which size of fuses ?? (1 Viewer)

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Bart

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Jun 4, 2016
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which size fuses should i install in the following electrical connections.
1. Van battery >> 60 amp B2B charger , using 25mm2 cable over a 4 meter length ( also is 25mm2 cable heavy enough? i used it in my last van for the same purpose and it was fine , but it was over a shorter distance of 2.5 meters )
2. 300W of solar via standard 2.4mm2 cable ( aprox. 2 meters ) >>> Victron solar controller
3. 200W of solar via standard 2.4mm2 cable ( aprox. 2 meters ) >>> Victron solar controller
4. leisure batteries >>> 1500W pure sine inverter ( Dual input cables using 2 x 25mm2 cables , over a distance of 0.5 meters )
 

Lenny HB

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Cable sizes for B2B and inverter are OK, Solar cables best to use at least 4mm sq preferably 6mm sq.

Fuses B2B, 80 amp, Inverter 200amp, solar doesn't need fusing.
 
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Bart

Bart

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Cable sizes for B2B and inverter are OK, Solar cables best to use at least 4mm sq preferably 6mm sq.

Fuses B2B, 80 amp, Inverter 200amp, solar doesn't need fusing.
Thanks Lenny very much :) , i got the solar measurements from the solar panels spec sheet , it said 14 awg and goolge told me 14 awg is 2.5mm , solar panels are : https://www.ebay.co.uk/itm/12545545...d=link&campid=5338547443&toolid=20001&mkevt=1
in my last MH i never had a fuse in the solar ,, just an isolator between panels and mppt controllers , but i seen someone else had put a fuse between the batteries and the mppt , ( at the battery end ) , so that if there was a short in the cable between the batteries and the mppt it would blow the fuse, hense why i asked what size would be appropriate :)
 
Feb 27, 2011
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Just to be clear, as a common question is what size fuse for device a or device b... The fuse is designed to protect the cable not the device. So look at what the cable is rated at and that is your fuse size.
It doesn't matter what is connected at the other end.

Fusing of the device if required should be done at the device end of the cable or within the device itself.
 
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Bart

Bart

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Just to be clear, as a common question is what size fuse for device a or device b... The fuse is designed to protect the cable not the device. So look at what the cable is rated at and that is your fuse size.
It doesn't matter what is connected at the other end.

Fusing of the device if required should be done at the device end of the cable or within the device itself.
Gromett thanks for saying this incase someone reads this and doesn't know I know this ,, that is why i listed the cable size , i just listed the appliance as i wanted to make sure the cable is also suitable for the appliances as i wouldn't be as sure on that , even though i have used a wiring calculator ^^ :)

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Feb 27, 2011
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put a fuse between the batteries and the mppt , ( at the battery end )
This is critical and should always be done, well done (y)

If the mppt develops a short across one of the output mosfets. It could easily pass more current than the cable is capable of handling. It would then become like a hot wire in your toaster.
 
Feb 27, 2011
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Gromett thanks for saying this incase someone reads this and doesn't know I know this ,, that is why i listed the cable size , i just listed the appliance as i wanted to make sure the cable is also suitable for the appliances as i wouldn't be as sure on that , even though i have used a wiring calculator ^^ :)
I wasn't aiming it specifically at you. It is such a common question and quite often people misunderstand this. So I try to post similar each time.
Hopefully I didn't offend in doing so.

Hopefully others will start repeating it so that it becomes generally known :)
 
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Bart

Bart

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I wasn't aiming it specifically at you. It is such a common question and quite often people misunderstand this. So I try to post similar each time.
Hopefully I didn't offend in doing so.
Not in the slightest Grommet , you are only being helpful and I appreciate it , thanks :)
 

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