Zenith TV fried from overvoltage A32B41W

[EJohnson]

Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher inpu
voltage; someone miswired a receptical and instead of 120 volts the T
received 240V!!! Lots of smoke filled the living room when the powe
was restored.

I took the TV set apart and found two visible blown components...
1. The line fuse (Alot good this thing did to protect the circui
board!)
2. 470uF 200V Electrolytic capacitor "was bloated" (located next to th
transformer, this is what smoked)

So I changed those two out with identical replacements...still doesn'
turn on. I like to try to fix this TV myself...cheap; there are n
nearby repair shops in my town anyways. Can someone with mor
experience please tell me what else to look for and test or replace
What else in the power supply section would burn up from this incident


Thank you for any help possible;
Johnso

 

[ray13]

Assuming you didn't blow out the new fuse. You have to look for blown
copper foil paths on the circuit board. Check all the glass and
epoxy(black case) diodes.Check the value of any resistors that are
larger than a pencil eraser. There are resistors that act as fuses they
usually are low ohmic value under 5 ohms for sure and most likely
factional ohm. I suspect it is a factional ohm resistor that took a hit
and doesn't show a sign of being blown. You have to use an ohm meter to
measure them, if they check ok take one lead out and test them to be
100% sure they are good. Resistors of any size less than one ohm should
be checked in and around the supply.

Later
KC8OJU
Raymond Borowiak

 

[Tom MacIntyre]

Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher input
voltage; someone miswired a receptical and instead of 120 volts the TV
received 240V!!! Lots of smoke filled the living room when the power
was restored.

I took the TV set apart and found two visible blown components...
1. The line fuse (Alot good this thing did to protect the circuit
board!)
2. 470uF 200V Electrolytic capacitor "was bloated" (located next to the
transformer, this is what smoked)

So I changed those two out with identical replacements...still doesn't
turn on. I like to try to fix this TV myself...cheap; there are no
nearby repair shops in my town anyways. Can someone with more
experience please tell me what else to look for and test or replace?
What else in the power supply section would burn up from this incident?


Thank you for any help possible;
Johnson

I am not familiar with this chassis...linear or switching supply?

Tom

 

[EJohnson]

Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher input
voltage; someone miswired a receptical and instead of 120 volts the TV
received 240V!!! Lots of smoke filled the living room when the power
was restored.

I took the TV set apart and found two visible blown components...
1. The line fuse (Alot good this thing did to protect the circuit
board!)
2. 470uF 200V Electrolytic capacitor "was bloated" (located next t
the
transformer, this is what smoked)

So I changed those two out with identical replacements...still doesn't
turn on. I like to try to fix this TV myself...cheap; there are no
nearby repair shops in my town anyways. Can someone with more
experience please tell me what else to look for and test or replace?
What else in the power supply section would burn up from thi
incident?


Thank you for any help possible;
Johnson

I am not familiar with this chassis...linear or switching supply?

Tom

Hello; It is a switching power supply. Board# 9-2003 Date manu. 1998

I checked the diodes and resistors around the PS section and all appea
to be fine.
I remember after I changed the 470uF cap and plugged the TV back in;
saw a faint puff of smoke rise from somewhere on the board, maybe i
was electrolytic cap juice left on board from the old cap...anythin
else that would be affected? Could it be the Power Regulator I
(STR53041 "5 pin IC") or the HOT (1167-01)? Thanks; Johnso

 

[EJohnson]

A schematic for this board would be useful...where can I get one
Johnso

 

[Jeff, WB8NHV]

Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher input
voltage; someone miswired a receptical and instead of 120 volts the TV
received 240V!!! Lots of smoke filled the living room when the power
was restored.

I took the TV set apart and found two visible blown components...
1. The line fuse (Alot good this thing did to protect the circuit
board!)
2. 470uF 200V Electrolytic capacitor "was bloated" (located next to the
transformer, this is what smoked)

So I changed those two out with identical replacements...still doesn't
turn on. I like to try to fix this TV myself...cheap; there are no
nearby repair shops in my town anyways. Can someone with more
experience please tell me what else to look for and test or replace?
What else in the power supply section would burn up from this incident?


Thank you for any help possible;
Johnson

Considering that the set was accidentally plugged into a miswired
outlet and received much more voltage than it should have, I'd say
quite a bit of the power supply was damaged or destroyed. I read
another post in answer to yours that mentioned small resistors that are
supposed to act as fuses; however, when a TV gets hit with double the
normal line voltage, no amount of fusing will prevent serious damage.
I'd get an estimate on repairs first, though. If it is $200 or more,
I'd put the money into a new set. This may be a good time to look into
a new plasma or LCD flat panel, unless your set is relatively new. I
don't know if your warranty, if still in force, would cover something
like this. If you were not aware that the outlet you plugged the set
into was miswired (why wasn't a 240-volt receptacle installed rather
than a standard 120-volt one?) you may have a valid claim.


Good luck.

Jeff, WB8NHV (email addy not shown to deter spammers)
Fairport Harbor, Ohio USA

 

[EJohnson]

EJohnson wrote:
Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher input
voltage; someone miswired a receptical and instead of 120 volts th
TV
received 240V!!! Lots of smoke filled the living room when the power
was restored.

I took the TV set apart and found two visible blown components...
1. The line fuse (Alot good this thing did to protect the circuit
board!)
2. 470uF 200V Electrolytic capacitor "was bloated" (located next t
the
transformer, this is what smoked)

So I changed those two out with identical replacements...stil
doesn't
turn on. I like to try to fix this TV myself...cheap; there are no
nearby repair shops in my town anyways. Can someone with more
experience please tell me what else to look for and test or replace?
What else in the power supply section would burn up from thi
incident?


Thank you for any help possible;
Johnson


--
EJohnson


Considering that the set was accidentally plugged into a miswired
outlet and received much more voltage than it should have, I'd say
quite a bit of the power supply was damaged or destroyed. I read
another post in answer to yours that mentioned small resistors tha
are
supposed to act as fuses; however, when a TV gets hit with double the
normal line voltage, no amount of fusing will prevent serious damage.
I'd get an estimate on repairs first, though. If it is $200 or more,
I'd put the money into a new set. This may be a good time to loo
into
a new plasma or LCD flat panel, unless your set is relatively new. I
don't know if your warranty, if still in force, would cover something
like this. If you were not aware that the outlet you plugged the set
into was miswired (why wasn't a 240-volt receptacle installed rather
than a standard 120-volt one?) you may have a valid claim.


Good luck.

Jeff, WB8NHV (email addy not shown to deter spammers)
Fairport Harbor, Ohio USA

It isn't under warranty anymore and the receptical it was plugged int
used to be 120V but someone screwed up the wiring at a junction bo
(mixed the neutral with another hot) during a breaker box upgrade.

I plan to rebuild the power supply section; I just need a schemati
(free) to know the resistor and cap values. Johnso

 

[[email protected]]

Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher input
voltage; someone miswired a receptical and instead of 120 volts the TV
received 240V!!! Lots of smoke filled the living room when the power
was restored.

Who is responsible for the miswiring? You--tough luck. A
professional--luck! It's their responsibility to fix the thing.
At any rate, it appears you're going to need a pro to fix it. Call
it quits now.

David, on the Illinois prairie.

 

[[email protected]]

Hello everyone,

I have a Zenith 32" Model# A32B41W TV that fried from higher input
voltage; someone miswired a receptical and instead of 120 volts the TV
received 240V!!! Lots of smoke filled the living room when the power
was restored.

Who is responsible for the miswiring? You--tough luck. A
professional--luck! It's their responsibility to fix the thing.
At any rate, it appears you're going to need a pro to fix it. Call
it quits now.

David, on the Illinois prairie.