Epson ELP 7200 Projector Power Supply Help

[Dylan]

Hello, all.

I have recently acquired an Epson ELP 7200 LCD Projector with a bad
power supply. I had it assessed at an authorized repair shop and they
just said the power supply was bad.. and estimated $300+ for parts
(the PS) and $250 for labour to fix it.

I've pulled the unit apart and inspected the power supply and I can't
seem to find anything visually wrong with it. I've tested with a
Voltmeter where the power supply provides power to the main circuit
board and some of the lines have what seems to be reasonable voltage
(others do not.. but I'm no expert).

I got a hold of the Service Manual thinking/hoping it would provide
enough details for me to properly assess myself what is broken.. but
no such luck. The service manual was next to useless.. only providing
information on how to coomunicate through the serial port with a
correctly working projector. No help on troubleshooting a currently
defective one.

I've been trying to find information on possibly how to fix a power
supply but mostly find advice to not even try because of the
potentially lethal voltage stored up.

Another thought was that I could just swap out the power supply with
another one and not worry about aesthetics or mobility. It is
difficult to figure if this is possible since I don't know what the
correct voltages are for a correctly working unit.

What do people think? Is this a lost cause? Is there anything obvious
I can check out?

I've only gone to an 'authorized' Epson repair shop so far.. would I
have better success going somewhere that would actually try to repair
the current power supply rather than just throwing it out for a new
one?

The chance that I could have a working LCD projector and watch my
movies 10 feet wide on the wall is hard to ignore. I've been a little
obsessive about this thing lately.

Thanks,
Any help appreciated.

Dylan

 

[Dylan]

jaket@surfy.net (Kyle Miller) wrote in message news:<65b66215.0308280519.bb12f25@posting.google.com>...

Don't worry about lethal voltages, those are low voltage devices.

Hmm. Combined into the power supply is a separate component that
provides power to the lamp. It has a box mounted on the IC with two
serious wires coming out of it.. and on the box itself it has a
warning and a 25kV output label.

Also on the main part of the PS itself is (what I believe to be) a
capacitor that is about an inch thich and 2 inches long. I haven't
investigated to see any numbers on the side yet.. but I was wary.

Are you sure this is a low voltage device?

It may well be worth fixing if you have the time. It could be a bad
regulator or transformer winding. Check the AC voltages at the all the
secondary points of the power supply transformer. It may only have one
voltage line problem that could be repaired or hacked. If you need to
determine the correct voltage for a suspicious voltage reading, then
check the datasheets on the ic's that use the voltage further down the
circuit path.

Alright, thanks for the info Kyle. I'm going to read up more on power
supplies so that I can hopefully figure out where the regulator and
transformers are on my device.

Thanks,
Dylan

 

[Stefan Huebner]

Hmm. Combined into the power supply is a separate component that
provides power to the lamp. It has a box mounted on the IC with two
serious wires coming out of it.. and on the box itself it has a
warning and a 25kV output label.

Also on the main part of the PS itself is (what I believe to be) a
capacitor that is about an inch thich and 2 inches long. I haven't
investigated to see any numbers on the side yet.. but I was wary.

This is probably the primary side filter cap, something of
fewhunderd-uf's and 400V+ size. No low volts actually...

Are you sure this is a low voltage device?

He isn't obviously sure about what he's writing...

It may well be worth fixing if you have the time. It could be a bad
regulator or transformer winding. Check the AC voltages at the all the
secondary points of the power supply transformer. It may only have one

....it would be quite hard to simply "check the voltages" of a switch
mode power supply.

 

[Dylan]

mail.stefan.huebner@gmx.de (Stefan Huebner) wrote in message news:<3f4f3618.10619421@news.t-online.de>...

Hmm. Combined into the power supply is a separate component that
provides power to the lamp. It has a box mounted on the IC with two
serious wires coming out of it.. and on the box itself it has a
warning and a 25kV output label.

Also on the main part of the PS itself is (what I believe to be) a
capacitor that is about an inch thich and 2 inches long. I haven't
investigated to see any numbers on the side yet.. but I was wary.

This is probably the primary side filter cap, something of
fewhunderd-uf's and 400V+ size. No low volts actually...

Are you sure this is a low voltage device?

He isn't obviously sure about what he's writing...

It may well be worth fixing if you have the time. It could be a bad
regulator or transformer winding. Check the AC voltages at the all the
secondary points of the power supply transformer. It may only have one

...it would be quite hard to simply "check the voltages" of a switch
mode power supply.

Alright. Other than some obviously bad advice, and then a message
agreeing that it was bad advice, no other messages. Anybody else have
any pointers or real words of wisdom for me and my power supply
dilemma?

Any help appreciated!

Dylan

 

[Chris]

The power supply is also the ignitor and ballast for the lamp. The ignition
voltage can be upward of 20KV or more but that's only to ignite the lamp.
Unfortunately with these supplies, it's usually the ignitor that is the
problem. On this unit, I believe it's that little black or white box made by
Philips. Forget about getting it unless it's salvaged. The part was made
specifically for Epson. If you're getting your basic supply voltages to the
digital circuits (5V, 12V, etc.) then chances are it's the ignitor that's
bad.
-Chris

"Dylan" <dylan@warmbrain.com> wrote in message
news:b6859748.0308280944.340a422@posting.google.com...

jaket@surfy.net (Kyle Miller) wrote in message
news:<65b66215.0308280519.bb12f25@posting.google.com>...
Don't worry about lethal voltages, those are low voltage devices.

Hmm. Combined into the power supply is a separate component that
provides power to the lamp. It has a box mounted on the IC with two
serious wires coming out of it.. and on the box itself it has a
warning and a 25kV output label.

Also on the main part of the PS itself is (what I believe to be) a
capacitor that is about an inch thich and 2 inches long. I haven't
investigated to see any numbers on the side yet.. but I was wary.

Are you sure this is a low voltage device?

It may well be worth fixing if you have the time. It could be a bad
regulator or transformer winding. Check the AC voltages at the all the
secondary points of the power supply transformer. It may only have one
voltage line problem that could be repaired or hacked. If you need to
determine the correct voltage for a suspicious voltage reading, then
check the datasheets on the ic's that use the voltage further down the
circuit path.

Alright, thanks for the info Kyle. I'm going to read up more on power
supplies so that I can hopefully figure out where the regulator and
transformers are on my device.

Thanks,
Dylan