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Thank you for your email, Unfortunately my brother in law is quite sick at the moment and there is very little he can do however when he gets betterwe will take your suggestion on board and see what we can do. I had thought of that but was thinking of using galvanised steel angle iron but ruled that out as the cost was very high after you bought the material. but we are also looking at setting up a solar system to supplement the wind generator.
Again thank you for your input to the forum and I am glad that you found the forum interesting
limited greenie
I hope your brother makes a full recovery, it's no fun being crook, and thank you for those words of welcome, TA muchly.
Actually, my initial reason for posting was to ask everyone on here, for advice.
If this is thought it should be in a seperate forum please let me know and I will see about doing it.
Sooooo here is the reason for my post.
*******************
My brother Stan, is a carpenter by trade, he has been involved as a manual arts teacher with the Redeemer Lutheran College for about 30 years, he retired last year.
A few months ago, he was approached to undertake a fairly large maintenance position at Gabon Lutheran Hospital on Kar Kar Island off the coast of Madang in New Guinea.
The hospital buildings need a lot of work/maintenance to bring them up to scratch, I believe several new buildings need to be put up too.
The hospital it seems has the only power avaliable, they run the generator when it suits them, they do not supply power 24hrs a day, the cost of fuel in this place is very high.
OK his wife uses a CPAP machine to help her breath when sleeping at night, in fact there are hundreds of people all over Australia in the same boat, and some caravaners also use them.
This machine uses 240v ac,at 160Watts (I will double check this shortly) CPAP at milton in Brisbane, say a 12v DC to AC pure sinewave inverter is the only power that can be used as there is a CPU processer and RAM inside these machines, spikes in the power chain spoil the software.
So there is the issue of power to run the inverter, which would have to be batteries, this in turn means the batteries need to be sufficient capacity to run the CPAP for 8 hours (sleep time) out of 24 hours, so battery capacity needs to be taken into account, and they need to be recharged, after every usage, which is every night.
OK, we now have the problem, how to recharge the batteries, and with what!
Should a Generator be used? Micro Hydro, Wind gen set, or solar cells or a combination of all of those mentioned.
What type of batteries should be used? Lead acids, Gel cells, Trojans or Deep cycle units, how much capacity should be held in reserve in case of breakdowns.
Should they have a 12volt, or a 24volt system?
Should they have 1 single 12volt battery or several single cells to make up a battery or batteries.
It has been indicated to me, it would be a good idea to be able to run a laptop and a couple of fluros off the setup also.
So, I suppose he needs a system which is bullet proof, lo maintenance, as he hasnt a clue electrically, if something goes wrong.
I don't have much concrete information to go on, as Stan is up on Kar Kar Island on a fact finding mission as I post this off tonight, he arrives back in Brisbane on the weekend, I will be seeing him this weekend, so will have more info then.
OK, this is a heeeeeep of stuff, so I will throw it into the forum ring and see what "everyone" thinks.
jim
Edited by electricme 2009-10-01
MacGyver Guru Joined: 12/05/2009 Location: United StatesPosts: 1329
Posted: 04:58pm 30 Sep 2009
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I have a buddy who travels regularly on his motorcycle and he too uses a
CPAP to insure he wakes up the morning after! He runs the thing off his
motorcycle battery, I think.
I know there is some kind of 'software' inside the CPAP, but I never heard
of it being affected by power spikes. I'll see what kind of a system he
uses and get back here with that information.
Okay. I called my buddy and he said if the power source is a battery, it
can't spike unless the battery is in a car and someone tried starting the
car while you were using the CPAP.
He said when he goes "camping" he uses a car battery, which he carries in
his motorcycle trailer (it's a Honda Gold Wing MC--Big!). He said the MC
battery would not have the electrical capacity to handle the CPAP load for
8 hours. Whenever he gets near grid power, he recharges the car battery
using a small charger that plugs into a wall socket.
He confirmed that there is software inside the CPAP in the form of
chips, which do some kind of magic, but he said he doubted a power
spike would affect them as they are likely "protected" somehow.
Hope this information helps out.
Off Topic: Hey! Did you guys feel the earthquake(s)?Edited by MacGyver 2009-10-02Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas
Thank you for your reply.
Your buddy is right, the CPAP machine has a chip which runs the thing, and he has found out about battery capacity, looks like he flatened his battery overnight, but a M Bike can be kick started and it will recharge fairly quickly.
I rang and spoke to Trevor at CPAP.
He said the machines are very succeptable to spikes, so I need to put together something that will suppress them. I was thinking of putting a big battery changeover switch to swap batteries if needed, so a 16v 100 uF electro should do this nicely.
Then there is the problem of reprogramming this thing if the software becomes corrupted. Most people just take to the CPAP agent and they come back in a couple of hours and it's fixed, out where they are, they got to do all this themselves, and I don't think they have a clue about it.
Trevor mentioned, he has not heard of a CPAP machine to operate in such a way out location, he said the batteries used to power it, must be able to be recharged ready for the next night usage.
Looking through Battery seller web sites I see they recommend the cells should not be taken down below 25% percent of their capacity or they would not recharge back to 100% capacity.
He (Trevor)is quite interested, and wants to be kept informed.
I betta put my thinking cap on and start drawing a circuit and go from there.
No, I didn't feel any tremor here, but I see on the mornings news, Samoans are really suffering right now, it wont take too long before more vision makes it's way on the telly.
But last week I was one of those who went through the dust storms, I'm still blowing dust golly, the skies might be blue right now, but there is ultra thin dust in the air just sitting there, its very fine stuff, I can still smell it.
The light is very silvery and glary, the weather is just topsy turvy.
jim
KarlJ Guru Joined: 19/05/2008 Location: AustraliaPosts: 1178
Posted: 12:15pm 30 Oct 2009
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I would use a "normal" deeep cycle battery.
To keep it living for a long time I wouldnt run it down less than 50% of its rated capacity.
160W + inverter/wiring losses call it 180W/hr x 8hrs ~1440 watts you need /12 Volts =120AH, now you dont want to discharge it more than 50% so you need 240AH.
Go for broke, few days of bad weather and you'll need the extra capacity.
I'd go for 2 x 200AH batteries.
your batteries are going to cost $600 and up depending on what brand you buy.
SLA AGM is the way I'd go myself as they are maintenance free and transport readliy
(sealed lead acid absorbed glass matt)
Then I'd get the panels go for folding ones and start with 300W -call it $1500 worth.
add your inverter of choice and you have a go anywhere solution that will reliably deliver the 1400W daily.
Any more bad weather than this, throw the batteries in the back of the ute and charge them at the hospital.
You will need more panels in winter and if she has some spare time moving the panels to pick up the most sun each day would also provide upto 40% more power out of them, this is called the human tracker method and used by many campers and caravaners worldwide.
Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.
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