Comments on: TP-Link wireless access point repaired. Model: TL-WA501G

By: Felippe

Felippe — Thu, 24 Dec 2015 01:23:37 +0000

Can i change the fuse with a wire?

thanks!

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By: Naseem

Naseem — Tue, 17 Sep 2013 10:33:53 +0000

thanks dear walid.

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By: Waleed Rishmawi

Waleed Rishmawi — Thu, 12 Sep 2013 19:30:07 +0000

In reply to Gerald Musy.

Gerald: thanks for your imput.totaly agree my friend. thanks for sharing

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By: Gerald Musy

Gerald Musy — Thu, 12 Sep 2013 06:55:29 +0000

In reply to Waleed Rishmawi.

Hi Waleed,

I always appreciate your articles covering a wide range of (sometimes unusual) electronic circuits.

Regarding the fuse question, there is no simple answer. Fuses are designed to blow if the current exceeds the rated value. However, they also have a time related characteristic. Some types of fuses can withstand up to 10 times or more the rated value during a short time (slow blow fuses) while others will blow immediately if the current exceeds the rated value (fast blow fuses).

In your circuit there is a rectifier and a capacitor. We can assume that the first time the circuit is powered on there will be a peak of current for a short time until the capacitor is charged. This is what slow blow fuses were designed for and I would recommend this type.

As for the value this is pretty much a guess. In some circuits we would calculate the maximum possible current and size the fuse adding 50% of this value. On your circuit I would measure the current during normal operation (this would be an average) and add at least 100% for the value of the fuse, i.e. if the current is 200 mA I would put a 400 or 500 mA fuse. Then monitor the equipment for a while to make sure that this is OK.
Maybe someone has a more scientific answer?

Cheers,
Gerald

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By: Waleed Rishmawi

Waleed Rishmawi — Thu, 12 Sep 2013 06:33:17 +0000

Thanks Beh. I appreciate it.

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By: beh

beh — Wed, 11 Sep 2013 15:31:15 +0000

waleed
you are unique in the middle east even in the world.
beh

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By: Waleed Rishmawi

Waleed Rishmawi — Wed, 11 Sep 2013 07:06:14 +0000

Naseem: you are welcome.
yes, they are but the power adaptor for this device, is 9 vold AC. so these are for changing it into 9 DC volt.

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By: Naseem

Naseem — Tue, 10 Sep 2013 10:09:09 +0000

Hi Mr.Walid,
at first thanks for the report.
I think these access points have separate power supply which provide 12vdc, so what is the function of these 4 diodes/bridge rectifier here...?
regards,

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By: Waleed Rishmawi

Waleed Rishmawi — Mon, 09 Sep 2013 07:33:57 +0000

Jerry: my amp rate was 0.8 which is less than on ohm. there is formula that I totally forgot about. Amp=Watt/voltage= amp rate. I hope this helps.

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By: Waleed Rishmawi

Waleed Rishmawi — Mon, 09 Sep 2013 07:20:26 +0000

In reply to Jerry B.Balbin.

I am not sure if you can use 12 or 24 votls light bulb or not. actually I have not giving it any thought.I will check it out though. very good question my friend.
about the fuse, i just replaced it with the same part from the same device that I have in my shop. I keep a lot of those and use them as parts. I am not sure if there is an formula about finding the rate of the fusre out there. if someone has any information about this please let us know.
sorry I was not much of a help. thanks for the questions. I will look into them.

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