Fusing a Battery Supply?

[mourip]

Hi,

Have any of you who have put one of the various T-Amp flavors into a new chassis, and used an SLA battery, added a fuse to the supply?

Thanks,

Paul

 

[Pano]

Yes, I have. IAnd have never blown a 2 amp fuse, but you could use 3A if you thik 2 is too small.

A fuse is a good thing, just don't make it too big.

 

[dnsey]

I'd considera fuse essential - as near as possible to the battery. Thre's a lot of energy stored in even a small SLA at low internal resistance, quite enough to start a fire under fault conditions.

 

[mourip]

Thanks for the replies. Since no one ever mentions it I had assumed that folks did not consider it necessary with a battery.

I already had one mishap with my modded T-Amp. I inserted the battery charger adaptor into the chassis female mount and it bent the hot pin to the chassis. The result was that I let a lot of smoke out of the amp and the little battery pumped its heart out in a brilliant display of excess. Luckily the internal wiring acted as a large low value resistor and bought me enough time to yank the adaptor out before a real fire started. The amp board was unharmed.

Fuses are good...

 

[gfinlayson]

Lead acid batteries can discharge a huge amount of energy in a very short time.

There are lots of accounts of accidents occurring with vehicle batteries and spanners. The average vehicle battery can deliver several hundred amps when shorted making it a very effective DC arc welder.

 

[pburke]

I recently taught my kids about how strong battery current can be by shorting out a small 7.2aH SLA battery with a piece of CAT5 wire - instant smokage and red-hot melting copper...

I use a 5amp fuse in my battery powered DDDAC, which draws about 1 amp - it has saved a few components quite frequently. Just last week I bought a new box of 5amp automotive fuses. I can't find them any smaller, but I'm putting this fuse only in there for the "bonehead mistake protection"

Peter