90 LED Strip Replaced In Jack Garden Light Model SP14-22S
This was brought to me with the complaint that the light was found dead one day. I opened to find that the LED Strip had burnt marks at one end. In the LED driver unit, the 471K X-type cap was charred, fuse was open, four M71 (SMD version of IN4007) rectifier diodes were short and tank capacitor bulged.
Thoroughly cleaned the LED Driver unit and replaced all defective components. Used 10uF & 4.7uF 105°C caps in parallel as I was not having 15uF/450V caps. Checked and found that it was giving output. Now let us have a look at related snaps:
Following pictures will show you the Voltage output of LED Driver on load with a new strip and the current drawn:
Removed the LED strip releasing the gum using IPA and cleaned the inside thoroughly. Then neatly laid the new LED strip on the inside sides, which had sticker underneath and pressed it down, and wired it to the LED driver unit.
Then applied power and found it to be working well. Then closed the unit and allowed it to run for a few hours before giving delivery to customer. Mission accomplished with satisfaction lighting up with prominent luminance to find its way into the collection bag! (LOL)
This article was prepared for you by Parasuraman Subramanian from India. He is 74 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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Arunkant L Pandit
January 27, 2024 at 6:18 pm
Well done Sir,
Perfect repair of 22watt garden light. Led strip must have 18 series and 5 parallel smd configuration. 18x3.1V=55.8 volts and 273 mA÷5=54.6mA current through each parallel line. These 0.2watt smd led can withstand 65mA maximum current. So 54.6 mA current is well within limit.
Sir 471k cmponent is I think 07D471k MOV.
Parasuraman S
January 27, 2024 at 9:39 pm
Many thanks for your expert comments and valuable inputs.
Edd
January 28, 2024 at 6:58 am
I believe that the questioned cap is merely being a CY rated 470 pf ceramic cap and not an avalanching device.
Parasuraman S
January 28, 2024 at 12:58 pm
Well, I do not remember it now. But I believe it was a filter capacitor.
Edd
January 29, 2024 at 12:12 pm
Yes serving as an RFI /EMI suppression function.
Parasuraman S
January 30, 2024 at 7:45 am
Yes, it could be!
Yogesh Panchal
January 28, 2024 at 12:28 am
Excellent Repair! Sir
Parasuraman S
January 28, 2024 at 12:59 pm
Many thanks, dear!
Waleed Rishmawi
January 28, 2024 at 1:06 am
Neat job my friend. I am sure it got better than factory. Have a blessed day
Parasuraman S
January 28, 2024 at 1:00 pm
Yes, dear. The user informed me that it was working better than the original. Reason of course is replacement of caps. Many thanks, dear friend!
Albert van Bemmelen
January 28, 2024 at 3:17 am
I always am worried that these led lights have a limited life span. Like the solar garden lights that often start to oxidize in the outside wet weather. Without much success in fixing those afterwards.
And even a led bar that was fixed in the past stopped working again recently. Most of these lights just have a very poor design from manufacturers who only care to sell more of these. Also because they only replace a led bar in the 2 year warranty time without extending the existing warranty time that was still left. Which just tells us how bad they are.
In my experience only the 1meter20 long fluorescent tube led replacement tubes that consist out of about 88 leds on the ceiling work splendidly for many years without any given problem!
Parasuraman S
January 28, 2024 at 1:02 pm
Many thanks for your expert comments, inputs and suggestions! Your keen observation and sharing always intrigues!
Henrique J. G. Ulbrich
January 30, 2024 at 12:52 am
Sure, Albert. We are talking about programmed obsolescence. In the case of LED lights, the manufacturers have a trick: they put just little thermal paste to cool the LEDs. With this dishonest action, they profit twice: less paste means less cost in the production, and less paste means too that the LEDs will have a shorted life due to work always hot. What a pitty!
Parasuraman S
January 30, 2024 at 1:01 pm
Yes, very true. Manufacturers do R&D on such tricks too! Many reputed manufacturers too indulge in programmed failure immediately after the warranty period. I know one case where a manufacturer's service technician come and just remove one cap from the board to bring it back to life. Very crooked ways to make quick money and loot the public! What to do? There is no law for controlling such malpractices!
Imoudu.O
January 28, 2024 at 4:16 am
I'm always septical installing e-caps in parallel as tank cap especially if psb is not designed in such way by manufacturer: simply
because of phobia of failing to work.Since it works in your case,i will try it when opportune.
Thanks for sharing.
Parasuraman S
January 28, 2024 at 1:04 pm
Parallel caps as filter increases capacity of load taking. It keeps the circuit cool also. Many thanks for your comments, dear!