EcoRenovator

EcoRenovator (https://ecorenovator.org/forum/index.php)
-   Geothermal & Heat Pumps (https://ecorenovator.org/forum/forumdisplay.php?f=10)
-   -   #2 Sanyo 24KHS72 AC/HP Install Project (Oct 2011) (https://ecorenovator.org/forum/showthread.php?t=1815)

WyrTwister 05-05-16 01:58 AM

Thank you , :-)
Wyr
God bless

Xringer 05-14-16 03:01 PM

We had about 8 days of off & on rain, then relative passed on..
Plus seems the trees are full of allergens these days. I feel like taking a nap until summer.
Feel like I'm starting from scratch again..

I decided to change the SSR(my add-on), on the off chance it wasn't working at 100%..
It was a 1000 to 1 shot, and it was a miss..

Xringer 05-14-16 03:56 PM

Quote:

Originally Posted by jeff5may (Post 49932)
Xringer,

Good eye seeing TH02. It looks to be a thermistor (probably PTC like a deGaussing coil in a crt tv) wired across that mains relay. It could be the standby power bleeder component that bootstraps the rectifier bridge with just a little power. Then again, it could be just an inrush current limiter for when the power is applied(to precharge the big caps). Either way, since it is there, you should have some current bleeding through to that rectifier bridge and PFC network (enough to get 12-15 volt standby b+ and maybe regulated 5V out of the tinyswitch).

.


I'm thinking THO2 might be the Bootstrap.. Not sure, since I have no clue, what's under the plastic box..
So, I'm thinking about tacking a 12k Ohm 5 or 10w resistor across THO2, (mains relay) just to see what happens when the 230Vac hits it.. I think 12k should allow about 20ma to flow down into the diode bridge..
That might be enough to generate some DC out of the tinyswitch.?.

What do you think? Worth a try?

I found some 5W 24k resistors.. I could solder one in and try it with very low amps,
if nothing twitched, drop another 24k on top, to make it 12k..
24000 Ohm 24K 5 Watts 5W 5 Ceramic Cement Power Resistors Qty 3 | eBay

jeff5may 05-15-16 10:18 AM

It's been awhile, so (not surprisingly) I lost track of everything. This kind of troubleshooting is best done either all in a short time or by taking lots of notes. I dunno bout you, but I didn't take no notes.

I believe you said you had AC power at the relay contacts feeding your main power switch. To test what happens, you can use a neon light across the contacts. You may have one of those outlet testers (that you poke the probes of into your receptacle sockets to check whether they are live or not) laying around somewhere. If the neon light doesn't pass enough current to make things try to operate, you could start putting shunts across the contacts too. If the neon light illuminates, something is trying to draw current somewhere.

You shouldn't need to do this if TH02 is doing what it should. Previously you measured it at 40 ohms cold. This is OK for a PTC, as it is at its minimum value when no current is passing through it. As in a degaussing circuit, when power is first applied, the PTC will send a jolt of AC down the line. Naturally, much current will flow, heating up the PTC. Its resistance then skyrockets as it heats up, pinching off inrush current after a few milliseconds.

In this circuit, as the current falls, so should the PTC resistance. The voltage value at the bridge rectifier will end up hovering at a certain value while the relay it shunts is not energized. So in this unit, it looks like that juice goes through the bridge rectifiers and D07, out the brown wire, and up to the capacitor bank. I can't tell from the photos whether the brown wire is connected straight to the bank or if it goes through the fuse in the corner. Either way, you should be able to verify that path on your working unit when the unit is in standby to compare with the dead unit. If the micro is bootstrapped through the brown wire, it should have a certain amount of DC feeding the capacitor bank in standby. When the relay contacts close, and the unit runs, that brown wire will have full DC voltage from the bridge passing through it.

Whether or not the brown wire carries start-up voltage to the micro or not, if it doesn't match the working unit's behavior in standby, this would indicate a short or open (or wonky) circuit feeding off the main B+ capacitor bank. This could be anything. Main suspects include the tinychip, the power factor IGBT, the compressor control IC, etc.

A while ago, I found a few more resources, straight from panasanyo:

ftp://ftp.panasonic.com/heataircondi...andbook_sm.pdf

ftp://ftp.panasonic.com/heataircondi...2010-v4_sm.pdf

None of these resources really dig into the control board guts, as service techs are not factory service engineers. As these boards command the big bucks refurbished, I imagine the companies who bring them back to life have the tech sheets, prints, and diagrams secured in a data vault somewhere. they probably have a detail of internet police taking down any useful service info that finds its way out of the vault. Good luck finding anything specific without being an authorized service engineer.

Xringer 05-15-16 04:10 PM

Thanks for the reply!
 
Health issues abound, bad weather, a wake & funeral and other stuff,
have delayed digging into this Sanyo mess again. Thanks for taking the time to refresh yourself. You got me reading about re-healing fuses etc today.. :D
I did not have that 2010V4 pdf.. It looks interesting.

Yeah, I just checked TH02 again, and it's 43 ohms. (both directions). Under power, there is 240 vac across it.
I guess these modern PTC devices can conduct current up to a certain value, before their resistance shoots up..
I have no way to tell if this one is allowing 200 mA to pass or 200 uA to surge pass..

It seems like after the on-surge, there isn't any current passing. Not noticeable.
Not sure what could cause a failure mode these things. Maybe a big spike?


I don't have any neon lamps that wouldn't need a very large series resistor at 240vac..
So, a 24k resistor should pass 10mA.. And if I still see no DC on the board, step up to 20 mA, and then 30 mA (last resort).

That should tell us if TH02 is a failed Bootstrap device or not..

It could also tell me if I need to get serious about buying a 1-ton Gree for the den..

Xringer 05-18-16 08:56 PM

Well, that was a dead end..
 
1 Attachment(s)
I started with one and added on another, and then another..
They got pretty hot, but the DC voltage on the large caps was under 3Vdc.
No DC going to the logic devices..
http://ecorenovator.org/forum/attach...1&d=1463622781


All times are GMT -5. The time now is 06:31 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Ad Management by RedTyger