe not between BLACK and the terminal to the left of 1, which is my best guess.

Lastly, break the sucker open and look at the connections and wires closely.:boggled:
 
69dodge said:
Digital voltmeters generally have high impedance, like 10 Mohms. If the resistance of the switch when "open" is 20 Mohms, one third of the battery voltage will be across the meter, so that's what it will read.
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In the instrument, yes, but I think he said he was able to measure down to 2 Mohms which is another order of size, and he did not see that.
 
Elind said:
?? You said there was "leakage". You measured 1.49v when the switch was off. There is no magic here. There is a connection through the box or you wouldn't measure it, but it doesn't seem to be the switch.
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Sorry. My fault. What I meant was that if the switch is a real open circuit(infinity resistance). It will not draw any current. And I would not be able to measure any voltage.

I was being a little humorous with my examples. You can measure milli volts in many places. Could be leakage from your house wiring if it's not all well grounded for example. Could be static if you're in a cold dry area. It could also be more mundane, in your instrument, meaning that your meter is not very accurate at that level.
Click to expand...
Yes I know your are just being humorous. trust I do not wear sweaty socks.
Yes there is and, yes you measured it, at 1.49v, remember?;)
Keep at it some more:)
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Err.... I thought a short is like short-circuit with the shorting connector at 0_ohm. So if it is a short across the switch, the reading should always maintain at 4.4V with the 4x1.1V batteries.
 
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69dodge said:
Digital voltmeters generally have high impedance, like 10 Mohms. If the resistance of the switch when "open" is 20 Mohms, one third of the battery voltage will be across the meter, so that's what it will read.
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My digital multimeter can only measure a Max of 2Mohm.
Is there any simple thing I can do to actually do to make it measure 20 Mohm?
 
Jyera said:
My digital multimeter can only measure a Max of 2Mohm.
Is there any simple thing I can do to actually do to make it measure 20 Mohm?
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Basically, what you already did. If you measure the voltage with the switch off, and the meter reads 1/3 of the true battery voltage, that means that the resistance of the switch, when it's off, is twice the resistance of the meter.

But this is not a problem, practically speaking. If you attach some electrical device to the battery holder and slide the switch off, the device will turn off. (Unless it can run on microamps of current.)
 
69dodge said:
Basically, what you already did. If you measure the voltage with the switch off, and the meter reads 1/3 of the true battery voltage, that means that the resistance of the switch, when it's off, is twice the resistance of the meter.

But this is not a problem, practically speaking. If you attach some electrical device to the battery holder and slide the switch off, the device will turn off. (Unless it can run on microamps of current.)
Click to expand...

I concur - I suppose another way would be to measure the voltage drop when a known load is applied. This allows you to measure the internal resistance of the battery+wires+switch combination. Subtract the internal resistance of the batteries (same measurement, but the batteries need to be used outside the box) to get the resistance of the box configuration.

And, btw, this is very common - especially with slide switches. In fact, this is a good example of the difference between real and ideal components.
 
Soapy Sam said:
I nominate this thread for the...the...the jolly interesting thread award.
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Glad you enjoyed it so far.
Must give thanks to all for helping out to troubleshoot.

[joking]Only sad thing is that my "golden goose" is fading away day-by-day :( . I thought it would really be a jref challenge winner.[/joking]

But wait... some more to explain...
 
I measured the voltage of the switch in the open/off position, without the batteries in the battery box. And to my surprise !!! It shows a voltage, 2 mV.
And the voltage did not go to zero.

No battery and yet there is a voltage ??!!?
Click to expand...

How to explain this?
 
Jyera said:
How to explain this?
Click to expand...

Step one: replace battery in digital voltmeter and try again, because a low battery can cause this sort of error.

Step two: Crack open that battery box and check every little thing in it. It can't be that complicated. At least, on the off chance that some slightly magical combination of things has caused it to behave as if it had a capacitor in it, try briefly shorting the terminals together after removing the batteries, and try again.

Step three: call an exorcist.
 
Jyera said:
Err.... I thought a short is like short-circuit with the shorting connector at 0_ohm. So if it is a short across the switch, the reading should always maintain at 4.4V with the 4x1.1V batteries.
Click to expand...
No, as "69" (love that handle) has already explained, a very high resistance will still measure a voltage even though it will not allow a usable current (V=RA), although it is still possible that there is another short somewhere else between the batteries, as I suggested checking for.

One other simple way that occurs to check that is to put a small 1.5v flashlight bulb across the terminals when the switch is OFF. Your 1.49v should light it up, unless it is a very high resistance short, like 20 mohms in the switch.

BTW, by now your batteries must be dead. Shall we start again with new batteries and boost it up to 6v?:D
 
Hi all heres the latest attempt.

Multimeter battery
Changed the battery to the digital multimeter. The old battery measured 9.1V and the new battery measured 9.3V. I left the new battery in the meter and used it for the following measurements.

Measurement with set A batteries These are the "original" batteries used above.
Individual Measurement of Voltage and Resistance all 4 AA batteries.
1.136V, 1.138V, 1.135V, 1,140V,
-0.778Ohm, -0.778Ohm, -0.777Ohm, -0.778Ohm.

When the batteries are placed in the battery box, and
voltage across the output is mesaured.
Switch @ "on" : 4.54V
Switch @ off : 2.26V (this is inconsistent also measured 1.82V, 2.4V)

Measurement with set B batteries
Individual Measurement of Voltage and Resistance all 4 AA batteries.
1.044V, 1.041V, 1.042V, 1,042V,
-0.771Ohm, -0.771Ohm, -0.771Ohm, -0.771Ohm.

When the batteries are placed in the battery box, and
voltage across the output is mesaured.
Switch @ "on" : 4.16V
Switch @ off : 2.23V

Resistance were measured by setting the Digital Multimeter to 2M Ohm range, and placed the black/red at the positive/negative terminal of the battery respectively.
 
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