k3bolation
- Feb 15, 2014
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- Feb 15, 2014
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k3bolation
- Feb 15, 2014
- 4
- Joined
- Feb 15, 2014
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oh Thank you Sir,
well it was in power supply circuit (AC to DC). very very simple circuit.
only transformer (big one) and 3 diodes actually, not 4 and 1 big electrolyte cap. and it has 4 output.(+ - , + - ) 1 of the outputs is connected to the (x72 x090). and what happend is my friend connect the 220V AC to one of outputs and the x72 exploded.
sorry for my English
Thank you for replying
well it was in power supply circuit (AC to DC). very very simple circuit.
only transformer (big one) and 3 diodes actually, not 4 and 1 big electrolyte cap. and it has 4 output.(+ - , + - ) 1 of the outputs is connected to the (x72 x090). and what happend is my friend connect the 220V AC to one of outputs and the x72 exploded.
sorry for my English
Thank you for replying
OK, thanks for that, the markings didn't make a lot of sense until you told us that.
What is the rated output voltage for the rail that this is connected to?
Where is the other end connected?
What is the actual size of this part (diameter and thickness)?
What is the rated output voltage for the rail that this is connected to?
Where is the other end connected?
What is the actual size of this part (diameter and thickness)?
k3bolation
- Feb 15, 2014
- 4
- Joined
- Feb 15, 2014
- Messages
- 4
PRI: 230V 50-60Hz
SEC: (pin 1-12) 12V DC 150mA
(pin 24-22) 12V AC 1.35A
the unknown capacitor was connected to pin 24 the AC output
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k3bolation
- Feb 15, 2014
- 4
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- Feb 15, 2014
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any help ??
The varistor is possibly the least of your worries at present. I assume from your previous comments that 240V was connected to the 24V output.
The device should normally operate with the varistor removed.
I will recommend a replacement varistor when I'm not using my phone, however there are some tests you need to run before you get to that stage.
The first thing you need to discover is whether the transformer survived. To do this you will need to disconnect the secondary ( or at least one connection to it) from the board. Next, get a multimeter and, on the ohms range, measure the resistance of the secondary. A good reading will be quite low, probably under 10 ohms. If this checks out OK, connect the meter leads to the secondary on an AC voltage range and apply power to the device CAREFULLY. If anything odd happens, remove the power immediately. If all is OK note the reading on the multimeter. Then turn off the power, discontent the mains, and finally the meter. Also note if the transformer is at all warm. This ts a fail if the voltage is outside the range of 22 to 27 VAC, or if the transformer gets warm (or obviously if anything odd happens)
The next step is to test the electronics. Let me warn you that even if the transformer is OK, it is possible that you will need to replace almost every component on the board. I'll talk more about that later...
The first test is to measure the resistance across each of the rectifier diodes in both directions. Any reading under 1000 ohms, or one which does not slowly increase to over 1000 ohms indicates a fault.
If this is OK, then reconnect the transformer to the board, connect the multimeter across the main filter capacitor on a DC voltage range and CAREFULY apply power. If nothing bad happens, read the voltage on the multimeter and remove power, disconnect mains, then remove the meter. Finally check the diodes and the regulator to see if they have gotten at all warm.
Report all of your findings but remember to go no further if any step fails.
The device should normally operate with the varistor removed.
I will recommend a replacement varistor when I'm not using my phone
, however there are some tests you need to run before you get to that stage.The first thing you need to discover is whether the transformer survived. To do this you will need to disconnect the secondary ( or at least one connection to it) from the board. Next, get a multimeter and, on the ohms range, measure the resistance of the secondary. A good reading will be quite low, probably under 10 ohms. If this checks out OK, connect the meter leads to the secondary on an AC voltage range and apply power to the device CAREFULLY. If anything odd happens, remove the power immediately. If all is OK note the reading on the multimeter. Then turn off the power, discontent the mains, and finally the meter. Also note if the transformer is at all warm. This ts a fail if the voltage is outside the range of 22 to 27 VAC, or if the transformer gets warm (or obviously if anything odd happens)
The next step is to test the electronics. Let me warn you that even if the transformer is OK, it is possible that you will need to replace almost every component on the board. I'll talk more about that later...
The first test is to measure the resistance across each of the rectifier diodes in both directions. Any reading under 1000 ohms, or one which does not slowly increase to over 1000 ohms indicates a fault.
If this is OK, then reconnect the transformer to the board, connect the multimeter across the main filter capacitor on a DC voltage range and CAREFULY apply power. If nothing bad happens, read the voltage on the multimeter and remove power, disconnect mains, then remove the meter. Finally check the diodes and the regulator to see if they have gotten at all warm.
Report all of your findings but remember to go no further if any step fails.
Travmochine
- Jan 30, 2016
- 1
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- Jan 30, 2016
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- 1
Hello, I just joined this forum because I have what looks like is the exact same component the OP was asking about. It is in a crossover for the door speakers in my car stereo. It did not blow up, but the leg on one side is broken and no longer connects to the circuit board. I thought it was a capacitor and picked up something that I thought would work at Radio Shack but it appears to not be the correct component. This thread indicates that it is a MOV.
I am not familiar enough with electronics to identify what the markings mean to guide me to find the correct component. I checked the link that *steve* posted and the list of MOVs there do not seem to correspond with any of the numbers on my component. Is it possible to get a link to somewhere that has this exact component or at least meets the same specs that I assume the markings indicate I need?
Basically, I need a link that tells me buy this part.
I am not familiar enough with electronics to identify what the markings mean to guide me to find the correct component. I checked the link that *steve* posted and the list of MOVs there do not seem to correspond with any of the numbers on my component. Is it possible to get a link to somewhere that has this exact component or at least meets the same specs that I assume the markings indicate I need?
Basically, I need a link that tells me buy this part.
Back to the power supply!
There are 5 diodes think I see. Four are in the little round black block next to the green connectors. One is on the board next to the transistor. Looks as if this diode could be a Zener to set a stable output voltage.
Since the gubbins exploded, it may have allowed excessive voltage to get into the rest of the circuitry but there is no reason to try to see if the psu will work without the MOV.
There are 5 diodes think I see. Four are in the little round black block next to the green connectors. One is on the board next to the transistor. Looks as if this diode could be a Zener to set a stable output voltage.
Since the gubbins exploded, it may have allowed excessive voltage to get into the rest of the circuitry but there is no reason to try to see if the psu will work without the MOV.
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