4petedaniel Posted September 13, 2009 Share Posted September 13, 2009 I intend to install a 500 watt 12 v x 240v inverter fron the 10 amp solar panel controler which will be conectet to the 12 volt on/off switch of the campers electricial system as I can't get to the lesure battery which is in the engine compartment. and there is no cable access. My question is will I have a problem with the cable size not being big enough? Petedaniel Link to comment Share on other sites More sharing options...
colin Posted September 13, 2009 Share Posted September 13, 2009 I'm guessing you mean you wish to use the inverter to run the battery charger? Where is the charger? if in the van then can't you attach to the output of charger? Link to comment Share on other sites More sharing options...
lennyhb Posted September 13, 2009 Share Posted September 13, 2009 Yes, way too small a 500W inverter will draw about 45 amps on full load. Minimum cable size should be 8.5mm2 and you should make the connection directly to the battery via suitable fuse also if you only have a single leisure battery you should consider fitting a second one. Do a group search on 'inverters' it's been discussed many time & you should find all the info you require. Link to comment Share on other sites More sharing options...
4petedaniel Posted September 13, 2009 Author Share Posted September 13, 2009 Thanks for the tip it is as I susspected. my problem is that I can't get to the battery. and as there is a teminal on the solar panel controler for a inverter, I was hoping to use it to get a 240 volt supply for my 240v equipment but I did suspect that I would find the cables to small as they are about 2.5mm Link to comment Share on other sites More sharing options...
Guest Tracker Posted September 16, 2009 Share Posted September 16, 2009 Having just 'acquired' a 12v 600w mains inverter, does the team know whether the wiring between my two leisure batteries should be capable of handling the whole 600w ( ie 50 amps @ 12v) or whether the draw would be split between the two batteries in parellel in which case the existing 30 amp cabling should be suffice. The batteries are about 4' apart. In reality it is unlikely that a load of more than 400w will ever be applied as it is mainly for SWMBO's 350w hair styler. The things we do for love - and a quiet life! Would I be correct in assuming that it is better, as in less power drain, to run the laptop via it's own 12v to 19v 'step up' adapter, rather than via the mains inverter using the laptop's mains transformer down to 19v? Thanks. Link to comment Share on other sites More sharing options...
Brambles Posted September 16, 2009 Share Posted September 16, 2009 Tracker, you should be fine with the 30 Amp cabling. If one of the batteries fails so you draw all power from the second you have a problem anyway and would not want to use hair dryer until batetries sorted. As always, make sure you have a suitable fuse for the wiring between the batteries - 30 Amps in this case. 4 inches is not enouh to be worried about volt drop. Laptop -- from 12 volts to 19 volts. More efficient than takling up to 240 and back down again. Jon. Link to comment Share on other sites More sharing options...
Randonneur Posted September 16, 2009 Share Posted September 16, 2009 Brambles - 2009-09-16 2:14 PM Tracker, you should be fine with the 30 Amp cabling. If one of the batteries fails so you draw all power from the second you have a problem anyway and would not want to use hair dryer until batetries sorted. As always, make sure you have a suitable fuse for the wiring between the batteries - 30 Amps in this case. 4 inches is not enouh to be worried about volt drop. Laptop -- from 12 volts to 19 volts. More efficient than takling up to 240 and back down again. Jon. He said 4' (feet) not 4 inches. I always thought that with 2 batteries they had to be close together. Link to comment Share on other sites More sharing options...
Brambles Posted September 16, 2009 Share Posted September 16, 2009 "He said 4' (feet) not 4 inches. I always thought that with 2 batteries they had to be close together." Wawwwwwwww!! OOOOOOPS! Sling some heavier cable in if they are far apart and fit a 40 Amp fuse between. As the inverter will have a 50 Amp fuse or whatever then under fault conditions it could draw whatever the fuse is, so your cable should cope with that or be fused with whatever the cable can carry. Also make sure the cable is well protected physically so it wil never short to the chassis -- in event of an accident or any other reason. Best to use something like corrugated tubing but at least have it double insulated. Edit -- no they do not have to be close together but is preferrable. Heavy cable between and if you wire the ground in one direction and the Positve in the other then it balances volt drops in the cable. However when further apart you can also get the situation where one battery is warmer than the other, this is not desireable either, As the warmer battery will try to supply the energy and the cooler will charge quicker. I think I have that the right way round. Link to comment Share on other sites More sharing options...
Mel B Posted September 16, 2009 Share Posted September 16, 2009 Jump lead cable - cheap and works a treat! Link to comment Share on other sites More sharing options...
Randonneur Posted September 16, 2009 Share Posted September 16, 2009 Thanks Brambles. Link to comment Share on other sites More sharing options...
4petedaniel Posted September 16, 2009 Author Share Posted September 16, 2009 Mel B - 2009-09-16 6:00 PM Jump lead cable - cheap and works a treat! Jump leads Now thats an idea. I was about to buy a battery master at £69+ to save being stranded if my main battery was to go flat. when I saw the words Jump leads, if I carry these can I connect it to both batteries in an Emergency as they are both in the engine compartment to get me on my way? Link to comment Share on other sites More sharing options...
Guest Tracker Posted September 16, 2009 Share Posted September 16, 2009 4petedaniel - 2009-09-16 7:13 PM Mel B - 2009-09-16 6:00 PM Jump lead cable - cheap and works a treat! Jump leads Now thats an idea. I was about to buy a battery master at £69+ to save being stranded if my main battery was to go flat. when I saw the words Jump leads, if I carry these can I connect it to both batteries in an Emergency as they are both in the engine compartment to get me on my way? I don't know if it will affect a modern vehicles complex electronics but I've done this several times in the past on older vans - but you will need decent jump leads and not the Poundshop crappy ones! Cheap leads are usually aluminium and you can only screw or crimp fix them. I prefer copper cables so you can crimp and solder for a better and more heat and resistance resistant joint. I've just done a dummy run for about 10 minutes with the 350w styling blower and no ill effects or warm wiring. I used the large crocodile clamps that came with the inverter's short cables and then a mains extension lead to get the dryer to the washroom. I still have plenty of automotive 30 amp cable - would a double run of 30 amp cable between batteries carry the maximum potential 50 amps if ever it were needed which is unlikely - unless I buy some more mains powered toys? Link to comment Share on other sites More sharing options...
Guest Tracker Posted September 18, 2009 Share Posted September 18, 2009 On a slightly different note, would I be correct in assuming that it is better, as in less power drain, to run the laptop via it's own 12v dc to 19v dc 'step up' adapter, rather than via the mains inverter from 12v dc to 230v ac and then using the laptop's mains transformer from230v ac down to the 19v dc that the laptop needs? Thanks Link to comment Share on other sites More sharing options...
Brambles Posted September 18, 2009 Share Posted September 18, 2009 Brambles - 2009-09-16 1:14 PM ................. .... ... Laptop -- from 12 volts to 19 volts. More efficient than takling up to 240 and back down again. Jon. See my previous post Tracker. Link to comment Share on other sites More sharing options...
Guest Tracker Posted September 18, 2009 Share Posted September 18, 2009 Apologies Jon - another senior moment! Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.