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🛡Home Security => Problems and Troubleshooting => Topic started by: apica on September 03, 2012, 02:59:30 PM

Title: SC12A Power Issue. (updated)
Post by: apica on September 03, 2012, 02:59:30 PM
My SC12A no longer receives any power from the AC Adapter. It however seems to function properly with just the batteries. Any suggestions?
Title: Re: SC12A Power Issue.
Post by: Brian H on September 03, 2012, 03:52:11 PM
You did verify the power outlet the wall wart is plugged into is working?

That wall wart supply is a special one. It has the DC supply along with the Zero Crossing Detector and Power Line Transmitter in it.
So an off the shelf unit would not work.

If it is in warranty you may have to contact X10 for a replacement and since it maybe only in the kit with a console. You may have to swap the whole thing out.
Title: Re: SC12A Power Issue.
Post by: apica on September 03, 2012, 05:15:21 PM
I tried other outlets but no luck. I purchased this unit almost 1 year ago, I'll have to check if the unit is still under warranty.
Title: Re: SC12A Power Issue.
Post by: apica on September 13, 2012, 06:08:23 PM
Seems like I'm at a lost. The folks at X10 have determined that it's the AC adapter that's blown. Unfortunately they do not supply the adapter. They are telling me I will need to buy a need device  B:(. I feel tempted to open it up and see if anything looks suspicious.
Title: Re: SC12A Power Issue.
Post by: Brian H on September 13, 2012, 07:06:43 PM
I can tell you from my tests and opening mine to tune it up.
It has a Power Supply, Zero Crossing Detector and Power Line Transmitter in it.
From a Winford Engineering BRK4P4C Breakout Board.
Pin 1 Yellow wire in connector Common
Pin 2 Green wire in connector. +DC No load from SC12 reads +18 volts.
Pin 3 White wire in connector. Power Line Transmitter On signal from SC12 to transmitter in power unit.
Pin 4 Red wire in connector. Zero Crossing Signal from Power Supply to SC12.

One easy test if you have a multimeter. The resistance between the AC Input Pins is around 280 Ohms. My spare 49-1000P from a the Radio Shack 49-1000MC version of the SC12A measured 286 Ohms. I believe the power transformer has a thermal fuse on it {not 100% on this} and if the primary pins are open. Then the transformer is bad. I actually found a spare parts list for the 49-1000P on the RS site.
Title: Re: SC12A Power Issue.
Post by: apica on September 17, 2012, 04:06:34 PM
Thank you for the much needed information Brian H. It seems like the transformer is blown. I don't know if i'll get lucky finding a replacement.
Title: Re: SC12A Power Issue.
Post by: Brian H on September 17, 2012, 04:09:16 PM
It could be a hard one to find.
I have no actual information on it but some X10 used a a special AC Primary with a tap for the Zero Crossing Detector's power.
Title: Re: SC12A Power Issue.
Post by: pseeker on September 18, 2012, 10:04:39 AM
Might be easier buying a refurb sc1200 for $49.99 at http://www.x10.com/promotions/sc1200_cln_console_2012.html?EM (http://www.x10.com/promotions/sc1200_cln_console_2012.html?EM).  If you order $60+, shipping will be free.  Look thru their dollar store/sensor promotions to add to order.   Comes with 90 day warranty for repairs/replacement.   Should you get the other unit repaired then, you can always ebay... seems to fetch around $60 used.   May not a be bad idea to have spare replacement on hand for any critical components of your security system.
Title: Re: SC12A Power Issue.
Post by: Knightrider on September 18, 2012, 07:09:05 PM
My question:  Could another power supply be used if x10 transmissions were not needed?  i.e. just the built in alarm, no flashing lights, no powerhorn, etc.
Title: Re: SC12A Power Issue.
Post by: Brian H on September 19, 2012, 06:09:04 AM
With just DC power I would say it may work for internal functions.
Not sure how accurate the clock would be if it used the zero crossing to keep closer time. Though I have no data on this as when my power fails. The batteries seem to keep the clock running.
Title: Re: SC12A Power Issue.
Post by: apica on September 19, 2012, 12:04:01 PM
Might be easier buying a refurb sc1200 for $49.99 at http://www.x10.com/promotions/sc1200_cln_console_2012.html?EM (http://www.x10.com/promotions/sc1200_cln_console_2012.html?EM).  If you order $60+, shipping will be free.  Look thru their dollar store/sensor promotions to add to order.   Comes with 90 day warranty for repairs/replacement.   Should you get the other unit repaired then, you can always ebay... seems to fetch around $60 used.   May not a be bad idea to have spare replacement on hand for any critical components of your security system.

Thank you for this information  >!. It makes sense to just purchase a refurb.  
Title: Re: SC12A Power Issue.
Post by: apica on November 27, 2012, 08:01:51 PM
I recently got back to this project and after carefully observing the pcb I discovered that one the solder contacts had become loose. I'll post up a pic later. 
Title: Re: SC12A Power Issue.
Post by: Brian H on November 28, 2012, 06:17:42 AM
Thanks for the update.
I opened mine and retuned the power line transmitter closer to the 120KHz X10 frequency.
Not that it matters as the SC12 bit the cookie. The LCD display is about 3/4 scrambled.
I am using the earlier X10 made for Radio Shack 49-1000MC Console right now.
One of its differences. The power line On Off cycle sent during an alarm is so slow NO version of Powerhorns will work with it.

Title: Re: SC12A Power Issue.
Post by: dhouston on November 28, 2012, 08:19:47 AM
Brian,

Does X10 use the same components as they use in the CM15A? There, the center tap of the power transformer primary feeds the ZC opto and there is a separate transformer for the 120kHz. See pics at...
Title: Re: SC12A Power Issue.
Post by: apica on November 28, 2012, 09:59:30 AM
Do you think these loose contacts could contribute to the no power problem.

(http://img.photobucket.com/albums/v738/XpressRacing/pcb.jpg)
Title: Re: SC12A Power Issue.
Post by: dave w on November 28, 2012, 10:08:56 AM
Do you think these loose contacts could contribute to the no power problem.

(http://img.photobucket.com/albums/v738/XpressRacing/pcb.jpg)

Yeah, I do.
Brian H will know for sure, but I see what looks to be a wire (from the transformer?) in a blob of solder, but the solder is not whetted to the pcb trace. The black wire to the lower left does not appear to be soldered to the trace either.

Definately no "end of line" visual quality inspection taking place. $0.02
Title: Re: SC12A Power Issue.
Post by: Brian H on November 28, 2012, 01:06:05 PM
Yes I very well could be the problem.
I would inspect the whole board and resolder anything that doesn't look good.

I only pried mine partially open to adjust the frequency determining transformer.
So I don't have lots of information on its insides.

I may do a more thorough examination in a week or so.
Title: Re: SC12A Power Issue.
Post by: apica on December 10, 2012, 04:32:31 PM
 :)% I re-soldered the loose contacts and power has been restored to my unit. Thank you guys for your help.
Title: Re: SC12A Power Issue. (updated)
Post by: dave w on December 10, 2012, 06:16:16 PM
Not that it makes any difference, but I wonder if this came from the new factory, or the old one. How old was the unit?
Title: Re: SC12A Power Issue. (updated)
Post by: Brian H on December 10, 2012, 07:02:21 PM
That is great news.
Thanks for letting us know it was a bad solder job from the factory.
Title: Re: SC12A Power Issue. (updated)
Post by: apica on December 11, 2012, 07:40:15 AM
Not that it makes any difference, but I wonder if this came from the new factory, or the old one. How old was the unit?
I'll assume it came from the new factory as I had originally ordered the dx7000 but received the SC12A instead. I had the unit working properly for about 4 months.
Title: Re: SC12A Power Issue. (updated)
Post by: apica on December 11, 2012, 07:41:26 AM
That is great news.
Thanks for letting us know it was a bad solder job from the factory.

Thank you for your assistance too Brian H. >!
Title: Re: SC12A Power Issue. (updated)
Post by: Brian H on December 11, 2012, 09:20:01 AM
dave w, If it was about four months old and failed just after the 90 day warranty. It was probably from the new factory and not the X10 one in China they closed.
My 1 1/2 year old one with the bad LCD display was probably from the X10 factory in China.
Title: Re: SC12A Power Issue. (updated)
Post by: dave w on December 11, 2012, 10:02:33 AM
dave w, If it was about four months old and failed just after the 90 day warranty. It was probably from the new factory and not the X10 one in China they closed.
Yes, probably means X10 has a lot of retraining to do . If we can detect a poor solder connection from a picture, the end of line QC inspector must have been sick that day. Or maybe X10 didn't pick up that option.  :'
Title: Re: SC12A Power Issue. (updated)
Post by: haminasr on April 20, 2013, 02:36:50 PM
reference to apica problem , i had mine sc1200 wall wart power adapter blown last week. this post may help others having same problem. With help of electronic guru in Australia i managed to fix the problem. resistance at ac adapter pins was 168 k ohms but this   was because red and black wires attached to adapter pins ,(going to board underneath). once  i desoldered the red and black wires from the pins , Resistance in two pins dropped to nothing (showing blown primary coil). . i opened the adapter cheked Resistance at secondary coil, with keeping the   centre pin common, right and left  showed 7 ohmes each(showing secondary coil intact).
Actually primary coil had thermal fuse which was blown , fuse is  attached to the coil on the underside which can be seen once you desolder the fat red and black wires and lift the transformer .elevated underneath the blue tape . remove blue tape with fine needle very gently not to break thin enamelled wire attached to the fuse on one side .you will see white square like thing with two legs .short these two legs with any thin wires. should  read now (on  voltmeter) Resistance of 282 ohms  across the pins of adapter.( to avoid heating damage of solder to winding of coil , i scraped the fuse top surface with scalpel(tedious job.somehow care fully exposed two wires ends,  bent them  to centre, soldered them together).better directly join two legs of fuse.please note that bypassing the thermal fuse however makes the coil unprotected from future blowing .
i have detailed pics , tried  but i couldnot insert them here. i can send directly to email if requested. please somebody help me , how to attach pics in post
  
Title: Re: SC12A Power Issue. (updated)
Post by: Tuicemen on April 20, 2013, 05:35:12 PM
i have detailed pics , tried  but i couldnot insert them here. i can send directly to email if requested. please somebody help me , how to attach pics in post
 
see topic: The Finer Art of Posting to the Forums (http://forums.x10.com/index.php?topic=10516.msg60285#msg60285)
Title: Re: SC12A Power Issue. (updated)
Post by: dave w on April 20, 2013, 06:24:18 PM
Resistance in two pins dropped to nothing (showing blown primary coil).
Nice description, but for the non electronics folks reading, don't you mean "went to infinite or open" ?