Why not a use a resettable circuit breaker instead of a fuse .
Resettable 12V 80A Automatic Alloy Fuse Holder Car Audio Circuit Breaker | eBay I run one very similar between my DBC and a 50a anderson plug on the rear[wink11]
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Why not a use a resettable circuit breaker instead of a fuse .
Resettable 12V 80A Automatic Alloy Fuse Holder Car Audio Circuit Breaker | eBay I run one very similar between my DBC and a 50a anderson plug on the rear[wink11]
You'd be drawing that from the house batteries, surely.Quote:
Originally Posted by muddy
The connecting cable is usually to keep the house batteries charged whilst driving. A few amps is ample.
Think about it. What is the size of the cable from the alternator? 4mm2?
Voltage is supplied, current is taken, it's a capability. More to the point though it's about voltage drop at high current load.Quote:
Originally Posted by Mick_Marsh
The bigger the cable cross section area the less the voltage drop and the greater the efficiency in power transfer from the vehicle to the trailer and the more efficient running of high power devices. A flat trailer battery will never charge properly via small diameter cable as the voltage drop in delivering power to it is too great. ie. If you've got a dead flat aux. battery in the trailer you can drive all day with 5 metres of 6 mm automotive cable (actual 4.5 mm sq) between it and the vehicle battery/alternator for bugger all result. As cable size increases losses decrease at an exponential rate ie. doubling the cable size quarters the power loss to the aux battery and allows the charging voltage to reach a level where it can effectively charge the trailer battery. DC-DC chargers were designed to help overcome this limitation and do it well when used appropriately but do nothing for overall power transfer for a high current load. As I said "there's no such thing as cable that's too big" :)
Deano :)
The bigger the cable, the less volt drop you have over the length.
And as the battery (we're talking lead/acid here) charges, the current reduces, therefore, the voltage drop in the cable reduces.Quote:
Originally Posted by Milton477
As the current approaches zero, the voltage drop approaches zero, and you get full voltage at the battery terminals.
You size the cable accordingly.
case where using higher currentQuote:
Originally Posted by Mick_Marsh
I have a similar set up on the back of the puma with 175 Anderson plug and a 50 Anderson (2inch of cable between ) and when we have storms like at present we may loose power to house --as a result no water (PUMP) or refrigeration making it easy to get the inverter plugged in and all's good at the same time mindful of the battery volts .Then see if the generator is necessary from shed
the size of cable between alternator and battery is also a limiting factor for charging
Hi again John, there is a simple fix and it will not effect your system’s operation.Quote:
Originally Posted by John_D2
replace the 80 amp fuses with 60 amp fuses, job done and everything will then be operating within safe perimeters.
I use 50 amp auto resetting circuit breakers for that little extra safety and never had a problem.
I’ll keep it in mind. ThanksQuote:
Originally Posted by rangieman
Just a bit curious now. In a perfect world with the moon & planets aligned, how much current could you run between a dual & 3rd battery that’s 8-10m away?Quote:
Originally Posted by drivesafe
Depends on the load.Quote:
Originally Posted by John_D2
Dead short, 630mm2 cable, infinite power source, about 770A.
Dead short, 25mm2 cable, 80A alternator, 80A.
Fully charged battery, 1mm2 cable, 80A alternator, 0 to 13A