Generators, Batteries and Inverters

Minlak

custom titis
Haha yeah I got that :)

I've been quoted $1,500 for a Redarc BCDC install - I don't have all the component details but it will cover my requirements.

It doesn't include a fold out solar panel but you can "charge from Solar and DC inputs simultaneously".
Or you could have just started with that information - Redarc is awesome stuff but you pay through the nose for it - With a lack of information on what you are getting for the install I have no comment on relative value - there is certainly the same quality items available for half the price of Redarc
 

Dales Cannon

lightbrain about 4pm
Staff member
Haha yeah I got that :)

I've been quoted $1,500 for a Redarc BCDC install - I don't have all the component details but it will cover my requirements.

It doesn't include a fold out solar panel but you can "charge from Solar and DC inputs simultaneously".
Not simultaneously, but either or.

To clarify... a bcdc25 can take 25A from a source, alternators can do this. For solar a 200W panel will supply about 10-12A at best case. An external changeover relay will provide solar in the absence of alternator feed, the new dcdc with inbuilt changeover selects the higher current input. Voltages are different too, the inbuilt mppt controller takes full solar voltage which is probably 16 or 17V, OC voltage around 21V... alternator is maybe 14V, depends on age and brand etc.
 
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HamboCairns

Thanks for all the bananas
Or you could have just started with that information - Redarc is awesome stuff but you pay through the nose for it - With a lack of information on what you are getting for the install I have no comment on relative value - there is certainly the same quality items available for half the price of Redarc
That's the answer to my original question - it's basically Hope for battery systems - amazing quality but pricey as fuck. What other brands are out there that I should be looking at? I'm sure there's loads of shite so some guidance would be useful.
 

Dales Cannon

lightbrain about 4pm
Staff member
Ahhhh, the old green option. Must be some trickery going on inside to match inputs though. Or there are two controllers. My last install was a few years ago, not up with this latest technology using sheep bladders. I know of someone who burnt out his solar controller because it was permanently connected to the aux as well as alternator feed. Back emf fried the controller gizzards.
 

Minlak

custom titis
Ahhhh, the old green option. Must be some trickery going on inside to match inputs though. Or there are two controllers. My last install was a few years ago, not up with this latest technology using sheep bladders. I know of someone who burnt out his solar controller because it was permanently connected to the aux as well as alternator feed. Back emf fried the controller gizzards.
I think they are using the term simultaneously in a shitty way - I think they are connected at the same time but only switches to Alternator when solar input is too low. I don't believe it will charge from both at the same time! I think it will choose the best charging option from the options it has connected at the same time
 

Dales Cannon

lightbrain about 4pm
Staff member
That's the answer to my original question - it's basically Hope for battery systems - amazing quality but pricey as fuck. What other brands are out there that I should be looking at? I'm sure there's loads of shite so some guidance would be useful.
I use Redarc or Victron, Korr or solar gear from a company in Hervey Bay and Fullriver or "Century" batteries. As I said you can be successful with other gear or not. Seen both. A mate set his up with quasi branded eBay stuff including battery and solar panel and it worked for maybe half the price. Others have gone with cheaper stuff and had a warm fridge after a day. I can camp in summer and not move the car for weeks and the vodka is still frosty. Which is weird because we don't drink vodka, no idea why we carry it.
 

Dales Cannon

lightbrain about 4pm
Staff member
I think they are using the term simultaneously in a shitty way - I think they are connected at the same time but only switches to Alternator when solar input is too low. I don't believe it will charge from both at the same time! I think it will choose the best charging option from the options it has connected at the same time
I will ask Stuart, they could match inputs and parallel them which would drop alternator input to match solar for that green rush for marketing.
 

Dales Cannon

lightbrain about 4pm
Staff member
Bargaining tool or expensive radiator coolant?
Cold wheel cleaner. Sake is hot wheel cleaner. A Ranger whacked his arm and hand with a tree that split, long story but he was doing it right and a hidden fault caught him out, used the vodka as icing agent and while no one was looking anesthetic. We got the track clear and all good in the end when another couple of Rangers arrived and took him to hospital.
 

DMan

shawly the least hangeriest guy on rotorburn
Not simultaneously, but either or.

To clarify... a bcdc25 can take 25A from a source, alternators can do this. For solar a 200W panel will supply about 10-12A at best case. An external changeover relay will provide solar in the absence of alternator feed, the new dcdc with inbuilt changeover selects the higher current input. Voltages are different too, the inbuilt mppt controller takes full solar voltage which is probably 16 or 17V, OC voltage around 21V... alternator is maybe 14V, depends on age and brand etc.
Question. Been a while but back to my favourite inverter vs microwave questions. From the batteries in parallel to the inverter I'm thinking 2 gauge wire to handle 120A with a 150A fuse. But what gauge wire do you need to connect the batteries together in parallel? Do you still need 2 gauge or can you go lower?
 

Fred Nurk

No custom title here
Question. Been a while but back to my favourite inverter vs microwave questions. From the batteries in parallel to the inverter I'm thinking 2 gauge wire to handle 120A with a 150A fuse. But what gauge wire do you need to connect the batteries together in parallel? Do you still need 2 gauge or can you go lower?
Given that the gauge system has smaller numbers for larger size wire, are you actually asking if you can put larger cables to parallel the batteries?
It won't necessarily hurt, but as to what the benefit is as compared to the cost, that's probably marginal. I wouldn't go smaller cables though.
 

DMan

shawly the least hangeriest guy on rotorburn
Given that the gauge system has smaller numbers for larger size wire, are you actually asking if you can put larger cables to parallel the batteries?
It won't necessarily hurt, but as to what the benefit is as compared to the cost, that's probably marginal. I wouldn't go smaller cables though.
No, I'm asking if I need to. I understand that the draw from the batteries to inverter will be huge. But to connect the 2 batteries together, what's the min gauge I can get away with?
 

cokeonspecialtwodollars

Fartes of Portingale
No, I'm asking if I need to. I understand that the draw from the batteries to inverter will be huge. But to connect the 2 batteries together, what's the min gauge I can get away with?
The cable should be sized to handle the maximum current that can flow under fault conditions before the circuit protection operates, so if your fuse is 150A then your cable must be rated higher than that.
 

Dales Cannon

lightbrain about 4pm
Staff member
No, I'm asking if I need to. I understand that the draw from the batteries to inverter will be huge. But to connect the 2 batteries together, what's the min gauge I can get away with?
Understood, given how close they are you could go smaller but I would just get 500mm more larger cable and go with that. Redarc have a decent wire size calculator on their site. Since you should be drawing + from one battery and - from the other the current flow between the batteries will be the same as inverter draw. As close as fuck is to swearing anyway.

As above^^^^^^^ biggerer than fuse.
 

DMan

shawly the least hangeriest guy on rotorburn
The cable should be sized to handle the maximum current that can flow under fault conditions before the circuit protection operates, so if your fuse is 150A then your cable must be rated higher than that.
Will do.

Understood, given how close they are you could go smaller but I would just get 500mm more larger cable and go with that. Redarc have a decent wire size calculator on their site. Since you should be drawing + from one battery and - from the other the current flow between the batteries will be the same as inverter draw. As close as fuck is to swearing anyway.

As above^^^^^^^ biggerer than fuse.
Yep, that's what I was wondering. I got the 2 gauge from that site just wasn't sure if was the same to connect the 2 batteries.
 

PINT of Stella. mate!

Many, many Scotches
In light of the umpteenth power cut round my gaff I think it's time to start looking at investing in a generator and seeing as the Search function led me to this thread and what appears to be the very handy info on the subject I've decided it's worth renaming it to cover the extra info within!

If anyone else has got any recommendations for reasonably priced petrol gennies that could be used for emergency use in a power cut, I'm all ears.
I figure in these sort of occasions there's no point trying to run anything in the house, instead the garage is the place to be.
So what sort of wattage would be required to run about half a dozen lights, a fridge and a few electrical gadgets (TV/Stereo, chargers for phones etc.)?
 
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