My 12v cigarette lighter has been changed to a usb charging port with an inline 25A fuse.
Any views on why it is 30A? Should I change it back to 15A?
Unexpected fuse in slot 3
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Alfredo
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Unexpected fuse in slot 3
I have a 30A fuse in slot 3 of my fuse box, which according to all sources I can find show it as a 15A fuse?
My 12v cigarette lighter has been changed to a usb charging port with an inline 25A fuse.
Any views on why it is 30A? Should I change it back to 15A?
My 12v cigarette lighter has been changed to a usb charging port with an inline 25A fuse.
Any views on why it is 30A? Should I change it back to 15A?
1988 Autosleeper Trooper pop top 1.9DG
2003 MG TF 135 Cool Blue
2003 MG TF 135 Cool Blue
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Mocki
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Re: Unexpected fuse in slot 3
What size id the wire ? I suspect a PO has plugged something in that blown a fuse so did the idiot thing and put a bigger fuse in ?
Steve
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1989 2.1LpgWBX HiTop Leisuredrive Camper
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1989 2.1LpgWBX HiTop Leisuredrive Camper
1988 2.1 Auto Caravelle TS TinTop Camper
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Alfredo
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Re: Unexpected fuse in slot 3
How do I measure the wire size?
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2003 MG TF 135 Cool Blue
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ZsZ
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Re: Unexpected fuse in slot 3
Put back a 15 Amp fuse. If it keeps blowing investigate further.
Maybe it was an "emergency" and just 30A fuse was handy but it is also possible that the wiring was changed beside the panel. Or the PO just left the wires as is which is bad.
If the charger fuse is 25A, then it is better to pull a new 2 mm2 wire directly from the battery.
https://www.12voltplanet.co.uk/news/cable-sizes.html
Maybe it was an "emergency" and just 30A fuse was handy but it is also possible that the wiring was changed beside the panel. Or the PO just left the wires as is which is bad.
If the charger fuse is 25A, then it is better to pull a new 2 mm2 wire directly from the battery.
https://www.12voltplanet.co.uk/news/cable-sizes.html
Zoltan
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th
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Alfredo
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Re: Unexpected fuse in slot 3
OK I have put a 15A fuse in.
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2003 MG TF 135 Cool Blue
2003 MG TF 135 Cool Blue
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cobblers
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Re: Unexpected fuse in slot 3
25A is an insane fuse choice for a USB charger. It's ten times an appropriate value! Whoever fitted this has absolutely no idea what they are doing. Replace the inline fuse with a 2A or 3A fuse.
On to your 30A fuse in the main fuse box - the VW CE1 fuse box is marginal at best and the fuses are all chosen to appropriately to protect the circuits strung off it. Under no circumstances is it a good idea to increase the amperage of any of these fuses.
You've done the right thing fitting a 15A fuse - 15A is plenty of power for everything you have on that circuit.
On to your 30A fuse in the main fuse box - the VW CE1 fuse box is marginal at best and the fuses are all chosen to appropriately to protect the circuits strung off it. Under no circumstances is it a good idea to increase the amperage of any of these fuses.
You've done the right thing fitting a 15A fuse - 15A is plenty of power for everything you have on that circuit.
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Alfredo
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Re: Unexpected fuse in slot 3
1988 Autosleeper Trooper pop top 1.9DG
2003 MG TF 135 Cool Blue
2003 MG TF 135 Cool Blue
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cobblers
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Re: Unexpected fuse in slot 3
With three USB ports in one device, a 5A/7.5A fuse would be reasonable. The specs of this charger claim it can do 45+45+18=108w max which would need a 10A fuse, but these chargers are generally well over-rated, and particularly when running off a 12V supply they can only achieve a max of 27W on each USB C PD output.
A scenario where that charger is continuously delivering maximum stated power on all three outputs at the same time is less likely than the scenario where it randomly fails internally and you have to rely on a fuse to stop it going on fire, so I would err on the side of caution and go with 5A. I have fitted dozens of very similar chargers and always use a 5A fuse.
A scenario where that charger is continuously delivering maximum stated power on all three outputs at the same time is less likely than the scenario where it randomly fails internally and you have to rely on a fuse to stop it going on fire, so I would err on the side of caution and go with 5A. I have fitted dozens of very similar chargers and always use a 5A fuse.