Can someone tell me if I am thinking clear .In my head from leisure battery to fuse box the midi fuse that I will be fitting is there to protect the cable isn't it .so I'm using 10mm 70amp cable was going to fit 50 amp midi fuse although all items individually come far Below 50 amp they are all fused correctly so guys is my thinking correct.hope I've made clear what I'm asking!!!
The loads are important for selecting wire size. The fuse is there to protect the wiring should more than the intended load be present, most commonly a short circuit. The fuse needs to blow well before the wiring gets damaged.
It is best to put a fuse at the power supply end of the wiring, e.g. a distribution box, you seem to be supplying a distribution box so put the fuse at the battery end.. and if connecting 2 batteries with a long wire, then fuse both ends.
50A should be OK. Do you have any high inductive loads running off the fuse? e.g. large motors
It is best to put a fuse at the power supply end of the wiring, e.g. a distribution box, you seem to be supplying a distribution box so put the fuse at the battery end.. and if connecting 2 batteries with a long wire, then fuse both ends.
50A should be OK. Do you have any high inductive loads running off the fuse? e.g. large motors
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Yes that's correct. Fuse protects the cable.
But you can always down rate the fuse.
So you could fit a 30A fuse if you felt happier... Provided that the fuse is above the max load drawn.
....
You could use that 50A midi fused cable to feed a secondary ATC fuse box down stream.
That could then have smaller fuses to distribute to your circuit's.
Post some pics of what you have got and we'll have a look.
Just after preferably.
The fuse should always be first....
The fuse should always be first....
Thats
But technically it will work.
Don't do that.
Switch the POS at the source.
That's very bad practice and basically wrong as per install code.
But technically it will work.
Don't do that.
Switch the POS at the source.
Restarting this as I have questions.
I have:
Positive side:-
Starter Battery - {16mm^2 pos/red} - [Renogy DCC50S - Renogy DCC50S output] - {16mm^2 pos/red} - 60a fuse - Leisure battery (AGM).
Negative side:-
Starter Battery conn to chassis OEM.
Chassis (under seat) - {16mm^2 black/neg} - [Renogy DCC50S] - {16mm^2 black/neg} - Leisure battery.
I'd like to add an ISO switch. Should this be under the seat or under the bonnet? I have 60amp fuses, should I add the switch in as follows:-
Positive side:-
Starter Battery - {16mm^2 pos/red} - 60a fuse - {16mm^2 pos/red} - Iso_Switch - {16mm^2 pos/red} - [Renogy DCC50S Input - Renogy DCC50S output] - {16mm^2 pos/red} - 60a fuse - Leisure battery (AGM).
Thoughts? I had read somewhere that a fuse at the starter Battery and a fuse at the DC-DC end would protect the cable.
Thanks.
I have:
Positive side:-
Starter Battery - {16mm^2 pos/red} - [Renogy DCC50S - Renogy DCC50S output] - {16mm^2 pos/red} - 60a fuse - Leisure battery (AGM).
Negative side:-
Starter Battery conn to chassis OEM.
Chassis (under seat) - {16mm^2 black/neg} - [Renogy DCC50S] - {16mm^2 black/neg} - Leisure battery.
I'd like to add an ISO switch. Should this be under the seat or under the bonnet? I have 60amp fuses, should I add the switch in as follows:-
Positive side:-
Starter Battery - {16mm^2 pos/red} - 60a fuse - {16mm^2 pos/red} - Iso_Switch - {16mm^2 pos/red} - [Renogy DCC50S Input - Renogy DCC50S output] - {16mm^2 pos/red} - 60a fuse - Leisure battery (AGM).
Thoughts? I had read somewhere that a fuse at the starter Battery and a fuse at the DC-DC end would protect the cable.
Thanks.
What are you trying to isolate? Usually you want to isolate the leisure battery from its load, so parasitic drain from usb or whatever won’t run it down. So after the fuse from LB to distribution.
Isolating the vehicle battery from leisure battery I’m not sure is useful.
My Renogy manual advises a fuse at the DCDC charger end to starter battery if you have solar, as the solar can send power through to keep vehicle battery topped up.
Isolating the vehicle battery from leisure battery I’m not sure is useful.
My Renogy manual advises a fuse at the DCDC charger end to starter battery if you have solar, as the solar can send power through to keep vehicle battery topped up.
This is useful drinfinity, as I will be using my solar suit case in the warmer months!
What am I protecting? I thought the idea of a fuse at the starter Battery was to protect the cable if anything breaks the insulation and shorts the vehicle battery.
As for the isolation switch I just wondered what others have done any why.
Thanks for making me think of why I might want to add a fuse. That's very sensible.
What am I protecting? I thought the idea of a fuse at the starter Battery was to protect the cable if anything breaks the insulation and shorts the vehicle battery.
As for the isolation switch I just wondered what others have done any why.
Thanks for making me think of why I might want to add a fuse. That's very sensible.
I might not have been clear here - I was challenging an isolating switch between starter battery and charger, and suggesting it might be better between LB and load (after fuse).
Your fuse at the starter battery is absolutely correct for the reasons you describe, and also at the charger end to LB.
The extra fuse suggested by Renogy is at the charger end going back to the vehicle battery, if you have solar.
Your fuse at the starter battery is absolutely correct for the reasons you describe, and also at the charger end to LB.
The extra fuse suggested by Renogy is at the charger end going back to the vehicle battery, if you have solar.
Ok, my loads are very low current maybe apart from the diesel heater when starting up. My loads are, usb and led lights. I might have a fridge on but only for short periods as the leisure battery is only 60aHr.
I have the Renogy supplied fuse, between the DCC50S & the leisure battery. So you recon a fuse at the starter and one just before the DCC50S?
Thanks for the help. My degree is in microelectronics so this big current stuff is not my main job.
I have the Renogy supplied fuse, between the DCC50S & the leisure battery. So you recon a fuse at the starter and one just before the DCC50S?
Thanks for the help. My degree is in microelectronics so this big current stuff is not my main job.
