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Repair Sylvania Model 72032 LED Lite?
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KenO
Nov 2, 2012, 12:28:28 PM11/2/12
to
Have a Sylvania Model 72032 LED Lite that stopped working.
Did some checking and seems the batteries go bad. http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/product-reviews/B000KJZNBW
Would like to replace it with a better battery if possible.
Appreciate any tips concerning repair of either the Sylvania Model 72032 LED Lite or LED lites in general.
Thanks
Ken
Did some checking and seems the batteries go bad. http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/product-reviews/B000KJZNBW
Would like to replace it with a better battery if possible.
Appreciate any tips concerning repair of either the Sylvania Model 72032 LED Lite or LED lites in general.
Thanks
Ken
hr(bob) hofmann@att.net
Nov 2, 2012, 4:54:34 PM11/2/12
to
On Nov 2, 11:28 am, KenO <kenithol...@yahoo.com> wrote:
> Have a Sylvania Model 72032 LED Lite that stopped working.
>
> Did some checking and seems the batteries go bad.http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/product-r...
> Have a Sylvania Model 72032 LED Lite that stopped working.
>
>
> Would like to replace it with a better battery if possible.
>
> Appreciate any tips concerning repair of either the Sylvania Model 72032 LED Lite or LED lites in general.
>
> Thanks
>
> Ken
I am not familiar with that lite, but have you taken it apart to see
> Would like to replace it with a better battery if possible.
>
> Appreciate any tips concerning repair of either the Sylvania Model 72032 LED Lite or LED lites in general.
>
> Thanks
>
> Ken
what kind of batteries it uses? That is the first step.
Franc Zabkar
Nov 3, 2012, 5:00:10 AM11/3/12
to
On Fri, 2 Nov 2012 09:28:28 -0700 (PDT), KenO <kenit...@yahoo.com>
put finger to keyboard and composed:
>Have a Sylvania Model 72032 LED Lite that stopped working.
>
>Did some checking and seems the batteries go bad. http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/product-reviews/B000KJZNBW
>
>Would like to replace it with a better battery if possible.
I'm wondering if supercaps or ultracapacitors could be used in this
application.
- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
put finger to keyboard and composed:
>Have a Sylvania Model 72032 LED Lite that stopped working.
>
>Did some checking and seems the batteries go bad. http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/product-reviews/B000KJZNBW
>
>Would like to replace it with a better battery if possible.
application.
- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
whit3rd
Nov 3, 2012, 2:33:10 PM11/3/12
to
On Friday, November 2, 2012 9:28:28 AM UTC-7, KenO wrote:
> Have a Sylvania Model 72032 LED Lite that stopped working.
...
> Have a Sylvania Model 72032 LED Lite that stopped working.
> Did some checking and seems the batteries go bad
If the battery is bad, replace it. The typical
'emergency lighting' appliance has to be tested
from time to time, and commercial units recommend
battery replacement every ten years, regardless of test.
So, figure a battery has 10 year mean time between failure.
There might be 10% of the batteries that fail in the first year,
and another 10% that are good after fifteen years.
Collecting anecdotes over the internet isn't going to be
very useful in this kind of situation. Maintaining your
emergency lighting, IS very useful. So, do it.
KenO
Nov 6, 2012, 12:50:55 PM11/6/12
to
"I am not familiar with that lite, but have you taken it apart to see what kind of batteries it uses? That is the first step."
Bob I Agree.
Also would like to take it apart without totally destroying it.
Do you have any suggestions, especially concerning de-bonding the plastic parts.
There is a plastic ring around the main LEDs end and a clear plastic cover around the night lite LED end. Amazon has a good photo.
http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/dp/B000KJZNBW
Was thinking of using a wrench to try to twist off but am afraid of shattering these parts.
Am wondering about de-bonders?
Ken
hr(bob) hofmann@att.net
Nov 6, 2012, 10:13:58 PM11/6/12
to
On Nov 6, 11:50 am, KenO <kenithol...@yahoo.com> wrote:
> "I am not familiar with that lite, but have you taken it apart to see what kind of batteries it uses? That is the first step."
>
> Bob I Agree.
>
> Also would like to take it apart without totally destroying it.
>
> Do you have any suggestions, especially concerning de-bonding the plastic parts.
>
> There is a plastic ring around the main LEDs end and a clear plastic cover around the night lite LED end. Amazon has a good photo.http://www.amazon.com/Sylvania-72032-Sensor-Failure-FAILURE/dp/B000KJ...
> "I am not familiar with that lite, but have you taken it apart to see what kind of batteries it uses? That is the first step."
>
> Bob I Agree.
>
> Also would like to take it apart without totally destroying it.
>
> Do you have any suggestions, especially concerning de-bonding the plastic parts.
>
>
> Was thinking of using a wrench to try to twist off but am afraid of shattering these parts.
>
> Am wondering about de-bonders?
>
> Ken
It's not that expensive at $14. I would take a very sharp/brand-new
> Was thinking of using a wrench to try to twist off but am afraid of shattering these parts.
>
> Am wondering about de-bonders?
>
> Ken
utility knife to the seams and carefully cut the unit at all the
visible seams, like in a circle around where the clear lens fastens to
the body, and elsewhere that you can find anything that looks like
where two pieces of plastic were joined together. Superglue is great
at re-attaching these separate pieces after you have fixed it.
KenO
Nov 10, 2012, 3:57:32 PM11/10/12
to
Finally got the non working Sylvania Model 72032 LED Lite apart and checked the battery and fuse and they were OK but a component next to the fuse showed burn marks so am guessing this was what gave out.
While it is sold in USA as the Sylvania Model 72032 LED Lite, it is actually manufactured by LOMAK and inside the plastic shell is marked T4-1.
Did some searching using both Sylvania Model 72032 and LOMAK Model 72032 but to date have been unable to find either a parts list or schematic for it.
Would be interested in any suggestions how to find either the parts list or schematic.
Alternatively would be interested in trying to determine what the burnt component is.
I have taken some photos and would be glad to post if there is interest.
Thanks again for all your help.
Ken
While it is sold in USA as the Sylvania Model 72032 LED Lite, it is actually manufactured by LOMAK and inside the plastic shell is marked T4-1.
Did some searching using both Sylvania Model 72032 and LOMAK Model 72032 but to date have been unable to find either a parts list or schematic for it.
Would be interested in any suggestions how to find either the parts list or schematic.
Alternatively would be interested in trying to determine what the burnt component is.
I have taken some photos and would be glad to post if there is interest.
Thanks again for all your help.
Ken
Franc Zabkar
Nov 11, 2012, 3:27:45 PM11/11/12
to
On Sat, 10 Nov 2012 12:57:32 -0800 (PST), KenO <kenit...@yahoo.com>
put finger to keyboard and composed:
>I have taken some photos and would be glad to post if there is interest.
I'm interested.
KenO
Nov 13, 2012, 10:51:10 AM11/13/12
to
"I'm interested...Franc Zabkar...Please remove one 'i' from my address when replying by email."
Franc,
I did not see a way to post the Sylvania Model 72032 LED Lite Photos on the forum so tried sending them to you but got error message The message To: Cc: or Bcc: field contains a malformed email address.
If there is a way to post photos on forum please tell me how.
Thanks again for all your help!
Ken
Franc,
I did not see a way to post the Sylvania Model 72032 LED Lite Photos on the forum so tried sending them to you but got error message The message To: Cc: or Bcc: field contains a malformed email address.
If there is a way to post photos on forum please tell me how.
Thanks again for all your help!
Ken
Franc Zabkar
Nov 13, 2012, 4:02:24 PM11/13/12
to
On Tue, 13 Nov 2012 07:51:10 -0800 (PST), KenO <kenit...@yahoo.com>
sharing service.
As for my email address, it is valid, but you need to remove one "i"
...
- Franc Zabkar
--
put finger to keyboard and composed:
>I did not see a way to post the Sylvania Model 72032 LED Lite Photos on the forum so tried sending them to you but got error message The message To: Cc: or Bcc: field contains a malformed email address.
>
>If there is a way to post photos on forum please tell me how.
This is a text-only forum. You could upload your photos to a file
>
>If there is a way to post photos on forum please tell me how.
sharing service.
As for my email address, it is valid, but you need to remove one "i"
...
- Franc Zabkar
--
KenO
Nov 16, 2012, 1:08:14 PM11/16/12
to fza...@iinternode.on.net
If you are the only person interested in the photos, it would be easiest to send them to you.
"As for my email address, it is valid, but you need to remove one "i" Franc Zabkar
Somehow I am having problems with your email address even after removing an "i".
Please send me a "test email" and will reply with photos.
Thank you again for your help!
Ken
"As for my email address, it is valid, but you need to remove one "i" Franc Zabkar
Somehow I am having problems with your email address even after removing an "i".
Please send me a "test email" and will reply with photos.
Thank you again for your help!
Ken
Franc Zabkar
Nov 19, 2012, 3:50:05 PM11/19/12
to
On Fri, 16 Nov 2012 10:08:14 -0800 (PST), KenO <kenit...@yahoo.com>
http://www.users.on.net/~fzabkar/Sylvania_LED_light/
put finger to keyboard and composed:
>If you are the only person interested in the photos, it would be easiest to send them to you.
I have taken the liberty of uploading your photos to my web space:
http://www.users.on.net/~fzabkar/Sylvania_LED_light/
Franc Zabkar
Nov 19, 2012, 4:08:13 PM11/19/12
to
On Tue, 20 Nov 2012 07:50:05 +1100, Franc Zabkar
<fza...@iinternode.on.net> put finger to keyboard and composed:
>On Fri, 16 Nov 2012 10:08:14 -0800 (PST), KenO <kenit...@yahoo.com>
>put finger to keyboard and composed:
>
>>If you are the only person interested in the photos, it would be easiest to send them to you.
>
>I have taken the liberty of uploading your photos to my web space:
>http://www.users.on.net/~fzabkar/Sylvania_LED_light/
The component below the fuse looks like it may be a series resistor
for the zener diode (ZD1). Together they would constitute a crude
zener regulated DC supply.
Measure the voltage across the zener and compare it against the
markings on the zener's body. This should tell you if the supply is
working correctly. I expect that there would be a filter capacitor on
the reverse side of the PCB (could we see that as well?).
<fza...@iinternode.on.net> put finger to keyboard and composed:
>On Fri, 16 Nov 2012 10:08:14 -0800 (PST), KenO <kenit...@yahoo.com>
>put finger to keyboard and composed:
>
>>If you are the only person interested in the photos, it would be easiest to send them to you.
>
>I have taken the liberty of uploading your photos to my web space:
>http://www.users.on.net/~fzabkar/Sylvania_LED_light/
for the zener diode (ZD1). Together they would constitute a crude
zener regulated DC supply.
Measure the voltage across the zener and compare it against the
markings on the zener's body. This should tell you if the supply is
working correctly. I expect that there would be a filter capacitor on
the reverse side of the PCB (could we see that as well?).
Franc Zabkar
Nov 20, 2012, 2:26:27 PM11/20/12
to
On Tue, 20 Nov 2012 07:50:05 +1100, Franc Zabkar
<fza...@iinternode.on.net> put finger to keyboard and composed:
>On Fri, 16 Nov 2012 10:08:14 -0800 (PST), KenO <kenit...@yahoo.com>
>put finger to keyboard and composed:
>
>>If you are the only person interested in the photos, it would be easiest to send them to you.
>
>I have taken the liberty of uploading your photos to my web space:
>http://www.users.on.net/~fzabkar/Sylvania_LED_light/
KenO
Nov 23, 2012, 1:02:08 PM11/23/12
to
Franc,
Thanks for all your help!!!
"Measure the voltage across the zener and compare it against the markings on the zener's body. This should tell you if the supply is working correctly."
Am a electronics beginner which is the reason I am interested in trouble shooting this LED Lite.
How do I "Measure the voltage across the zener"?
Ken
Thanks for all your help!!!
"Measure the voltage across the zener and compare it against the markings on the zener's body. This should tell you if the supply is working correctly."
How do I "Measure the voltage across the zener"?
Ken
Franc Zabkar
Nov 23, 2012, 2:33:13 PM11/23/12
to
On Fri, 23 Nov 2012 10:02:08 -0800 (PST), KenO <kenit...@yahoo.com>
ask this question, then you shouldn't be working on this device. There
are lethal AC voltages inside.
That said, here is the zener regulated supply:
Vin o-- R --|----|---o Vout
| |
Z C
| |
0V o-------|----|---o
Z = zener diode
C = electrolytic capacitor on reverse side
R = series resistor
Measure Vin with respect to 0V, and also measure the voltage between
Vout and 0V.
Examine the markings on the zener.
put finger to keyboard and composed:
>"Measure the voltage across the zener and compare it against the markings on the zener's body. This should tell you if the supply is working correctly."
>
>Am a electronics beginner which is the reason I am interested in trouble shooting this LED Lite.
>
>How do I "Measure the voltage across the zener"?
With respect, voltage measurement is a very basic task. If you have to
>
>Am a electronics beginner which is the reason I am interested in trouble shooting this LED Lite.
>
>How do I "Measure the voltage across the zener"?
ask this question, then you shouldn't be working on this device. There
are lethal AC voltages inside.
That said, here is the zener regulated supply:
Vin o-- R --|----|---o Vout
| |
Z C
| |
0V o-------|----|---o
Z = zener diode
C = electrolytic capacitor on reverse side
R = series resistor
Measure Vin with respect to 0V, and also measure the voltage between
Vout and 0V.
Examine the markings on the zener.
Franc Zabkar
Nov 23, 2012, 2:44:10 PM11/23/12
to
On Sat, 24 Nov 2012 06:33:13 +1100, Franc Zabkar
<fza...@iinternode.on.net> put finger to keyboard and composed:
>That said, here is the zener regulated supply:
>
>Vin o-- R --|----|---o Vout
> | |
> Z C
> | |
>0V o-------|----|---o
>
>Z = zener diode
>C = electrolytic capacitor on reverse side
>R = series resistor
>
>Measure Vin with respect to 0V, and also measure the voltage between
>Vout and 0V.
>
>Examine the markings on the zener.
Here are you measurement locations:
http://www.users.on.net/~fzabkar/Sylvania_LED_light/FS-2ed2863_reg.jpg
<fza...@iinternode.on.net> put finger to keyboard and composed:
>That said, here is the zener regulated supply:
>
>Vin o-- R --|----|---o Vout
> | |
> Z C
> | |
>0V o-------|----|---o
>
>Z = zener diode
>C = electrolytic capacitor on reverse side
>R = series resistor
>
>Measure Vin with respect to 0V, and also measure the voltage between
>Vout and 0V.
>
>Examine the markings on the zener.
http://www.users.on.net/~fzabkar/Sylvania_LED_light/FS-2ed2863_reg.jpg
KenO
Nov 24, 2012, 1:53:17 PM11/24/12
to fza...@iinternode.on.net
Franc,
"With respect, voltage measurement is a very basic task. If you have to
ask this question, then you shouldn't be working on this device. There
are lethal AC voltages inside."
Agree, which is why I have not plugged in this LED Lite to AC.
Had hoped I could do the measurements without plugging it in!
"Examine the markings on the zener." What am I looking for? From your looking at the photos I sent what are the possible variations?
Thanks again for your detailed explanations and help!
Ken
"With respect, voltage measurement is a very basic task. If you have to
ask this question, then you shouldn't be working on this device. There
are lethal AC voltages inside."
Had hoped I could do the measurements without plugging it in!
"Examine the markings on the zener." What am I looking for? From your looking at the photos I sent what are the possible variations?
Thanks again for your detailed explanations and help!
Ken
KenO
Nov 24, 2012, 2:04:14 PM11/24/12
to fza...@iinternode.on.net
Franc,
"Examine the markings on the zener."
Forgot to ask, do you recommend trying to clean the zener diode to better see any band markings?
If yes, what do you suggest?
Thanks
Ken
"Examine the markings on the zener."
If yes, what do you suggest?
Thanks
Ken
KenO
Nov 24, 2012, 3:42:17 PM11/24/12
to fza...@iinternode.on.net
Franc,
Was going to ask you about testing the zener diode but what I found said you need an analog meter which I do not have.
http://www.electronicrepairguide.com/testing-zener-diode.html
I did find an article on How to Read Zener Diode Code
http://ezinearticles.com/?How-to-Read-Zener-Diode-Code&id=40081
Also found a basic zener diode test and wonder how accurate it is.
http://www.learningaboutelectronics.com/Articles/How-to-test-a-zener-diode
"If you want to check a zener diode is whether it is good or defective, there are two simple but effective quick tests that you can do.
We will discuss both tests in this article.
Test a Zener Diode with an Ohmmeter of a Multimeter
A very good test you can do is to check a zener diode with your multimeter set to the ohmmeter setting.
This is a simple test we can do to check whether it is good, open, or shorted.
So we take the ohmmeter and place it across the leads of the diode. The orientation is very important.
Anode-Cathode Diode Resistance Test
We first take the ohmmeter and place the positive probe on the anode of the diode (the black part of the diode_ and the negative probe on the cathode of the diode (the black strip), as shown above. In this setup, the diode should read a moderately low resistance, maybe a few hundred thousands of ohms. For example, you may read around 450KΩ.
Zener Diode Anode to Cathode Resistance Test
Cathode-Anode Diode Resistance Test
Now take the ohmmeter and switch the probes around so that the positive probe of the multimeter is now on the cathode of the diode and the negative lead on the anode. In this setup now, the diode should read a much higher resistance, well over 1MΩ. A typical reading may, for example, be 2.3MΩ. The multimeter may even indicate 'OL' for an open circuit, since the resistance is so high.
Zener Diode Cathode to Anode Resistance Test
If you read a moderately low resistance with the leads on the zener diode one way and a high resistance with the leads the other, this is a sign that the zener diode is good. A zener diode should read relatively low resistance in the forward biased direction and very high resistance in the reverse biased direction.
Open Diode
If a zener diode reads high resistance in both directions, this is a sign that the diode is open. A diode should not measure very high resistance in the forward biased direction. The diode should be replaced in the circuit.
Shorted Diode
If the zener diode reads low resistances in both directions, this is a sign that the diode is shorted. A diode should not measure low resistance in the reverse biased direction. The diode should be replaced in the circuit.
How to Test a Zener Diode with a Voltmeter of a Multimeter
A second test you can do to check to see whether a zener diode is defective or not is to measure its voltage with a voltmeter of a multimeter (or simply just a voltmeter if you have one.)
In order for this test to work, we must feed voltage to the zener diode in reverse bias in series with a resistor. The voltage must be higher than the rated zener voltage of the zener diode. In the circuit below, we feed the zener diode and a 1KΩ resistor 9 volts from a 9-volt battery. The zener diode is rated for 5.1V, well below the 9 volts, so the test will work wtih this diode. When measuring the voltage across the zener diode, it must measure a voltage near its rated zener voltage.
Zener Diode Voltage Test
If a zener diode reads a voltage near its rated zener voltage, VZ, then it is good.
Open Diode
If the diode reads a much higher voltage, of or near the voltage of the supply voltage feeding it, it is open and, thus, defective. It should be replaced.
Shorted Diode
If the diode is reading a much lower voltage than its rated voltage, such as near 0V, it is shorted internally and, thus, is defective and must be replaced."
What do you think?
Ken
Was going to ask you about testing the zener diode but what I found said you need an analog meter which I do not have.
http://www.electronicrepairguide.com/testing-zener-diode.html
I did find an article on How to Read Zener Diode Code
http://ezinearticles.com/?How-to-Read-Zener-Diode-Code&id=40081
Also found a basic zener diode test and wonder how accurate it is.
http://www.learningaboutelectronics.com/Articles/How-to-test-a-zener-diode
"If you want to check a zener diode is whether it is good or defective, there are two simple but effective quick tests that you can do.
We will discuss both tests in this article.
Test a Zener Diode with an Ohmmeter of a Multimeter
A very good test you can do is to check a zener diode with your multimeter set to the ohmmeter setting.
This is a simple test we can do to check whether it is good, open, or shorted.
So we take the ohmmeter and place it across the leads of the diode. The orientation is very important.
Anode-Cathode Diode Resistance Test
We first take the ohmmeter and place the positive probe on the anode of the diode (the black part of the diode_ and the negative probe on the cathode of the diode (the black strip), as shown above. In this setup, the diode should read a moderately low resistance, maybe a few hundred thousands of ohms. For example, you may read around 450KΩ.
Zener Diode Anode to Cathode Resistance Test
Cathode-Anode Diode Resistance Test
Now take the ohmmeter and switch the probes around so that the positive probe of the multimeter is now on the cathode of the diode and the negative lead on the anode. In this setup now, the diode should read a much higher resistance, well over 1MΩ. A typical reading may, for example, be 2.3MΩ. The multimeter may even indicate 'OL' for an open circuit, since the resistance is so high.
Zener Diode Cathode to Anode Resistance Test
If you read a moderately low resistance with the leads on the zener diode one way and a high resistance with the leads the other, this is a sign that the zener diode is good. A zener diode should read relatively low resistance in the forward biased direction and very high resistance in the reverse biased direction.
Open Diode
If a zener diode reads high resistance in both directions, this is a sign that the diode is open. A diode should not measure very high resistance in the forward biased direction. The diode should be replaced in the circuit.
Shorted Diode
If the zener diode reads low resistances in both directions, this is a sign that the diode is shorted. A diode should not measure low resistance in the reverse biased direction. The diode should be replaced in the circuit.
How to Test a Zener Diode with a Voltmeter of a Multimeter
A second test you can do to check to see whether a zener diode is defective or not is to measure its voltage with a voltmeter of a multimeter (or simply just a voltmeter if you have one.)
In order for this test to work, we must feed voltage to the zener diode in reverse bias in series with a resistor. The voltage must be higher than the rated zener voltage of the zener diode. In the circuit below, we feed the zener diode and a 1KΩ resistor 9 volts from a 9-volt battery. The zener diode is rated for 5.1V, well below the 9 volts, so the test will work wtih this diode. When measuring the voltage across the zener diode, it must measure a voltage near its rated zener voltage.
Zener Diode Voltage Test
If a zener diode reads a voltage near its rated zener voltage, VZ, then it is good.
Open Diode
If the diode reads a much higher voltage, of or near the voltage of the supply voltage feeding it, it is open and, thus, defective. It should be replaced.
Shorted Diode
If the diode is reading a much lower voltage than its rated voltage, such as near 0V, it is shorted internally and, thus, is defective and must be replaced."
What do you think?
Ken
tuinkabouter
Nov 24, 2012, 5:34:01 PM11/24/12
to
On 11/24/2012 9:42 PM, KenO wrote:
> Franc,
>
> A second test you can do to check to see whether a zener diode is defective or not is to measure its voltage with a voltmeter of a multimeter (or simply just a voltmeter if you have one.)
>
> In order for this test to work, we must feed voltage to the zener diode in reverse bias in series with a resistor. The voltage must be higher than the rated zener voltage of the zener diode. In the circuit below, we feed the zener diode and a 1KΩ resistor 9 volts from a 9-volt battery. The zener diode is rated for 5.1V, well below the 9 volts, so the test will work wtih this diode. When measuring the voltage across the zener diode, it must measure a voltage near its rated zener voltage.
>
> Zener Diode Voltage Test
>
> If a zener diode reads a voltage near its rated zener voltage, VZ, then it is good.
> Open Diode
>
> If the diode reads a much higher voltage, of or near the voltage of the supply voltage feeding it, it is open and, thus, defective. It should be replaced.
> Shorted Diode
>
> If the diode is reading a much lower voltage than its rated voltage, such as near 0V, it is shorted internally and, thus, is defective and must be replaced."
>
> What do you think?
Explane the readings when you connect the zener in reverse.
Wat are the readings when you use 9v AC instead of DC.
> Franc,
>
> A second test you can do to check to see whether a zener diode is defective or not is to measure its voltage with a voltmeter of a multimeter (or simply just a voltmeter if you have one.)
>
> In order for this test to work, we must feed voltage to the zener diode in reverse bias in series with a resistor. The voltage must be higher than the rated zener voltage of the zener diode. In the circuit below, we feed the zener diode and a 1KΩ resistor 9 volts from a 9-volt battery. The zener diode is rated for 5.1V, well below the 9 volts, so the test will work wtih this diode. When measuring the voltage across the zener diode, it must measure a voltage near its rated zener voltage.
>
> Zener Diode Voltage Test
>
> If a zener diode reads a voltage near its rated zener voltage, VZ, then it is good.
> Open Diode
>
> If the diode reads a much higher voltage, of or near the voltage of the supply voltage feeding it, it is open and, thus, defective. It should be replaced.
> Shorted Diode
>
> If the diode is reading a much lower voltage than its rated voltage, such as near 0V, it is shorted internally and, thus, is defective and must be replaced."
>
> What do you think?
Wat are the readings when you use 9v AC instead of DC.
amdx
Nov 24, 2012, 6:46:24 PM11/24/12
to
please post it. I need three!
Mikek
Franc Zabkar
Nov 26, 2012, 6:41:57 PM11/26/12
to
On Sat, 24 Nov 2012 12:42:17 -0800 (PST), KenO <kenit...@yahoo.com>
Note that when performing resistance measurements, you need to do so
in the absence of power.
To answer your other questions, I use isopropyl alcohol to clean PCBs
but I'd be wary of using it on device markings. Sometimes they rub
off.
The markings on the zener usually reflect its breakdown voltage.
The battery appears to have three cells. Is it a 3.6V type? Does it
have a mAH rating on the body?
I notice that there appears to be extensive galvanic corrosion at the
switch terminals. I expect that the associated copper traces may
eventually turn black.
put finger to keyboard and composed:
>A very good test you can do is to check a zener diode with your multimeter set to the ohmmeter setting.
>
>This is a simple test we can do to check whether it is good, open, or shorted.
What readings did you find? Did you also measure the resistance of R?
>
>This is a simple test we can do to check whether it is good, open, or shorted.
Note that when performing resistance measurements, you need to do so
in the absence of power.
To answer your other questions, I use isopropyl alcohol to clean PCBs
but I'd be wary of using it on device markings. Sometimes they rub
off.
The markings on the zener usually reflect its breakdown voltage.
The battery appears to have three cells. Is it a 3.6V type? Does it
have a mAH rating on the body?
I notice that there appears to be extensive galvanic corrosion at the
switch terminals. I expect that the associated copper traces may
eventually turn black.
KenO
Nov 27, 2012, 10:29:51 AM11/27/12
to fza...@iinternode.on.net
Franc,
These are the results
Zener markings I could see N1 & A
power off R series resistor ~22M Ohms
Zener Test with Ohmmeter of Multimeter
Negative Probe on Cathode (Black Strip) ~140 K Ohms
Positive Probe on Cathode (Black Strip) ~167 K Ohms
power on
Vin ~111 V
Vout to 0 V ~200 mV
"If the diode is reading a much lower voltage than its rated voltage, such as near 0V"
From tests seems Zener is Shorted.
Since the zener was destroyed from a "power surge" what upgrade do you suggest to prevent this from happening?
Ken
These are the results
Zener markings I could see N1 & A
power off R series resistor ~22M Ohms
Zener Test with Ohmmeter of Multimeter
Negative Probe on Cathode (Black Strip) ~140 K Ohms
Positive Probe on Cathode (Black Strip) ~167 K Ohms
power on
Vin ~111 V
Vout to 0 V ~200 mV
"If the diode is reading a much lower voltage than its rated voltage, such as near 0V"
Since the zener was destroyed from a "power surge" what upgrade do you suggest to prevent this from happening?
Ken
KenO
Nov 27, 2012, 11:09:08 AM11/27/12
to fza...@iinternode.on.net
"The battery appears to have three cells. Is it a 3.6V type? Does it have a mAH rating on the body?"
Was finally able to locate this LED Lite on the OEMs website.
http://www.lomak.com/product_lv3.php?id=255
It is listed as Model 33030008A
Bat info Ni-MH 3.6V 110 AH
Ken
KenO
Nov 27, 2012, 11:17:53 AM11/27/12
to
Mikek & Everyone,
"I have the same light, if you find a good battery for replacement, please post it. I need three!"
I would like to convert them to rechargeable Li if possible.
Did a quick search and found http://www.gpbatteries.com/index.php?option=com_k2&view=item&layout=item&id=291&Itemid=120 which lists rechargeable Lithium Cylindrical, Lithium Prismatic, and Lithium Polymer.
Any suggestions concerning what is the best for LED lites and what is needed to convert this Ni-MH Lite to Li?
Thanks
Ken
"I have the same light, if you find a good battery for replacement, please post it. I need three!"
Did a quick search and found http://www.gpbatteries.com/index.php?option=com_k2&view=item&layout=item&id=291&Itemid=120 which lists rechargeable Lithium Cylindrical, Lithium Prismatic, and Lithium Polymer.
Any suggestions concerning what is the best for LED lites and what is needed to convert this Ni-MH Lite to Li?
Thanks
Ken
Franc Zabkar
Nov 29, 2012, 5:51:12 AM11/29/12
to
On Tue, 27 Nov 2012 07:29:51 -0800 (PST), KenO <kenit...@yahoo.com>
>power off R series resistor ~22M Ohms
It looks like this is open circuit.
>Zener Test with Ohmmeter of Multimeter
>
>Negative Probe on Cathode (Black Strip) ~140 K Ohms
>
>Positive Probe on Cathode (Black Strip) ~167 K Ohms
I'm not sure what you are doing here. You should connect one probe to
one end of the zener, and the other probe to the other end. If that's
what you were doing, then you should have used the diode test function
of your meter.
>power on
>
>Vin ~111 V
>
>Vout to 0 V ~200 mV
This is consistent with an open circuited series resistor. The zener
is not shorted, as per your previous measurement.
That said, I'm surprised that Vin is so high. I can't imagine that the
zener voltage would be more than 10V, so this would mean that the
series resistor would need to drop a lot of voltage. It seems too
small for that kind of wattage. Something doesn't look right to me,
but I can't see the circuit clearly enough (too many components
obscuring the PCB). I don't think I can help you without a circuit
diagram.
put finger to keyboard and composed:
>Zener markings I could see N1 & A
Sorry, I can't make anything out of that.
>power off R series resistor ~22M Ohms
>Zener Test with Ohmmeter of Multimeter
>
>Negative Probe on Cathode (Black Strip) ~140 K Ohms
>
>Positive Probe on Cathode (Black Strip) ~167 K Ohms
one end of the zener, and the other probe to the other end. If that's
what you were doing, then you should have used the diode test function
of your meter.
>power on
>
>Vin ~111 V
>
>Vout to 0 V ~200 mV
is not shorted, as per your previous measurement.
That said, I'm surprised that Vin is so high. I can't imagine that the
zener voltage would be more than 10V, so this would mean that the
series resistor would need to drop a lot of voltage. It seems too
small for that kind of wattage. Something doesn't look right to me,
but I can't see the circuit clearly enough (too many components
obscuring the PCB). I don't think I can help you without a circuit
diagram.
Franc Zabkar
Nov 30, 2012, 1:10:41 AM11/30/12
to
On Thu, 29 Nov 2012 21:51:12 +1100, Franc Zabkar
<fza...@iinternode.on.net> put finger to keyboard and composed:
>>power on
>>
>>Vin ~111 V
>>
>>Vout to 0 V ~200 mV
>
>This is consistent with an open circuited series resistor. The zener
>is not shorted, as per your previous measurement.
>
>That said, I'm surprised that Vin is so high. I can't imagine that the
>zener voltage would be more than 10V, so this would mean that the
>series resistor would need to drop a lot of voltage. It seems too
>small for that kind of wattage. Something doesn't look right to me,
>but I can't see the circuit clearly enough (too many components
>obscuring the PCB). I don't think I can help you without a circuit
>diagram.
I'm wondering if there may be a series capacitor whose function it is
to losslessly reduce the supply voltage ...
C2
bridge 1uF
rectifier 250VAC
______ | | Vin
AC1 o--| |----| |----o-- R --+----+---o Vout
| | | | | |
||>| | ZD1 C
| | | |
AC2 o--| |-----------o-------+----+---o
|----| 0V
As for the zener voltage, perhaps we can guess at its value by
examining the battery charging circuit.
D1 100 ohm
Vout o---|>|---- R4 ----+-o
|
3.6V NiMH
110mAH battery
|
0V o------------------+-o
If we assume that the charging current is 11mA (mAH rating / 10), and
if we allow for a charging voltage of 4.5V, say, then Vout would be
...
4.5 + (100 x 0.011) + 0.6 = 6.2V
<fza...@iinternode.on.net> put finger to keyboard and composed:
>>power on
>>
>>Vin ~111 V
>>
>>Vout to 0 V ~200 mV
>
>This is consistent with an open circuited series resistor. The zener
>is not shorted, as per your previous measurement.
>
>That said, I'm surprised that Vin is so high. I can't imagine that the
>zener voltage would be more than 10V, so this would mean that the
>series resistor would need to drop a lot of voltage. It seems too
>small for that kind of wattage. Something doesn't look right to me,
>but I can't see the circuit clearly enough (too many components
>obscuring the PCB). I don't think I can help you without a circuit
>diagram.
to losslessly reduce the supply voltage ...
C2
bridge 1uF
rectifier 250VAC
______ | | Vin
AC1 o--| |----| |----o-- R --+----+---o Vout
| | | | | |
||>| | ZD1 C
| | | |
AC2 o--| |-----------o-------+----+---o
|----| 0V
As for the zener voltage, perhaps we can guess at its value by
examining the battery charging circuit.
D1 100 ohm
Vout o---|>|---- R4 ----+-o
|
3.6V NiMH
110mAH battery
|
0V o------------------+-o
If we assume that the charging current is 11mA (mAH rating / 10), and
if we allow for a charging voltage of 4.5V, say, then Vout would be
...
4.5 + (100 x 0.011) + 0.6 = 6.2V
Franc Zabkar
Nov 30, 2012, 1:12:48 AM11/30/12
to
On Fri, 30 Nov 2012 17:10:41 +1100, Franc Zabkar
> | | | | | |
> ||>| | ZD1 C
> | | | |
>AC2 o--|~ -|-----------o-------+----+---o
> |----| 0V
>
Sorry, C2 should be on the AC side of the bridge, not the DC side.
>I'm wondering if there may be a series capacitor whose function it is
>to losslessly reduce the supply voltage ...
>
> C2
> bridge 1uF
> rectifier 250VAC
> ______ | | Vin
>AC1 o--|~ +|----| |----o-- R --+----+---o Vout
>to losslessly reduce the supply voltage ...
>
> C2
> bridge 1uF
> rectifier 250VAC
> ______ | | Vin
> | | | | | |
> ||>| | ZD1 C
> | | | |
>AC2 o--|~ -|-----------o-------+----+---o
> |----| 0V
>
Sorry, C2 should be on the AC side of the bridge, not the DC side.
KenO
Dec 1, 2012, 1:00:42 PM12/1/12
to fza...@iinternode.on.net
Franc,
"It looks like this is open circuit.
Zener Test with Ohmmeter of Multimeter
Negative Probe on Cathode (Black Strip) ~140 K Ohms
Positive Probe on Cathode (Black Strip) ~167 K Ohms
I'm not sure what you are doing here. You should connect one probe to
one end of the zener, and the other probe to the other end. If that's
what you were doing, then you should have used the diode test function
of your meter.
power on
Vin ~111 V
Vout to 0 V ~200 mV
Redid the tests using the diode test function of the meter and got the same results.
"It looks like this is open circuit.
Zener Test with Ohmmeter of Multimeter
Negative Probe on Cathode (Black Strip) ~140 K Ohms
Positive Probe on Cathode (Black Strip) ~167 K Ohms
I'm not sure what you are doing here. You should connect one probe to
one end of the zener, and the other probe to the other end. If that's
what you were doing, then you should have used the diode test function
of your meter.
power on
Vin ~111 V
Vout to 0 V ~200 mV
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