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[bkenobi]

I have a PowerFlash that I pulled because it was producing enough noise that it was keeping signals from being sent (as detected by XBTM).  I replaced it with a new one and it's working fine.  I *think* the module got "burnt up" by switching too many times in too short a period.  This unit was plugged into a motion sensor via a relay.  The motion sensor sent ~1600 on/off commands during a wind storm last year just prior to the module's failure.

So, What I'm wondering is if anyone has dissected one of these to see what might need replacing.  This interest is two fold.  First, these units are rather rare at the moment and expensive, so it would be nice to salvage it for some future project if one comes up.  Second, it's there and it doesn't work...so as an engineer I want to rectify the situation!

I'm going to pull it apart per the modification procedure Hans Attersjo came up with and is posted:

http://www.idobartana.com/hakb/index.htm

[Brian H]

I have never fixed a Powerflash.
My usual suspects for flakiness is power supply.
I had an RR501 do strange things. The area around the zener diode and small value resistor in the supply. Was brown and the solder looked flaky.
In my case I replaced the zener diode and main filter cap.

On the schematic from your link.
I would look around R33, ZD2 C16. Less likely D10&D11
In the power line transmitter. Maybe look around Q3 X10s choice of transistor in many units. The 2SD667 and DZ1.

[dave w]

I fixed a couple of them, but no longer find notes on the fix. I am pretty sure it was a zener in the reactive power supply circuitry. I wil try searching and Googling. I believe it was Brian H who found the original article...possibly on ido's web site.

I just saw Brians comment. ZD2 seems to ring a bell...or maybe that's just my tinnitus.

[bkenobi]

I'll check inside the unit to see if anything looks toasty.  Since this started after massive actuation cycles, i suppose a toasty component is probably to blame and may even show visible signs of the abuse!

[bkenobi]

Looks like a toasty diode near ZD2.  The schematic should show what that row of components are, but any advice on a source for these in the states? I'd normally check radioshack, but i'm guessing these will be unobtainium as far as they are concerned.

[Brian H]

Thanks for the clear photo.

I looked carefully at the PCB as your photo shows things like ZD4.
Also a 470 uf 50 volt electrolytic cap may indicate a higher voltage supply is in your unit. The schematic is showing a 1000 uf 25 volt cap.
The online schematic could be incorrect for your revision Powerflash.
I still have some Powerflashes and may try a disassembly today.

That brown area on the board is not unusual. As the heat from the diode. Causes it to change.
Schematic shows a 1N4733A Zener.
http://www.radioshack.com/product/index.jsp?productId=2049726&filterName=Brand&filterValue=RadioShack

[Brian H]

I opened two Powerflash units I have.
PF284, Date Code 02L39. Week 39 of 2002
PSC01, Date Code 04L50. Week 50 of 2004
Both are the same PCB, but completely different from the PCB your photo is showing.
My thoughts are the schematic, we found online for the Leviton 6330 is for an older hardware revision and maybe what mine are.

[dave w]

I'd normally check radioshack, but i'm guessing these will be unobtainium as far as they are concerned.

Radio Shark only has phones and 1k ohm resistors now days. I have had good luck on Ebay. Otherwise try a large electronics supplier like http://www.mouser.com/, or http://www.newark.com/.   Also if you just Google the standard P/N or even just the values i.e 1W 7.2V zener, you will get hits from suppliers.

[Brian H]

Radio Shack does stock the 5.1 volt 1 watt zener.
Though from the photo in the thread. It is very possible it is not a 5.1 volt zener as the old schematic shows.
My only semieducated guess. Is there is now a higher voltage supply for the power line transmitter and a lower voltage one for the logic circuits.
The old schematic shows the power line transmitter being run by 5.1 volts which seemed strange to me.

[dave w]

Radio Shack does stock the 5.1 volt 1 watt zener.

Nothing short of a miracle. 

[bkenobi]

I have a Vetco Supply a few miles up the road.  I was thinking of taking the unit in to see if i could get new parts and visually confirm they are correct.  It sounds as though the schematics are of little use, so using the numbers on the actual parts may be the best bet.

Btw, since it's apart anyway, is there any way to bump the output from 5v to something like 10v with a simple component swap? I assume that such a task would be much more involved, but i thought I'd ask anyway.

[Brian H]

I would not raise the 5 volts as it is probably the logic supply voltage. It is on the ones in the schematic.

With four ZD designated diodes on the PCB. One maybe for logic supply and a higher voltage one for the power line transmitter.
ZD4 near the top left of your photo. Near the metal caned coil. Is probably the 64 volt one protecting the transmitter circuit.

[bkenobi]

I'm going to stop by Vetco on the way home from work today.  I was just planning on buying the diodes listed earlier and try replacing them like for like.  My only concern is whether the schematic calls out the right diodes for my revision of the PF.  Can anyone say whether X10 changed the design so the parts listed above are not valid? The PF I have is from 2011.

[Brian H]

I doubt the parts list from the online schematic are what is in your 2011 PF.
Your photo is 100% different than my older 04L50 X10Pro PSC01 or my 02L39 PF284 Powerflash that look very close to the schematic.
Schematic shows two Zener diodes your photo shows four silk screened parts with a ZD designation.

Best to see if you can read the 1N? part numbers on the parts themselves.

[bkenobi]

I removed zd1 and zd2 in the hopes of identifying the part number on the diodes. Most of the markings were gone on one and scuffed pretty good on the other.  Best I can tell,

ZD1 = C10PH DO package
ZD2 = C1??H DO
D1 = 1N4004 DO
D2 = 1N4004 DO
ZD3 = C?1PH DO where ? Looks like a V

The date code on this unit is 11C12.  Other markings on the board are:
E257174
Mw-S-01
1052

E63636

Anyway, when i removed ZD2, one of the solder pads pulled up.  I don't know if i did it or if that was part of the problem.  I put everything back together to test even though i didn't have replacement parts.  Since I don't have full part numbers, I also thought that I would have an easier time measuring diode voltage with it installed.  Long story short, I tried the PF and found that the noise was much better.  I was getting noise of at least n.11 on my XTBM.  I'm now reading up to n.02  not ideal, but probably good enough to leave as is.