Author Topic: controlling more than 60amps (Read 4785 times)

Propwash · « **on:** January 31, 2006, 11:09:32 PM »

I am charge controller shopping and don't see any controllers rated for more than 60amps. What controllers are being used on the larger mills. Is it just a matter of using two or more controllers? Is the Morningstar a better controller than the Xantrex? Thanks

Kevin

cdog · « **Reply #1 on:** January 31, 2006, 04:52:44 PM »

I'll be holding my breath for a response to this as I have looked most everywhere myself for something to handle 80 plus amps!!

Cdog.

Propwash · « **Reply #2 on:** January 31, 2006, 05:27:36 PM »

I have not been using a controller, but running loads to hold things down. I have been cooking batteries like hot dogs on a grill so figured I had better get with the program. I have adjusted my mill so that it furls at a 100amps but that still would require two 60 amp controllers to be on the safe side. I hope there is a less expensive solution than that.

Kevin

DingBat · « **Reply #3 on:** January 31, 2006, 06:33:54 PM »

I don't have a controller / etc to try this with, but it might be possible.

Hook a few large relays in parallel with your dump load so their coils are active when current is being routed through the dump load. Then have a few more dump loads seperatly fused and wired to the battery through the relays normally open contacts.

You would also likely need resistors in series with the relay coils to keep them from getting fried. You'd also want sealed relays, or some other arrangement to keep relay contact arcing away from explosive / corrosive battery gasses.

I think the specifics would be determined by the relays chosen and battery voltage.

DingBat · « **Reply #4 on:** January 31, 2006, 07:14:17 PM »

This came out kinda blurry, but it's the best I could do.

Hopefully this will make my previous comment a bit clearer.

willib · « **Reply #5 on:** January 31, 2006, 07:14:37 PM »

cool video propwash ,

your RPM gage looks like it might be a little off.

spinning slowly , to hauling ass was only 50 rpm, as best i could see..?

Propwash · « **Reply #6 on:** January 31, 2006, 08:17:47 PM »

On that tach a 1000rpm reading equals 200 on the mill. 1500 on the guage equals 300 on the mill and so on. The tach has a few settings on it to play with but that was as close as I could get it to being usable. Since filming that I have got my amps output to double at those rpm readings by replaceing some wire that was to small for the job.

Kevin

Propwash · « **Reply #7 on:** January 31, 2006, 09:01:44 PM »

Thank you Dingbat for the great explanation. It looks like with your setup, the controller is operating a relay which operates a dump load that could be of any size. That makes good sense. I have been reading the Xantrex literature but still don't quite understand the 3 functions of the controller and why you can only use one of them at a time. If I understand them correctly, if you are in load diversion mode you don,t get the charge feathering capabilities that are required to get your battery bank fully charged and in a healthy state. You draw some nice pictures for a Dingbat!! There must be a story behind that handle. Thanks

Kevin

harrie · « **Reply #8 on:** January 31, 2006, 09:14:07 PM »

Hi propwash. I have a morning star 60 amp controller, with a series of 12 volt lights for a dump load. My 12 foot duel rotor in the 12- 2x1/2 disk magnets on each rotor, with nine coils 2 in hand #15 mag. wire, has no trouble seeing over 100 amps in 35 to 40 miles per hour winds. having limited knowage in electronics, I too have been wondering what will happen to the controller, but so far it has worked fine. The relay posting, makes sence to me. If anyone else out there can repley to this, with other ideas, I sure would like to hear from you, I dont want to smoke my controller.

great fun. harrie

DanB · « **Reply #9 on:** January 31, 2006, 09:25:53 PM »

Most pulse width modulated controllers turn the heaters on and off at very high frequency. I dont think the relays could respond fast enough - and if they could... they wouldn't last long. Actually - Im fairly sure that relays would not work with a morning star, or Trace C series etc...

I think you might have to bite the bullet and buy two controllers. 12 V isnt the cheap way to go when you start getting serious power in.

ghurd · « **Reply #10 on:** January 31, 2006, 09:30:17 PM »

A reversed protection diode in parallel with the coil could be a good idea, if it is not included internally. The collaping magnetic field will make quite a large voltage, and the controller may not like that.

G-

ghurd · « **Reply #11 on:** January 31, 2006, 09:47:15 PM »

I have been thinking about a simple homebrew like Ed's.

But 3 stages, each turning on a time delay at off relay, the relay controlling the power.

Not exactally designed yet, but it seems easy enough.

Ed's story that I refered to,

http://www.fieldlines.com/story/2005/11/10/2341/9847

G-

SamoaPower · « **Reply #12 on:** January 31, 2006, 10:10:42 PM »

The Trace/Xantrex C series controllers and, I suspect other PWM types, control the power to the diversion load smoothly. In other words, only as much current as necessary is diverted to maintain the battery voltage at the point the charge algorithm calls for. The charge profile for the series connection and the diversion connection is identical.

As DanB points out, the relay scheme is not a good idea. It would confuse the controller and I would guess it would be clacking off and on often.

I believe the C Series can actually handle more current than their rating because the over-current trip-out point is actually 85 amps according to their manual. The lower continuous rating is probably an issue with their heat sink temperature, which could be relieved with a small fan on the heat sink. Try this at your own risk. A pair of these may do it for you in diversion mode.

I don't suggest lights as a diversion load. Their cold resistance is much lower than the hot resistance and could lead to overload of the controller. Battery cooking with your source current capability is a real possibility.

I don't believe any of the current crop of controllers charge batteries correctly but some control is better than nothing.

willib · « **Reply #13 on:** January 31, 2006, 11:04:55 PM »

Sorry didnt mean to be critical at all..i was just making an observation...

Those amp readings were VERY Impressive..

ffoegw · « **Reply #14 on:** February 01, 2006, 01:18:27 AM »

I also am trying to find a way to control larger generator outputs with off the shelf or some build it yourself plan.

Having not found anything I will describe an untested alternative which might work:

Fluid Power or hydraulics.

: Use a windmill to drive a hydraulic pump.
: the hydraulic pump continually pressurises a large hydraulic accumulator.

(this is a mechanical/fluid version of power storage something like a battery)

: Have several outputs from the accumulator to valves which only turn on after a certain pressure is reached or surpassed and output only that pressure. There is a name for them but I forget what it is.
: Have the low pressure valve turn a variable speed hydraulic motor which can now be perfectly matched to any off the shelf ac generator providing the correct RPM consistently and therefore absolutely clean 117ac 60hz.
: Also have an output to a much higher rated pressure valve which now turns on a greater HP Hydraulic motor which in turn drives a much larger generator providing 117ac 60hz with the wattage of the larger generator.
: and so on and so on until you think the expense is either too great, the windmill cannot provide the power or the village/town/city/megapolis you are selling power to can't buy anymore.
: Have a hydraulic fluid reservoir which receives the extra fluid should the hydraulic pump provide pressure which exceeds the safety rating of the accumulator.
: Have the input to the hydraulic pump and the outflow from the hydraulic motors go to the same reservoir.

Please let me know if you get this working.

Regards

Geoff

Flux · « **Reply #15 on:** February 01, 2006, 03:03:14 AM »

I would also warn against using relays with pwm charge controllers.

A simple on off control will work with relays. If you want to keep it simple just use Hugh's circuit and you can use the relays as pilots to switch larger relays or contactors and go as big as you want.

Not sure if it is on his website or only in the windmill plans.

Flux

nothing to lose · « **Reply #16 on:** February 01, 2006, 04:34:15 AM »

Hey guys I got to warn you, I had a thought.

I have not tested this in anyway.

I think it should work the same for any volts. If we had a relay to turn on and off at our desired max charge voltages and used this relay to trigger a ford type starter solenoid I think we could have some pretty high dump loads.

How many amps is a starter drawing when cranking a 460ci engine? OR when I had a timming gear bust and ran the van with a standard transmision in 1st gear on the starter. Those solenoids seem to handle alot of amps well, and they are cheap enough new or nearly free from a wrecking yard.

So if we turn a relay on and off from the battery bank, run 12V through the relay when on to the one small post of the solenoid we trigger it on and off with the relay. Ground the solenoid and run a positive to one post from the battery bank and the dump load to the other post. Relay turns on, solenoid triggers on, dumpload is on.

I thought I might try this on a 48V bank, I think the solenoid will pass the higher volts ok, but I have to trigger it with 12V somehow, perhaps a tap off one battery ran through the relay?

drdongle · « **Reply #17 on:** February 01, 2006, 05:25:05 AM »

Starter relays are only rated for intermittent duty. You will need relays rated for continuous duty, other wise magic smoke!

wpowokal · « **Reply #18 on:** February 01, 2006, 06:16:38 AM »

Just a simple moderating view, you most probally do not need to dump (however) all incomming load. Your batteries can absorbe a contiuious current relative to their amp hour rating.

allan down under

electronbaby · « **Reply #19 on:** February 01, 2006, 06:53:47 AM »

I would stay away from using a PWM charge controller or PWM diversion load controller for triggering dump relays. The idea sounds good at first, but PWM is tricky stuff. There is a reason why the companies that manufacture this stuff only suggest resistive loads. Dan is right, they dont care about frequency. If you were to place a volt meter across the PWM output while it was active, you are more likely to see half the operating voltage with a RMS meter. It makes even more sense why it wont work when viewed with a scope. And duty cycle comes into play. What you need is a pure DC output.

I dont think Xantrex makes one, BUT Morningstar makes a plug in logic module that allows 4 external relays to be controlled by voltage programmable setpoints inside the controller. This will allow you to do what you want. You could even program 8 different high and low threshold points that will turn on and off 4 different relays for adding and subtracting seperate dump elements. I think it sells for $100 and is called the morningstar "RelayDriver". do a search for it on their site.

You can use these as primary relays to drive any size bigger relay to control your dump loads.

I have a SWPlus 4024 running my house. I use the Xantrex/ Trace ALM module. It allows you to program voltage setpoints inside the inverter and it will control the ALM, which is nothing more than 3 external primary relays. One is even temperature compensated so you dont dump at too low a voltage when its cold out. It seems to work well, and I think DanB does it the same way. I just dont like the fact of relying on the inverter to control the turbines. If there ever was a failure, or an error state, it might not function.

I have recently picked up a Pentametric by bogart engineering (a little pricy). This box allows me to monitor the whole system as far as battery capacity and also has an external relay that is programmable through the firmware. After the voltage was carefully aligned with the other units, it is programmed with the same voltage points as the inverter and the relay closure is tied in parallel with the ALM. I now have a redundant system and i feel a little better LOL.

If you have a Morning star controller, you should really look into the RelayDriver. It might work out well. :-)

Have fun!!

RoyR

KB2UHF

DingBat · « **Reply #20 on:** February 01, 2006, 08:15:40 AM »

Good find, I wasn't previously aware of the RelayDriver product.

Here is a link to RelayDriver on MorningStar's website.

ffoegw · « **Reply #21 on:** February 01, 2006, 08:17:09 AM »

: Have several outputs from the accumulator to valves which only turn on after a certain pressure is reached or surpassed and output only that pressure. There is a name for them but I forget what it is.

A sequence valve combined with a pressure regulator or reducing valve:

brief description of valves found in the following link:

http://www.patchn.com/fluidsymbols.htm

regards

Geoff

ffoegw · « **Reply #22 on:** February 01, 2006, 08:36:03 AM »

": Have a hydraulic fluid reservoir which receives the extra fluid should the hydraulic pump provide pressure which exceeds the safety rating of the accumulator."

Instead of dumping excess electrical power the fluid being pumped into the hydraulic accumulator which casues an over pressure condition simply squirts out into the fluid reservior.

Recommend the volume of this fluid be measured as it represent the potential to either add another generator or increase the capacity of or add another accumulator.

finnsawyer · « **Reply #23 on:** February 01, 2006, 09:29:25 AM »

Hmm. The solenoid on my Johm deere 350 crawler is rated 300 to 350 amps starting. It is repairable in that the contact parts can be replaced. I've had the thing apart. It's easy to work on. The movable contact is a copper disk about an inch in diameter. The fixed contact is a heavy triangular shaped piece of copper. If the coils don't burn out, it is conceivable that the contacts could handle 60 amps on a continuous basis. It might be worth a try.

coldspot · « **Reply #24 on:** February 01, 2006, 12:48:11 PM »

My charge controller has expandable for High amperage.

"FlexCharge" "NC25A-12"

page 20 of manual shows 60A,75A, 100A or multiple.

"www.flexcharge.com"

just my $0.02

Propwash · « **Reply #25 on:** February 01, 2006, 02:24:38 PM »

Wow, it never ceases to amaze me what a cry for help on a good board can do. Thanks to all for the help. Willib I took no offense to your post whatsoever. I have to get some fresh video up for your viewing pleasure.

This is how I am understanding my options for dealing with excess amps. One is to put the amps through a controller in which the pwm pulses the amps out to a source which in most cases is a heating element. A relay cannot be connected to a pwm. In this case you are limited to 60amps of current. I did read in the Xantrex information that a c60 will handle up to 80amps for a period of 10 minutes and then the controller will shut down. So the only way to increase amp capacity is to add a second controller.(I have not read up on the controller mentioned that has add on capacity but I will)

The second option is to use a simple switching device that switches on a relay which in turn enables a dump load. It seems like since this method does not use pwm technology that my battery bank won't get that tender loving and gentle like charge that it so muchly deserves to stay strong and perky.

And then can it be true that the best of both worlds are available by using the Morningstar controller with the add on relay driver? I am most excited by this and will be off to study thier site and information.

I just purchased a bank of C and D kcr15 2volt batteries. I got six of them and a 50watt VLX solar panel for 200 bucks. I got them connected to my system late yesterday. I ran my mill for a short time today while home for lunch and noticed that I didn't get the bobbling voltage readings that I did with the bank of golf cart batteries. A heavy wind gust would only make my voltage go up less than a volt where as before it would make a two or three volt jump on the guage. I don't dare run the mill unless I have my eyes glued to the volt guage. I am most anxious to get a controller on so that I can let her be happy and spinning. Thanks a bunch guys. I off to further my studies.

Kevin

Frank06 · « **Reply #26 on:** February 01, 2006, 03:59:43 PM »

A couple of casual observations...

FWIW, NEC requires redundant controllers when using diversion as a charge control method. I guess they don't think that overcharging is such a great idea either... given the cost of batteries you could buy a proper control for the same money I would think. I would check EvilBay to see what's kicking around. Don't forget that a lot of hydrogen gas is given off at high voltages too which can be an issue. Another source might be local PV dealers who might have used units kicking around.

We use a Morningstar TS60 to run excess PV output through a DC water heating element. They're expensive (~$75 or so) but save money for domestic hot water. I also use a Crydom relay driven by an Outback MX60 (PV) charge controller to gain additional diversion capacity. The advantage of PWM control is that it can control to a very fine degree what voltage to divert at. The MX60 can switch at tens-of-hertz (at least) which works to control excess current pretty well. I'm not familiar with the Trace/Xantrex controllers but the TS60 has various "programs" you can select; if I remember correctly they reduce charge voltage after some period of time so you don't hold your batteries at higher voltages for too long a time. You are also supposed to be able to communicate via a RS-232 port but I couldn't get that to work on my controller. This would allow you to custom program setpoints, etc.

Someday when my wind machine is working ("fingers crossed") I plan to add diversion capacity via additional relays in parallel as the MX60 can divert full-time even if there's no PV input i.e. it is supposed to work at night. I'd be interested in learning about less expensive solutions but don't think that mechanical units would hold up.

Thanks for the link to the Morningstar relay driver - new to me.

And sorry for the long post.

Propwash · « **Reply #27 on:** February 01, 2006, 04:02:37 PM »

This is the owners manaul for the Morningstar charge controller. See page 42 section 6.0 for its charge diversion functions.

http://www.morningstarcorp.com/products/TriStar/info/TS_Manual.pdf

Frank06 · « **Reply #28 on:** February 01, 2006, 04:09:17 PM »

Here's a link to a larger solid-state relay that might be of interest:

http://www.hellroaring.com/industr.php

Propwash · « **Reply #29 on:** February 01, 2006, 05:32:13 PM »

Hi Coldspot,

Do you have any idea what the price range is on the Flexcharge unit? They don't show any prices on thier website. Seems like a nice simple unit. How long have you been using your controller?

Kevin

Propwash · « **Reply #30 on:** February 01, 2006, 05:58:21 PM »

Hi Frank06,

That Morningstar TS60 looks like a real honey. I noticed all the units are shown with the optional digital readout already attatched to the controller but they cost another 95 bucks to purchase. Do you have the optional digital readout and do you feel it is needed? I'm a little dissapointed to hear that you couldn't tie into the unit through the data port. Do you think it was just a computer glitch on your end or a problem with the controller. It looks like if you buy the controller, digital readout and relay driver it puts you up to the price of the Outback which I here is the Cadillac of controllers. Thanks

Kevin

cdog · « **Reply #31 on:** February 01, 2006, 06:09:47 PM »

Propwash, there is an entry on the board I found that is about a year old. He has a very nice looking setup and the type of control he used was a pulse 60 amp. He goes on to say that he talked to the tech at pulse and claims it can handle 3 times the rating. If you google search "pulse 60" it should be the first to come up.

Does anyone have a link to their home site? Cant seem to find one, Thanks,

Cdog.

Nando · « **Reply #32 on:** February 01, 2006, 06:14:57 PM »

Kevin:

For the time being, it is best to set your mill to Furl at 60 amps if it is possible.

If you are going to connect two controllers to attain 100 + amps, I would suggest that you do a offset setting.

Set the bulk charging of the early dropping controller to drop about 0.1 volts lower than the second, this way no hunting will occur and both will operate smoothly.

You will need a good ballast controller that indeed should be a PWM controller even though one of the messages by "electronbaby" says something against it -- to control resistive loads which is the natural way to dump the excess energy from the mill ( of course one can direct such power to heaters, for water or what ever ).

You indeed have a basic problem --- 12 volts --- with high power, 100 amps is to much to work with with low volts.

Even 24 volts is too low voltage but the current can be handled a bit easier -- preferable 48 volts -- that starts to "give" problems around 3 KW.

The relay driver may OK for a load that is energized few time a day, for power sources that may be energized many times a day, like 100 to 1000 times/day, I would not suggest such arrangement -- the relay will last few months, high current relays may have 50 to 100,000 cycles, this is a short time indeed.

With a PLC - Programmable Logic controller with the addition of several MosFets one can have a 100 + amps charger controller and as well the ballast controller all in one package.

The PLC project may require additional items, like current detector, voltage detector and the capability of having the charge controller with MPPT capabilities to harvest additional power from the mill.

Also, with the PLC, one has a PWM controller to attain better charging capabilities with true MPPT profile.

This PLC needs to have high frequency PWM capabilities -- they are available.

Learning to program it is a process that may take time for some.

Nando

News:

Author Topic: controlling more than 60amps (Read 4785 times)