Shorted Zener Diode Found In Voltage Stabilizer
This is a voltage stabilizer that is in use for my Fridge. It had failed a couple of years back and that time, it was due to dry solder and I solved it and also replaced the electrolytic capacitors, since the ESRs were in the brim. My wife reported that the Fridge was not on and when I went and checked up, there was no output from the voltage stabilizer, even though there was input. I connected the Fridge directly and it was found working well. So brought the stabilizer for troubleshooting to my workshop.
As usual, the first job is external and internal cleaning, which I did quickly. Removed the PCB and found that there was no dry solder.
The stabilizer has two PCBs, one for its power supply, which housed the rectifier diodes, smoothing capacitor and 12V regulator IC. The next board was the buck/boost section, which had two relays. The relay was getting on when switched on, indicating that the primary power supply and the relay driver circuit was working alright.
As you can see, the soldering was still intact.
I checked the semiconductors as well as the passive components and found only one 9.1V Zener leaky.
Replaced it, gave power connection and checked the outputs. The LED was lit and the output was present.
Reassembled the unit and connected it to the Fridge and found it to be working perfectly well. My wife was happy that I could fix it so soon!
Another service added to my satisfaction list, with ‘double’ effect!
This article was prepared for you by Parasuraman Subramanian from India. He is 69 years old and has more than 30 years’ experience in handling antique equipment like Valve Radio, Amps, Reel Tape Recorders and currently studying latest tech-classes conducted by Kerala State Electronics Technicians’ Association. He has done graduation in BBA degree, private diploma in Radio Engineering and retired as MD of a USA company. Presently working as Consultant to Hospital and other institutions.
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https://jestineyong.com/servicing-worldtech-car-reverse-monitor/
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ThandoSebeneleMavimbela
December 5, 2018 at 10:13 pm
tnx so much know l have learned something new
Mason Sarles
December 5, 2018 at 10:26 pm
Thank you for sharing your repair. You have to love it when the repair is simple for a change.
Thank you,
Mason
Texas
Albert van Bemmelen
December 6, 2018 at 12:54 am
Interesting article. These kind of Voltage stabilizers are completely unknown in my country The Netherlands and surrounding countries. Most likely because they are not necessary here. I remember a similar device from an article written by our friend Humberto in Cuba.
Waleed Rishmawi
December 6, 2018 at 1:26 am
Very good repair. Thanks for sharing
Mihai
December 6, 2018 at 2:01 am
Good job Sir ! Thank's for sharing !
ANGELO
December 6, 2018 at 2:51 am
WELL DONE SIR (Parasuraman Subramanian)
I HAVE A QUESTION
WHAT DOES A LEAKY TRANSISTOR OR LEAKY DIODE MEAN ?
HELLO SIR JESTINE
HOW ARE YOU ?
Jestine Yong
December 6, 2018 at 7:29 am
Hi Angelo,
I'm fine thanks.
Jestine
Parasuraman S
December 6, 2018 at 9:03 am
Partially conducting to a path which it should not, is called 'leak.' A diode should not show low resistance on checking it in reverse order. But in this case, it was showing some resistance.
beh
December 6, 2018 at 12:17 pm
Thanks for this repair report.
Arunkant Pandit
December 6, 2018 at 1:44 pm
Dear Sir,
All repair articles are very well explained by you. I am mechanical engineer but electronic repair is my hobby. I love all your articles.
Thank you for sharing your hard work.
Justice
December 6, 2018 at 4:26 pm
Good work Parasuraman, I have gained valuable knowledge with your article.
Robert Calk Jr.
December 7, 2018 at 1:22 am
Good job, Parasuraman. Thanks for the article.
Yogesh Panchal
December 13, 2018 at 6:28 pm
Good job! Sir,