My WRT54G blows its power adapter!

snipped-for-privacy@gmail.com said the following on 12/15/2005 9:01:

When you say "blew" I guess that means it got real hot, maybe some smells and smoke and then stopped working? Then the same thing happened again?

Firmware isn't the cause. You've got an electrical short in the router and it may be toasted.

Lance

*****

I now have about 10ea WRT54G and WRT54GS routers at customers running DD-WRT v2.3. No power adapter failures at all.

There's no connection between the internal power supply and the firmware. The WRT54G has no software controlled power managment. Leave DD-WRT running.

I have had blown adapters on other network devices for assorted reasons. I'll list a few and you see if they're applicable.

1. Input electrolytic filter capacitor leaky and causes both the capacitor and the power adapter to overheat. Officially, you should measure the current to see if it's in spec, but it's just as easy to just check if the wall wart is getting hot. If hot, it's probably working hard heating up something inside the router. Look at the V3.1 inside photo at:
   formatting link
   power supply is in the upper left corner of the unit. You don't have to open the box. Just put your hand over the area. If it's hot, it needs fixing.
2. I've seen UPS backups blow up electronics instead of protecting them. Usually, it's an out of phase switching spike when the UPS switches to/from backup power. I was blowing up hardware at one customers location until I ripped out the UPS and replaced it with a better one. I don't recall the make and model of the one that screwed up. I think (not sure) is as a cheapo TripLite or Belkin. The replacement APC SmartUPS something was much better.

Also, the power adapter should be 12VDC 1000ma. Hopefully, you're replacing it with a similar adapter. Actually, the WRT54G can use anything that works between about 5VDC and 18VDC as it has a very wide range switching regulator.

Not blow as explosion...just stopped working. I should have used the right term :)

Router is working fine with a new power adapter but I dont know how long that will last.

What do u think?

Thanks again!

I wanted to know whether I can now Re-flash my router with the official Linksys firmware without any problems?

Sure. I've gone back and forth a few times running comparisons. The trick is to WAIT almost forever when it's done BEFORE hitting the [continue] button. Just go away for 10 minutes and do something else. If you hit it too early, the flash gets trashed. Also, reset to defaults BEFORE you flash. See:

instructions. Read and follow or you will end up with a brick (like I've done twice when I was too much in a hurry).

Here's my $0.02 worth on the Power Supplies/adapters! If you have "Modded" your WRT54G to put out more power, then it has to "USE" more power. Linksys has regulated the rf power output of the stock WRT54G and like most companies, is only giving you a power supply that supplies the NECESSARY juice to power the unit at factory specifications. So, the solution would be to upgrade to a larger amp-hour capacity power supply unit if you have increased the unit's output substantially! A recent trip to my favorite Radio Shack and an overheard conversation from the clerk regarding how many replacement supplies they had sold to WRG54G owners astonished me! Over 10 in a couple of weeks! Obviously, the "scientific" method would dictate that the electrical current used by the WRT54G should be measured at the performance level (output) that you intend to operate at, then buy the appropriate aftermarket power supply. The next question that I have is: How many WRT54G units have failed due to the increase in rf output, which was not probably in their engineering standards?

snipped-for-privacy@gmail.com wrote:

IIRC, there's more than enough margin on the power supply. It's rated at 12W, and it only draws around 5-ish.

Amp-hour capacity? While you might have cranked up the output power to 20 dBm, that's only 100mW, and even at horrible efficiencies, your power supply is only going to draw a few hundred extra mW...

I've still got my test harness, and I've still got one more WRT54G V4 in stock, maybe I'll try it some day...