Battery powered DS help

[Alan Anderson]

Originally Posted by J-Mech

Well the fuse would protect against a device failure. So it would make a difference by protecting the router.

No.

Fuses do not protect devices. They protect wires from a device failure. Note that the only way to blow a fuse is to draw too much current. The only way for the router to draw too much current is for it to fail. A fuse cannot protect the router from itself.

A fuse might protect against the application of too high a voltage, but only if the device's power input was designed to survive overvoltage and to draw lots of current in the process.

[Tom Line]

Originally Posted by lcoreyl

Hmmmm... just lost SECOND router using battery power. I think we are going to start using fuses; I would recommend the same to you...

Anyone else lost a router?

We lost a protective switch earlier this year. We were using a cellphone power supply with the correct voltage rating, but a lower amperage rating. The switch tried to pull too much current, the cellphone power supply fried, and that fried the switch in turn.

It was a deperation move when we were at West Michigan and they announced they were out of DS's, and we only had 1 working port.

We'll be working on something a little more robust and easier to lug around than one of the 12V batteries...

[Al Skierkiewicz]

I believe the original IFI backup battery was 700 maHr but many teams purchased packs that had greater capacity. 1400 maHr seemed to be the norm.

The router unlikely had an electrical failure. Have you tried using the "return to factory default" procedure to load the original settings? Wall wart power supplies are rarely regulated, so electronics already have internal regulators. The WRT610N requires 1.5 amps at the power input.

Tom, I think your description is that you were using a battery from a cell phone to power the router. Or were you using a cell phone charger/ power supply to power the router. In any case, a failure to provide 1.5 amps at 12 volts nominal might have caused the router to corrupt it's firmware settings making it appear dead. The factory restore procedure or a reload of firmware may bring it back to life.

[Tom Line]

Alan, it was our sacrificial switch that died - we never killed the router. For whatever reason, we found it VERY difficult to find a switch at ratshack or officedepot that ran off 12 volts - they all seem to run off 6V.

Again - this was something done in desperation when we realized that if our last port died, we were out of the competition. We ran out the morning of to find the components. After realizing we couldn't find a switch that ran at 12V, we ran back out and got a cellphone car charger that provided .7 amps at 6 volts. We wired that into one of the 12 volt batteries to provide 6 volt power for the switch.

The car charger died, and the switch died at the same time. I can only assume the switch pulled too much amperage, fried the charger, then fried itself. It will no longer power up, so I would guess we killed the voltage regulator, though I never bothered to check.

[Al Skierkiewicz]

Tom,
It is hard to know what the output of a battery charger could be. The 0.7 amp rating could be a "peak" rating based on a pulsed output. Since the switch does not present the same load as a battery would, the charger may have put out a really strange waveform. There are a few protection devices that could be in series with the power input on the switch that may have failed, and may be replaceable if a qualified person were to open the device. In most cases, I do not recommend the use of a charger as a power supply. It seems that many devices are designed for the lower voltage with the advent of lower voltage requirements for microprocessors. 3.3 volt interface electronics are becoming common as well, hence the move to 6 volt power inputs.