More fuses - What size for a simple car radio

[lesweeks]

I'm fitting a pretty bog-standard, new, car radio/cd player in my old boat and I'm not sure what size fuse I should use. The instructions with the unit are obviously for car installation and simply say replace like with like!

But, of course, there is no original fitting, it's a new radio, in a box, from Lidl, designed to fit into a car which, I guess, would already have a fuse in the fuse box for a radio. I thought I'd have a look under my bonnet but the car has an 'info-audio system' which is quite a bit more than the bog standard......

Nowhere can I find spec info as to what amperage the radio draws so I'm guessing and using a 5Amp.
If anyone can say I'm right or wrong I'd appreciate a comment.

Anyone driving around in a 1990's Astra?

Any suggestions? Thanks

 

[nimbusgb]

5 Amp

 

[ukmctc]

I'm fitting a pretty bog-standard, new, car radio/cd player in my old boat and I'm not sure what size fuse I should use. The instructions with the unit are obviously for car installation and simply say replace like with like!

But, of course, there is no original fitting, it's a new radio, in a box, from Lidl, designed to fit into a car which, I guess, would already have a fuse in the fuse box for a radio. I thought I'd have a look under my bonnet but the car has an 'info-audio system' which is quite a bit more than the bog standard......

Nowhere can I find spec info as to what amperage the radio draws so I'm guessing and using a 5Amp.
If anyone can say I'm right or wrong I'd appreciate a comment.

Anyone driving around in a 1990's Astra?

Any suggestions? Thanks

3 - 5 amp.

 

[lesweeks]

Thanks guys, I'm happy.

 

[the_branflake]

Fuse 17 - 10 Amp - Radio, MFD, Instrument Panel, Glovebox Light, Electric External Mirrors

So yes less than 10amps for just the radio.

 

[macd]

You might find there's a separate circuit to preserve the unit's memory. This has a very small drain, so a 1 amp fuse should be sufficient. In order to work this must obviously remain live at all times (a slightly contentious issue), so you might wish to tap off, say, a bilge pump feed, assuming that remains live, too.

 

[haydude]

5 Amp

It depends on the radio output power. I have a 4x40 Watts and I burnt a 5amps fuse using only 2x40 interior speakers at loudish volume, so I fitted a 10amps

 

[st599]

It depends on the radio output power. I have a 4x40 Watts and I burnt a 5amps fuse using only 2x40 interior speakers at loudish volume, so I fitted a 10amps

The fuse is not there to protect the radio, it's there to protect the cabling to the radio. The fuse must be less than the current carrying capacity of the wire degraded for its installation location.

 

[Ruffles]

You might find there's a separate circuit to preserve the unit's memory. This has a very small drain, so a 1 amp fuse should be sufficient. In order to work this must obviously remain live at all times (a slightly contentious issue), so you might wish to tap off, say, a bilge pump feed, assuming that remains live, too.

On mine the current is taken from the permanent connection. The switched connection that connects to the ignition on a car, is just used for sensing.

Bit of a pain really as I connected mine to the battery meter connection which was only fused at 1 amp.

 

[lesweeks]

Fuse 17 - 10 Amp - Radio, MFD, Instrument Panel, Glovebox Light, Electric External Mirrors

So yes less than 10amps for just the radio.

Hey, Thanks for checking. No electric wing mirrors on my old gaffer!

And thanks for all the other comments folks. Much appreciated.
I've resigned myself to re-tuning each time the radio goes on as I don't want the battery drain just to maintain the memory of the one or two stations I listen to.
Les

 

[macd]

I've resigned myself to re-tuning each time the radio goes on as I don't want the battery drain just to maintain the memory of the one or two stations I listen to.

I can't put a figure on it, but the drain from the memory feed is minute...rather less than a car alarm, I'd have thought. (I daresay the bumf with the radio might tell you.) Suppose your decision largely depends how long your boat's typically left unattended.

 

[ghostlymoron]

Hey, Thanks for checking. No electric wing mirrors on my old gaffer!

And thanks for all the other comments folks. Much appreciated.
I've resigned myself to re-tuning each time the radio goes on as I don't want the battery drain just to maintain the memory of the one or two stations I listen to.
Les

Could you not just use a PP9 to power the memory? Wrong voltage I know but worth a try

 

[lesweeks]

Could you not just use a PP9 to power the memory? Wrong voltage I know but worth a try

When I get everything installed I might give a PP9 a try - can't do any harm I would have thought - and if it works, it might be worth using it when I'm on the boat for more than a day or two.

Thanks again everyone.

 

[Ruffles]

I can't put a figure on it, but the drain from the memory feed is minute...rather less than a car alarm, I'd have thought. (I daresay the bumf with the radio might tell you.) Suppose your decision largely depends how long your boat's typically left unattended.

Less that the self discharge in my experience. Though probably varies on the radio! And you get a nice flashing red LED to warn off thieves....

 

[Dave_Seager]

If you connect a PP9 to the permanent power supply of the radio it would be wise to check that it does not receive 12v when the radio is on. According to the safety instructions on non-rechargeable batteries they are liable to explode if you attempt to charge them. Although this may just be a ruse to encourage you to buy more batteries I think that I would avoid it.

 

[ghostlymoron]

Less that the self discharge in my experience. Though probably varies on the radio! And you get a nice flashing red LED to warn off thieves....

After having the radio pinched out of my Golf, I drilled a small hole in the dash and fitted a red LED. It was wired to circuit that became live when the ignition was turned off. This gave the impression of an intruder alarm and I was never broken into again. (Probably wouldn't have anyway)