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RAPS Backup

(21 posts) (9 voices)

Started 8 years ago by Wattagan
Latest reply from Lance

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Wattagan
Member

Hi all,
Just joined this forum. Previously an ATA member and Renew subscriber but not currently.
I used to manufacture a range of DC Generators for direct battery charging but similarly not currently doing so.
However I do have a few units and various components left over and would like them to go to the sorts of people who might use them as intended.
Tried listing them on eBay but very difficult to access the right people and to explain exactly what it's all about.
At least here maybe I'm preaching to the converted. Hopefully.

Anyhow, if anyone is interested in DC direct charging I'd be happy to help out where I can.

Posted Sunday 4 Dec 2011 @ 10:07:21 am from IP #
cava
Member

Where are you based?

Posted Sunday 4 Dec 2011 @ 1:16:41 pm from IP #
wlb
Member

Hello Mr.D

You helped me out 5 or 6 years ago with some very helpful advice on direct charging system for my old Lister. We were talking about one of your Thyn controllers. I never did go down that path as by the time I was ready PVs had dropped in price significantly so I added more, thereby significantly reducing dull day diesel running time.

This meant that generator efficiency was not so important anymore (1 jerrycan per month) so I stayed with the remote genset sending 240Vac to the distant battery charger and batteries. The energy loses don't really show up in the fuel consumption anymore. Nevertheless, direct charging is a very elegant way to provide back-up. It overcomes most of the shortcomings of your typical AC powered battery charger. Unless you buy an expensive charger, the output available is often not what the specs claim and charging control is not good. When you think about it, it's a very roundabout way to charge a battery. With direct charging, it's straight for the engine into the battery. Nice and neat.

Warwick

Posted Monday 5 Dec 2011 @ 3:44:52 am from IP #
rockabye
Member

That's pretty much my approach also. I'm buying another 1kWp of solar modules tomorrow for $1900 to upgrade my existing 380Wp battery backed system. May grab some more while prices are low next year.

I will probably also pick up a genset with sinewave inverter as the 'last resort' backup in the cyclone season. I did have an ex army DC charger but sold it to someone who needed it more than me during the last big wet.

That said I am a fan of DC gensets.

Posted Monday 5 Dec 2011 @ 4:44:17 am from IP #
franks
Member

Now days I rather spend $500 on a cheap 2.5kVA petrol Genset, and spend $3000-4000 on extra PVs. for backup.
Spending $5k on a Yamnar Genset for back up, your better spending the $5k in larger PV array, and get the $500 Genset.

Posted Monday 5 Dec 2011 @ 6:18:00 am from IP #
Wattagan
Member

Hey nice to hear from everyone.
I didn't get any notifications from the forum that there had been any posts here so thought there weren't any till I just checked now.
Located in Hunter Valley area of NSW
Franks mentioned "$5k on a Yanmar Genset". I would be interested to know what that referred to and why it would cost that much ?
Interesting to see that people are tending to buy more panels rather than spend on backup.
But of course you still need backup sometime no matter how big your panels are so maybe the requirement is for smaller cheaper backup sets.
And of course it's always attractive to buy a portable AC generator because it can be useful around the place the rest of the time.

I have just set up a cabin I'm building to sell with 500AH batteries 500w panels and a 1500W inverter/charger and a 10kva AC diesel generator. Have done this mainly so the buyer can have an air conditioner to run only when the generator is running as this is a big selling point. Also to spend the least possible on the solar system because as builder I can't get any sort of rebate/assistance but the buyer will be able to get that to upgrade it if they want after purchase.

So even despite my DC charging leaning I have not used it in this instance myself.

In the last few weeks I have listed a couple of my left over machines on eBay but not one bid and very few watchers !! It seems that either there are no people out there who want these or don't know they are available or what they are looking at or that what they might search for is not what I am putting in my description.
So seems I can't even get rid of them that way

Posted Wednesday 14 Dec 2011 @ 9:18:18 am from IP #
wlb
Member

You should post the links to your eBay ads in this thread,
and here http://forums.energymatters.com.au/used-wind-solar/

The only reason I didn't go down the direct charging track and get one of your controllers is that my generator is so far from the batteries, it would involve laying some very expensive new cable. I was going to relocate both the batteries and the back-up gen-set so that they were virtually side by side, but that mean building a new shed.

If they were side by side now, I would still go down the direct charging path because it's so much better and much more efficient. If you have a large capacity battery bank you need to be able to push some serious amps into it at least periodically in order to maintain it properly. It's much easier and cheaper to do this with direct DC charging than with an alternator working through an AC fed battery charger. To do this properly you also need an expensive charger. Good 240V high current 3-stage chargers don't come cheap.

Posted Thursday 15 Dec 2011 @ 3:16:26 am from IP #
franks
Member

direct DC charging is fine, the only problem is a suitible alternator with external regulator to control the charging current and voltage, nowdays its not easy to find external regulator alternators, most are fixed voltage regulator built in (14.2/28.4v)

Posted Thursday 15 Dec 2011 @ 3:40:43 am from IP #
Wattagan
Member

Hi Franks,
I have found Delco Remy (often sold under many other names) alternators a good thing although I do use Bosch sometimes.
Especially the Delco 100Amp 24V Brushless units.
I run these with external regulators at 12V, 24V or 48V with no problems and have used two of them to give 100A at 48V at times (Actually 60V when charging = 6000W)

Both have built in regulators but both are easily bypassed to connect an external regulator.
The problem I have found is that an external regulator introduces more complexity and options and choices and settings which, for most users, simply complicates the situation and usually leads to things not working as intended.
Which leads to my having to FIX the problem which costs more than it's worth.
I am happy to provide all sorts of external regulators for various purposes but it's not worth it at any price if I have to provide "warranty" that everything will just work as expected by every customer in every case despite what settings they might mess with.
Unfortunately our laws don't allow me to sell a product without warranty and in these cases they only way I could do it would be to dumb the thing down to just a basic regulator with no settings and the absolute minimum of connections.

However if people who do know what they are doing want to build their own setups I would be happy to provide the Components !
Phil 02 49988183

Posted Sunday 25 Dec 2011 @ 11:09:36 am from IP #
kiwigreen
Member

Hi Guys
another newbie here from Mudgee.
I have a Listeroid CS/8 running a 5kw 240v alternator.

But, I would like the option of direct charging my 24V 1600 Ah batteries.

Wattagan do you have any suitable bits?

cheers

Posted Monday 12 Mar 2012 @ 1:31:28 am from IP #
nickbell1955
Member

Hi , i bought a direct charging unit , a chinese 13 hp diesel generator , producing 24 plus volts at 120 amp charge from a south australian battery and solar dealer . the system was a lemon .I need a 24 volt 100 plus amp direct diesel charging unit . Any commercially available product , that doesnt come from China ?

Posted Monday 7 May 2012 @ 11:46:18 pm from IP #
Lance
Key Master

Why was the Chinese unit a lemon, the engine or the alternator was the prob? It might be something easy to remedy...

Posted Tuesday 8 May 2012 @ 12:50:27 am from IP #
nickbell1955
Member

Hi the motor vibrated violently at times . it led to cracking of the safety covers , cracking of the alternator mounts , fuel spilling if the tank was anywhere near full. electronics popped out , three starter batteries getting ruined , about one every 6 weeks , a cracked muffler , 3 oil pressure switches etc . Im scared the thing will catch fire . Basically its a design that could have worked , but is basically unsafe . Im going to scrap it and try and get a refund .No confidence it will ever be safe ..Its been back and been overhauled and came back producing only 80 amps and previously was a 120 amp out put ?The dealer has given up , saying there is nothing wrong ?So im on the hunt for a new design .( Thanks for the reply )

Posted Tuesday 8 May 2012 @ 12:59:04 am from IP #
Lance
Key Master

Oh, sounds like a real piece of cr@p

Posted Tuesday 8 May 2012 @ 1:19:57 am from IP #
nickbell1955
Member

Hi about to buy some solar panels , anyone know of any good deals out there ?

Posted Thursday 10 May 2012 @ 9:56:22 pm from IP #
Lance
Key Master

Have to say there are some amazing prices around now, Low Energy Developments has some excellent deals, as do places like Rockby Electronics, although they often run out of stock.

Posted Friday 11 May 2012 @ 1:40:18 am from IP #
nickbell1955
Member

Hi , are there any ideas on what sort of solar battery charger controllers are out there , and is pwm or mppt best for a 24v 1550 amphour battery set .Looking at australian solar manufacturers 200 watt panels , and 10 of them (2000w) needs a big controller ?
Nick

Posted Tuesday 15 May 2012 @ 3:33:07 am from IP #
Taswegian
Member

I don't know if this is the most appropriate thread it's just what showed up when I searched "direct charging generators"

All I really know comes from a guy called Brian (might even be the same one in the article) who I haven't been able to contact but need to question regarding keeping my batteries topped when there isn't enough sun.

The page I have read is here: http://www.tasmanenergy.com.au/direct_charging.html

It may be interesting/helpful to some. If anyone can add more and shed further light on the subject please do.

My scenario is a shed converted to a cabin I am designing with a 12v 675 amp hour battery bank with 750w-1000w of solar panels facing near true north slightly north east (may build an extension to face true north) I anticipate worst case scenario around 100 amp hour draw over a 24hour period and when there is no sun wish to use a generator to do the washing and charge my bank back up so as not to damage my batteries.

A local called Brian has a generator hooked up to an alternator that he will run to do the washing and charge his batteries at the same time. I like this idea but need to source help to create something like this/cost it relative to the requirements of my setup.

Posted Tuesday 6 Aug 2013 @ 2:05:16 pm from IP #
Lance
Key Master

If you click the "more info" link on that page (http://www.tasmanenergy.com.au/books.html) it takes you to Tasman Energy's books page where there's a book on building your own direct charging genset. Would be worth getting as it probably covers all the mistakes likely to be made in assembling one.

We covered basic building of these units in ReNew a couple of times, most people end up using a car alternator but you are better off with a modified alternator that has permanent magnets in place of the field winding (like this one: http://www.ebay.com/itm/370856196068 ), or even a brushless DC motor like those from the Fisher and Paykel Washing machines, there are plenty of those around going for free.

Posted Tuesday 6 Aug 2013 @ 11:05:00 pm from IP #
Taswegian
Member

Towards the end of the article he mentions that his personal setup uses a permanent magnet alternator. What applications are these created for? Your ebay link was dead.

What advantages would a fisher & Paykel motor offer?

Posted Wednesday 7 Aug 2013 @ 2:15:31 am from IP #
Lance
Key Master

Tas, ebay link just needed the ) removed off the end, I forgot it does that, fixed now. Permag alternators are made for wind and hydro turbines and general generation, marine alternators etc. Anywhere you want an alternator that doesn't waste energy in a field winding really...

Posted Wednesday 7 Aug 2013 @ 4:53:45 am from IP #

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