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Jaffasoft

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Joined: 03/11/2010
Location: Australia
Posts: 102

Posted: 09:39pm 11 Dec 2012

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Hi,
I'm battling my way through making a board and connections, to batteries from a 500 watt max wind turbine, a controller, 600 watt Resister, 50 amp circuit break, 4 AWG Wiring and still not clear on a couple other things. Want to run it by a couple of you more experienced so I don't stuff things up.

This is all installing in a shipping container and the Turbine mounted on the top! Might be able to get a photo up in a while but first bit of confusing is as follows!

I've bought the resisters and the 440 Amp 10,000 Coleman Air Control Box as in this link which has all connection illustrations and explanations, Coleman Air C440 . Just still a little confused after reading the instruction leaflet sent which is the same as the link info above!

It illustrates to connect a negative "loop" wire run from the left negative in the Control Box (from the Soliniod.. I think its called.... it has a big nut coming off of it on the left side of it!), then through a Fuse, to one side of the resister then a connection from the other side of the resister down to the negative on the Battery. In the illustration in the link, this "loop" is marked all Blue!! Not RED or BLACK???

Question is?.. why is this so?... why both negatives? wont the resister need a positive to dump the load, or does the negative line coming out of the Box switch to become a positive line when it needs to dump excess power to the resister?

Daniel
Edited by Jaffasoft 2012-12-13

Downwind

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

Posted: 03:11am 12 Dec 2012

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Ok, the blue line is the main switched positive feed to the dump load. the whole dump circuit wiring is shown in blue, due to the fact it makes no difference which terminal of the dump wiring goes to what, as long as one end of the resistor connects to the battery V- and the other wire from the resistor connects to the bolt on the solenoid.

When the controller activates the solenoid V+ is switched to the dump load, completing the circuit and applying power to the dump resistor.

Pete.

Sometimes it just works

Jaffasoft

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Joined: 03/11/2010
Location: Australia
Posts: 102

Posted: 02:08pm 12 Dec 2012

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Thanks so much for explaining that out! You've even uploaded a diagram.

OK, so that is the function of the Solenoid. To Switch the blue line over to run in +Positive feed.

Jaffasoft

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Joined: 03/11/2010
Location: Australia
Posts: 102

Posted: 09:09pm 12 Dec 2012

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On connecting it all up and using batteries well undercharged and testing the whole system under wind, the controller instantly makes a shuttering noise, lights red and I'm assuming is dumping. This effect is recurring and does not seem right.

Any suggestions what might be going on here?

I thought maybee the two smaller bolts on the front of the Soliniod may have came to me from the manufacturer wired incorrectly? I am only assuming this but I do not actually know yet!

What I can say is the right small front bolt has one small wire going to the 12V+ Coil at the "top" slots, IN screw slot (the second slot in from the right at the "top"). And the left small front bolt wire goes on the left side marked 'Relay'.

Downwind

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Joined: 09/09/2009
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Posted: 11:38pm 12 Dec 2012

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Daniel,

From what you say its likely the battery you used was dead, and when the circuit switched the dump load on it dropped the battery voltage so fast it put the circuit into a ON / Off frenzy, this would also suggest the hysteresis is incorrectly set, meaning the voltage difference between when the circuit switches the dump load on, and the voltage the circuit switches the dump load off at.

The shutter noise is what we call "relay chatter" where the relay (or solenoid as you might call it) switches on and off at a fast rate, this is BAD, not what you want to do with any relay for a extended time.

The problem is the window of hysteresis settings is far to close together, for example if the circuit switched on the dump load at 13.8 volts and switched the dump load switches off at 13.6 volts, the draw on the battery would instantly drop the voltage below 13.6v meaning the circuit would switch off the dump load, then the voltage of the battery rises due to no load and the circuit switches the dump load back on ........RRRRRR-Repeating.............hence the fast on/off relay chatter you hear.........BAD!

Guessing this is a 12v system using wet lead acid batteries, try setting your hysteresis voltages to 14.2v dump load on, and 12.8 dump load off, this should give a reasonable window of hysteresis to not cause relay chatter, it should be ......CLUNK....... relay on............. waiting........ still waiting.......... CLUNK......... relay off, ..........not BUZZZZZZZZZZZZZZZZZZZ of relay on/off.

My personal view of this controller is its a poor design, this is a view others may contest, as there is those who like this method and those like me think its a poor system.

My reasons are .......... any system that dumps from the battery is a poor design i think, why spend sooooooooo long putting the energy into the battery, only to discharge the battery into heat (dump load) to make room for more energy to be put back into the battery.................total stupidity i think!!!!, as you spent sooooooooo long charging the battery why the hell waste it because its full and the mill needs to be loaded.

So your battery is full, and the voltage rises to the dump load trip point........ big deal......... all you really need to do from here is dump the energy the mill makes and leave the battery alone fully charged.
The battery still connected to the mill via a second rectifier and controls the hysteresis set points, but it allows for a narrower window of hysteresis to be set, because as soon as a load drops the battery voltage below its resting voltage the mill is switched from dumping energy back to supplying the batteries.

As i say there is a team that bats for either method, i just cant get my head around the need to waste what you spent so long to collect.

Pete.

Sometimes it just works

MOBI
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Joined: 02/12/2012
Location: Australia
Posts: 819

Posted: 12:08am 13 Dec 2012

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[quote]why spend sooooooooo long putting the energy into the battery, only to discharge the battery into heat (dump load)[/quote]

I did think that as I have been following the thread but didn't interrupt. I figured it would get to this stage soon enough.

david m

David M.

Downwind

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Posted: 12:30am 13 Dec 2012

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[quote] but didn't interrupt [/quote]

Well thats a big help? letting me do all the typing

What ever happened to the days pasted where several members would chime in with a response to a question.

It would seem "Elvis has left the building", that is sad to see compared to the collective data pool responses of past years and present members.

Pete.

Sometimes it just works

Jaffasoft

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Joined: 03/11/2010
Location: Australia
Posts: 102

Posted: 12:52am 13 Dec 2012

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Oh the old "relay chatter" that sounds an apt description, first time it came on it made a hell of a noise, nearly fell over the axe plitter. I had to do a professional job of crimping wire terminal ends

. I jumped a back two foot. Then it kept kicking in as the mill winded!

You guess correctly as a 12Volt system and the batteries are two tip found discarded Ex Telstra 6V joined in serious. Quiet possibly dead, though I'd hopped not, they were left to drain run flat on an electric pulse fence over a year ago and measure 7.79 volt at the amp meter today. I thought I would connect them on to experiment, start off with to see if this fantastic wonderful arrangement would do the deed.

I tend to agree with what I'm reading that you make sense not to discharge all the good stored energy!

I disconnected the controller immediately today and left the turbine connected directly. Since the jury is still out on this!

Edited by Jaffasoft 2012-12-14

MOBI
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Joined: 02/12/2012
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Posts: 819

Posted: 01:04am 13 Dec 2012

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[quote=downwind]Well thats a big help? letting me do all the typing[/quote]

Sorry about that. you did look like you had the matter well and truly by the cobblers.

BTW, I've ordered that 80amp SSR for the dump circuit. Think I'll put a hefty heat sink on it too - don't trust chinee fella.

Think I would reccommend a SSR and a cuppla hefty diodes for this setup also.

Also don't think I would persevere with batteries that have been that dead for that long.

d.m.

David M.

Jaffasoft

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Joined: 03/11/2010
Location: Australia
Posts: 102

Posted: 01:22am 13 Dec 2012

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If you look at the bigger version (where you can see more of the upper part of the image) in the link of the same image as above, it shows a 12v wind turbine connection illustration. My wires coming out of the two smaller bolts going to the top are back the front! It has the same illustration in the instruction leaflet that was sent out. My controller is wired back the front to that. Its the two tiny looking black and red wires running up to and screwing in the top of the circuit!

Have we ruled this out as not being the problem? Edited by Jaffasoft 2012-12-14

Downwind

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Posted: 02:04am 13 Dec 2012

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Due to power price increases in this country and cut back of spending, one can only guess, its past lights out in the nursing homes, and many members are off line.

So i will answer again......................

A relay is a uni directional device (can work either way ) with 2 parts, a coil and a set of contacts. the smaller bolts are the coil, the larger bolts are the contacts in your case.

So as long you have the smaller bolts (coil) connected to where one or the other is shown on the drawing, regardless which smaller bolt goes to which wire (its unidirectional) it will work.

The contacts are also uni directional, its just 2 surfaces that press together to close the switch, it makes no difference what wire end goes to which of the 2 larger bolts.

How a relay works is the coil (smaller bolts) creates a magnetic field that pulls the switch contacts together (larger bolts).
This allows a small amount of energy to switch a much greater amount of current, while isolating the controls from the contactor voltage.

[quote] Have we ruled this out as not being the problem? [/quote]

Yes we have.
Take a hammer and beat that idea to death.

Pete.
Edited by Downwind 2012-12-14

Sometimes it just works

anteror
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Joined: 06/10/2009
Location: Finland
Posts: 189

Posted: 07:20am 13 Dec 2012

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In my system I have this;

http://ghurd.info/dc.html

This Ghurd unit controls the connect to the dump load, with this
Power mosfet unit 220Amp;

http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL _LITERATURE/DATASHEET/CD00002654.pdf

It connects without any relay tips !

The most critical part connecting big DC loads are the relay tips.

I have made my own dump load from a quality resistance wire, which
you can find from pottery kilns and enthusiasts sites.

It is made in a stone based structure and like this;

http://www.google.fi/imgres?hl=fi&sa=X&tbo=d&biw=1440&bih=74 8&tbm=isch&tbnid=1sBTqgJd-Bh-LM:&imgrefurl=http://www.drsola r.es/eng/products_wind_turbines.html&docid=QqgfrhjkZ1wjvM&im gurl=http://www.drsolar.es/images/Dr%252520Solar%252520dump% 252520load.JPG&w=502&h=404&ei=miXKUIUphvHhBMe2gfgF&zoom=1&ia ct=hc&vpx=4&vpy=425&dur=1494&hovh=201&hovw=250&tx=110&ty=113 &sig=111797391652780640031&page=1&tbnh=144&tbnw=168&start=0& ndsp=26&ved=1t:429,r:12,s:0,i:117

Antero
Edited by anteror 2012-12-14

xoke
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Joined: 03/02/2010
Location: Portugal
Posts: 1

Posted: 01:23am 15 Dec 2012

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Hi guys,

First time this forum

I also have one GHurd controller, and works fine, I have 15 wire resistors connected in paralel (about 1300 watts total)12v system, dump at 14,4volt,

each resistor has one power mosfet IRFZ44N,

I have posted a recent upload to this controller at

http://www.fieldlines.com/index.php/topic,144513.52.html

Regards

Pedro

Jaffasoft

Senior Member

Joined: 03/11/2010
Location: Australia
Posts: 102

Posted: 02:22am 15 Dec 2012

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pThat's good to hear! Nice resisters build. Interesting these ways to make your own cheaper ways. Wish i didn't spend so much money now, think I would have been happier with fence wire

.

My mate is looking to buy a cheap dump load on a hack system on a shoestring budget. One of you(s) enthusiasts interested in tinckering around in your spare time might want to make one and post it on for a little pocket money project... just a possible viable suggestion out to anyone inclined. I will run it by him! Do you connect it to a Solenoid also?

Well, I'm poised here with six more 12 volt batteries connected to the old Telstra ones and having given them a couple hours on the generater charger at a constant 14.8V, waiting so see if the discarded winds for tonight make the "relay chatter".

They are holding at about 12volt charge at the meter now.

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