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Downwind

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Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 10:57am 08 Jul 2010

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Hi Bob,

Im a little confused, 100 amp at 240 volt is 24,000 watts per phase??

Same with your solar and wind inputs, you must have discovered the forth law to energy.

To do somewhere near what you want it will require one of the multi loggers i am working on that will allow up to 10 adc input channels and 4 digital channels.

Once the data is read in from the multi channels then it can be outputted wirelessly to a receiver on the computer and logged there.

Thats if a good enough wireless link can be established due to the operating conditions you have.

It will require Gordons software to log the data as it is the only logging software that can handle this many channels in one package.

As for the blinking Led.........What led?? (crystal ball from sheweng china is broken....cheap rubbish??)

Pete.

Sometimes it just works

oztules

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Joined: 26/07/2007
Location: Australia
Posts: 1686

Posted: 11:33am 08 Jul 2010

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The blinking LED is simply the safety indicator that the nuclear power station Bob has tucked away under the snake in the shed is going Chernobyl.

Got my crystal ball from the reject shop.

.........oztules

Village idiot...or... just another hack out of his depth

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 12:21pm 08 Jul 2010

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Hi Pete

Sorry about the Cat, the led is on the practice doover for the picaxe, the snake lives in the shed with its family keeping rats mice and the faint hearted out of the shed, it likes warm spots like the battery charger to sleep on.

As for the nuclear power station, that is in development, as I have been working toward a grid feed income seeing as the super died in the collaps, in the recession we never had, what,s left of our super would get us started towards that, the return on the GTI system is close to 30 % if self administered and tracked instead of fixed panel installation.

I have 42 acres to set up on and seeing as they have revalued it so I lost most of my pension, I decided to try to make use of some of it.

Advantages:

No workers just wife and I to run it.

Plenty of room for solar panels without compromising other things.

310 days a year good sunlight.

Workshop to make most parts required.

100 amp three phase power line into workshop.

10 year contract by energex at 50 cents kw tied to inflation.

Wind not so good, but OK with a suitable mill design.

Disadvantages:

AIDS {acute income deficiency syndrome}

Lot of work.

Re format of super fund to private management.

Insurance for damage and Public liability.

Murphy Law.

Others I haven't thought out yet.

Tell me I am stupid and I will agree with you but, but it's something I enjoy doing and might help the environment a bit. The amps I quoted are the maximum I can feed without re doing the underground power mains on the property.

The plan is to get going with a 20 kw system and add on from there using funds from super. Expanding to full potential if it proves to be a viable investment with income from the project.

All the best

Bob

Foolin Around

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 01:19pm 08 Jul 2010

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Hi Bob,

for the investment you have described, I think you need a commercial logging system. At the end of the day, you are talking about 240VAC stuff, and there are plenty of kWh meters out there. These would be totalling meters.

You will have no recourse for complaint, as the utility will only pay on the readings from their own meters.

You may be able to do a deal with the utility and get access to the 90 day logging built into the smart meters.

The CurrentCost meters measure 3phase, and the CC128 are wireless and can have up to 10 remote transmitters, and each can be up to 3phase. I have a CC128, with 2 transmitter modules, measuring 6 channels.

The power levels you are talking about are difficult to comprehend, and are even more than I have been simulating at 100A at 100V for 8 channels. It does not take long before the data becomes unmanageable with a logger.

What you are notioning towards is power station size.

Gordon.

become more energy aware

VK4AYQ
Guru

Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 02:18pm 08 Jul 2010

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Hi Gordon

They are installing a 100 amp 3 phase meter as the feed in meter, they won't allow me access to the output of the wireless part of it, I have the analogue instruments to monitor, and a 3phase meter for feed recording separate to theirs, more for the interest of it, as fighting with them is a waste of time, they have a service where you can get a recalibrate on their meters if you suspect any funny readings.

The size will develop but its best to make sure that all instruments don't need replacing when more tracker units are added.

I am aiming for 200 kw a day for the initial system, with 5 x 3.5 kw trackers, and the commercial supplied one fitted to the shed roof 20 kw rated, as I get the bigger trackers going those panels will be shifted there. That will be the limit of available super funds, anything past that will have to be from earnings.

I want a logger from the interest in it rather than anything else, it could be set to run on 5 or 6 inputs and is just a way of documenting performance and picking up on trends, as if I want to do more, the paper trail will be handy, the other reason is that the project I was doing a bit on prior to the financial crash looks like being reinvented as a solar farm so will be handy to document for that.

All the best

Bob

Foolin Around

neil0mac
Senior Member

Joined: 26/12/2009
Location: Australia
Posts: 210

Posted: 01:54am 09 Jul 2010

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From what I've read in recent weeks, 20KW will be the new NSW maximum feed in as well.

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 02:37am 09 Jul 2010

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Hi Neil

Qld is 30 KW for private setup at 50 cents KWH.

All the best

Bob

Foolin Around

Downwind

Guru

Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 03:26am 09 Jul 2010

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Hi Bryan,

You said [quote]I do have a few LM7809's in the shed so no 9 volt batteries needed and these will make for bery cheap displays. [/quote]

I hope you realize that with using a voltage reg with these sorts of meters you CAN NOT monitor the battery that the voltage reg is supplied from.

Or in other words the meter cannot read its own power source even with the lm7809.

The magic smoke exscapes real fast if you do try to connect the probes to the supply battery.

Pete.

Sometimes it just works

Downwind

Guru

Joined: 09/09/2009
Location: Australia
Posts: 2333

Posted: 07:57am 09 Jul 2010

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HI Oz,

Had another thought on your idea of using a multimeter for a wireless display.

Why destroy the meter to start with and just use the meter intact to read millivolts on a pwm output.
It would require driving a NpN transistor off the pwm output and use supply voltage to get a high enough resolution i am guessing.

It would not be as pretty as a neat self contained meter/circuit but should be functional.
The tricky part would be to calibrate the pwm to match a linear output equal to battery voltage.

Sounds like a good project to blow the cob webs off your proto board and put an end to jungle bells (or are you saving that for next xmas).

Pete.

Sometimes it just works

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 11:13am 09 Jul 2010

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Hi Pete, just lost a lengthy reply to cyber space, so here is an abridged version.

Drive a totem pole output, instead of the single transistor.

Linear output, with a single cap and resistor. 0V@0%PWM to 5V@100%PWM, and linear between. Easy calibration with a single load resistor to ground.

as long as the meter resistance is an order of magnitude greater than the source resistance, linearity should be maintained, with relatively easy calibration with a single pot across the filter cap. Most multimeters ar 10-100Mohm, so I don't see too many problems with the filtering to give a smooth output either.

Linearity is the key component.

Gordon.

become more energy aware

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