redrok tracker

[Rabrsniver]

I finally got around to hooking up my Redrock circuit board to my Superjack ZARL 3018 satellite dish actuator for my solar array tracker.

It hasn't gone through a full cycle yet, but I've noticed something that I don't think is right.

When it is in full east position, the motor still runs every minute or so, even though it can't go any farther east. Is this normal, or is there a problem with the limit switch? Doesn't seem right - it will be cycling all night wearing down the battery, right?

If the limit switch is the problem, is there a way to adjust it?

It has just starting going west. I guess I'll find out later if there is the same problem at the other (west) limit.

John

[TomW]

John;

Adjust your limit switch.

That is almost certainly the problem.

Usually it is on the end of the shaft that drives the arm under the cover.  Some pl;astic bits with a cam and follower that rotates.

Do not know that actuator so "how" might be different.

Google up the actuator you might find some info.

Good Luck with it.

Tom

[David HK]

Check your limit switches on the actuator to ascertain if they are NO (Normally Open) or NC (Normally Closed) types.

I had a similar problem and had to change my actuator limit switches for a type that incorporated electrical contacts for NO and NC so that was very convenient.

Its so long since i made the changes that I forget what my switches are - NO or NC, but it definitely solved my problem.

Hope this helps.

David in HK

[Rabrsniver]

Got the limit switches adjusted - now different problems.

The tracker goes west, but doesn't return east. It did  go east if I completely covered the LEDs, but it didn't do it by itself overnight or early in the morning. Also, the speed of the west movement is WAY too fast.

I've read some on Redrok's site, but he is way above my level of knowledge, and he assumes everyone knows what he's talking about.

There is mention of being able to adjust the cycle time and duration, but the only thing I see that can be adjusted is the potentiometer.

Will this make the cycle slower? Right now it goes on about once a minute. He says it can be slowed to once every 5 minutes. I think that's still too fast, but ....

John

[Volvo farmer]

I think you still need to adjust your limit switches.  The tracker needs to sense the west limit has been reached before it will attempt to park east after dark.

Look about 1/5 down Duane's ginormous web page, and you will see a little explanation of how limit switches work.
http://www.redrok.com/electron.htm

I have adjusted that potentiometer before. I believe it adjusts the duration that the motor is energized, not the interval in which it it energized.  I may be wrong about this, but having watched my own trackers, I believe that once the thing gets centered on the sun, it might go several minutes without energizing the motor.

What voltage are you driving that linear actuator with? I believe they are designed for 36V but if you drive them with 12V, they actually move quite slowly.

[David HK]

Can you provide more information.

Which model of Redrok tracker are you using? Let us know so that readers can refer to it on the redrok web site.

I am not sure its a limit switch problem anymore. When you write that it will not park in the East are you trying this as a test in daylight or real time as darkness occurs? If its the latter then it should logically mean that a variable resistor needs adjustment.

Volvo Farmer is quite correct in his observation that many satellite actuators are designed for 36 volt operation and track very slowly when fed with 12 volts DC. This is exactly what happens with my system.

For your information my system operates on 12 volts DC and the electronics are all centered on an LM339 IC.

Keep working on it.


David in HK

[Rabrsniver]

Hi,

I'm using the LED3X24V3c tracker.

The limit switches are adjusted correctly now. It DOES park in the west, but doesn't want to return east in darkness.

I am using a 12V battery to power the tracker. It does move slowly with each cycle, which is fine, but it doesn't "park" at all during the day. It just keeps moving west, (about once a minute) and even if I adjust the potentiometer, (you're right Volvo Farmer) it only changes the run time, and not the time between cycles. Consequently, it goes full West long before it needs to. (Probably only takes an hour from full east to full west)

I thought too that it should "park" during the day when it is facing directly at the sun, but it doesn't. Right now the sun is almost directly overhead during the day - part of the problem? I really don't think so.

Any suggestions?

John

[Volvo farmer]

We need to define some terms here.

"Parking" is movement from west to east, done slowly over a period of 30 minutes to an hour. It is done after the sun goes down and after the west limit has been reached, when there is no sun to track.  "Tracking" is the movement from east to west, following the sun.

If your tracker parks in the west after dark, you need to flip the circuit board upside down, then it will park in the east. The components on the circuit board should point up, or north, depending on your perspective.

If your tracker does not accurately track the sun,  then you might have other problems which are hard to determine without more information.  I would make sure the board is properly mounted,  the linear actuator somewhere in the middle of it's travel, then apply power to the board on a clear sunny day and observe the behavior.

[TomW]

I would add that you should set the actuator limit switches with the tracker out of the circuit.

Just power it directly to set those. This ensures the motor shuts off on its own at the proper physical limits. Full retraction or full extension.

This is very important I think.

Just from using various tracker schemes to drive sat dish mounts over the last decade or so. Including manually with a DPDT knife switch that I do now waiting for a prototype from a member that will hopefully provide an alternative to Duane and his severe lack of support for customers. Duane is another rant so I leave it at that.

But do get those limit switches sorted out first so you do not damage the motor running it against its stop or over extend it and unscrew the drive screw and letting it come apart which could let it flop over and damage the panels.

Tom

[wilfor03]

Yeah, what they all said!! And, after you swap your board 180 degrees, check after dark and make sure you don't have any stray lights shining toward your board (false daylight). That has already happened to me. Let us all know how things work out for ya......Bill

[Rabrsniver]

Hi,

My circuit board IS facing component side up. I will reverse the actuator wires and see if there is any difference.

Yes, you're right. I just used the wrong terminology. It "tracks" during the day much too quickly. I guess by your definition it doesn't "park." Just goes full West and stops there. (Maybe it thinks it is parking instead of tracking.)

I agree about Dwayne. I've emailed a few times with no response. But I did receive the board fairly quickly, although it was purchased over a year ago.

Thanks for all of the advice. I'll keep posting my progress.

John

[Rabrsniver]

I flipped the board over. Now its component side down, which is contrary to what I think it should be.

Anyway, now its started going east (in broad daylight). It continues to advance every minute or so.

Any more suggestions?

Thanks,
John

[Volvo farmer]

I flipped the board over. Now its component side down, which is contrary to what I think it should be.

Anyway, now its started going east (in broad daylight). It continues to advance every minute or so.

Any more suggestions?

Sounds like you had the orientation correct the first time.  If your tracker overshoots the actual position of the sun and keeps on going all the way to the limit, you definitely have a problem. My only guess is that perhaps some building or something light colored is fooling the tracker into not knowing the brightest part of the sky is the sun.  Or perhaps if it sat there for a long time trying to move the locked-up motor before you adjusted the limit, the circuit might have become damaged.

I have had a half dozen or these boards installed and in daily service and I have never experienced what you are describing.  I have had trackers temporarily overpowered by high winds and had them confused by clouds. I have had one blow up a FET and refuse to move the array, and I have had bad connections at the board due to my ham-fisted attempt to bend connector pins, but I have never had one run past the sun ans all the way to the limit.

[chainsaw]

If my memory is correct which is questionable, I had the same symptoms a couple of years ago. I was trying to wire  switch(s) in the circuit to manually control the actuator. In doing so I reversed the polarity (brain malfunction) by having one of the switch(s) wired incorrectly. After removing the switch(s) from the circuit and reconnecting the tracker normally, my array would track to the West but would not return to the East.

Upon removing the circuit and using a magnifying lens I could see damage to a couple of the components aka "magic smoke".

[hydrosun]

It sounds like either the comparitor or one of the led sensors  isn't woriking.  check to see if one of the leds leads is shorted together. That would make it go only one way in daylight. If you didn't damage the circuit by hooking it up backward you should be able to get a replacement from Dwayne. If you can get in touch with him............   
I bought a circuit from redrok recently and it is also tracking strangely. It doesn't want to track accurately in the morning. The owner has used tape to cover the back of the plastic jar to avoid light coming from under the array without success so far.  It is on a system 30 miles away and haven't gotten back to trouble shoot it yet.
Chris

[Rabrsniver]

I finally got it working fairly well. I was able to reach Duane (must have been my lucky day) and he helped a lot. I didn't see it anywhere on his site, but there is a small LED next to the main connector that shows which way the tracker is going. If it lights RED, the tracker is going east. If its GREEN, then its going west. So I removed the circuit from the array and watched the lights.

I had it backwards, so I reversed the wires to the actuator. Last night it parked after going completely west during the day. But I think the circuit itself is not in the best position on the array. The array seems to be ahead of center of the sun during the day. I have it mounted in the northeast corner right now.

I'm going to move it to the center of the array and see if it centers on the sun better.

At least iits working! Thanks to everyone for their comments and suggestions. I will post again and let everyone know if re-positioning the circuit helped.

John

[Volvo farmer]

Before moving the mount, try tilting the circuit board relative to the array. If the array tracks too far to the west, tilt the circuit board more to the west and it should track more accurately.

[hydrosun]

I posted the other day that one redrok tracker was working strangely. The owner put duct tape over the entire jar that the circuit was in. It is now working correctly. I'm guessing that the duct tape is blocking any reflections and dimming the light hitting the sensors. The jar is mounted below the panels and sticks out a few inches from the bottom. It might have been getting some reflection from the bottom edge of the panels when not directly in line with the sun and causing a false reading in the morning.

I'm glad you were able to get yours tracker working, it's always confusing to me when trying to fine tune the position of the circuit because it needs to be rotated opposite to the way you want it to correct.

The small connectors on the board have always been hard to use, especially if you have to change anything.  On this last install I pushed the pins further apart and used  small connectors with set screws. They come in different sizes and in groups of 10. They can be cut to choose how many you need. I find them in one of my local hardware stores and Lowes carries one of the sizes.
Chris

[Rabrsniver]

Still having issues with the tracker. It parks at night fine, but it continues to go west way too far to stay in line with the sun.

I have:

Moved the location of the tracker to 4 different areas of the array, with no improvement. (Northeast, northwest, high middle, and middle)

Covered the glass jar with duct tape - no help

Tried it without the jar cover - no help

I think the problem is the arrangement of my array. There are 4 panels mounted in a square which is open in the middle. But the movement as it goes from east to west kind of "twists", so the orientation of the tracker changes as the array moves throughout the day. Consequently the LEDS aren't always facing east and west.

Some parts of the day it works fine, but its especially bad in the morning. By 11 am the linear actuator has already extended 1/2 way.

I'm getting very discouraged. Any suggestions?

John

[TomW]

Maybe shim one side of it up so it offsets the difference between where it thinks the sun is and where it actually is?

Check the LEDs for uglies, scratches, bird poo, etc.

The older versions you could tweak the LED "alignment" to fine tune it. Maybe one is way off or something.

I won't go into warranty relief because it does not seem to carry anything like a warranty.

Tom

[Basil]

I had a redrock tracker that worked real good.
BUT it took day after day after day adjusting it to get it right.
Once it's adjusted Right it GREAT.

You have to think ( small adjustments at a time ) Look at ever thing.
Look at the sensors and the angle each time you adjust it.
The cover can change everthing on / off. Do all test with the cover on.
The cover could be the problem at a set part of the day.
I think he said use a plastic pennut jar.
I had my sensors looking up through the side not the bottom.
You will get there. It does take days to get it right.
Unless your Lucky.

[David HK]

First of all don't give up.

Can you put up any photographs of your array - it does help problem solving.

An obvious question - is your array aligned due North and South assuming you live in the Northern hemisphere?

Is your array rigid, and does not flex when driven through the arc?

I suspect that your type of circuit is very sensitive to detecting the sun.

On thing I would try and that is to put the sensor in a tin (or other type of container which has solid walls and a bottom) instead of a glass or plastic jar, so that the container 'sides' act as a shroud. The sensors can still point to the sky and see how it reacts. Take precautions to ensure that the circuit sits on suitable insulation so that the PCB does not destroy itself by short circuiting on the metal of the tin or other container. If in doubt, don't do this.

Is it possible for your sensor circuit to 'roll around or move' when it sits in the jar? How is locked firmly into position inside the glass jar?

You report that the mounting 'twists" as it moves through the arc? If so, that is not helpful.

Remember that jars have all sorts of curves and bends including knuckle screw threads, any of this could cause extraneous light transmission to affect the sensors.

David in HK

[Rabrsniver]

Hi David,

First of all, my circuit is firmly mounted in the jar, so that shouldn't be the problem.

I have totally taped the outside of the jar.

I've tried it without the jar.

The array is pretty rigid as it moves.

I have a couple of pictures, showing parked and full west, but I don't know how to post them?

I'll try using a can instead of the jar, but I really don't think that's the problem.

John

[Volvo farmer]

I disagree that you should use a can instead of a jar.  All three of mine are in peanut butter jars.  I found it easier to mount the circuit to the lid of the jar, then just screw the jar over the lid. These boards have a little hole in them. If you can use that hole to mount the board, it's pretty easy to tip it east or west to adjust the center.



I'm curious. If you leave the array alone and look at it at high noon, how far off from the sun is it in degrees?

[David HK]

For clarity I am tossing ideas into the air at the moment in case they prompt a thought or direction in which to try.

Volvo Farmers photograph above does trigger a thought.

Is your sensor board the same or similar as the one shown in the above photograph? If Yes, what material have you use to mount it and then link it to the jar cap? If its metal make sure that the clamping pressure is not causing any momentary short circuit on the PCB tracks. its worth a check.

Do you have a mono spy glass or powerful magnifying glass? If so, spend some time in good light examining the solder side of the PCB to see if any globules of solder are causing a short circuit. Also check all the solder blobs  to try and identify any that may be a dry joint.

Check and check again and keep coming back with reports and we will keep on  thinking.


David in HK

[David HK]

John,

Did you buy this tracker unit already assembled and ready to go, or, was it all in parts which you had to assemble yourself?

I have spent some time perusing the redrok website and if I have been looking at the correct tracker, its quite a sophisticated unit that needs careful assembly, and testing. The setting up instructions are quite detailed.

David in HK

[Rabrsniver]

First of all, I want to thank everyone for their input and suggestions.

In no particular order:

The tracker was purchased already built. (not as a kit)

I have used a small piece of plastic to insulate the board from the mounting piece.

I have pointed the array directly south when the actuator is at the center of its travel, so that when it parks it will be as far east as possible.

By noon, its about 20 degrees ahead of the sun.

I have carefully examined the circuit board, and all soldering appears to be fine. I have used a multimeter to check continuity.

Can anyone explain to me how to post pictures? Maybe if you guys see them it might help.

Thanks,
John

[wooferhound]

How to post Photos . . .
http://fieldlines.com/board/index.php/topic,143664.0.html

[David HK]

John,

On Sunday morning I printed off a copy of the redrok circuit that i believe you have and drew out the circuit plan on PCB Express software.

I came across an interesting problem which was to plot the pin holes for the two large 10 mm sensors. I have now worked out that both sensor LED's are set at 45 degrees to the centre line of the PCB.

Since your circuit came assembled and through the postal service (I assume) then it could have been subject to all sorts of bad handling. My suggestion is that the failure to track the sun more precisely could be due to one or both sensor LED's being out of alignment. You may wish to consider checking this point of detail and check the angles.

This is about as far as I can go with suggestions. I hope to build a copy of the circuit and have it ready in about two weeks. I will let you know how i get on.

David in HK

[hydrosun]

I don't know if this has any bearing on your problem but I've tried putting black electrical tape around the led sensors to only allow light to come into the tip of the led. This seemed to eliminate the light coming in from the sides and reflections. Not all of the circuits have needed this but it might help .
Chris

[ghurd]

I don't know if this has any bearing either.
We did some preliminary testing of LED for use in tracker circuits, which caused me to abandon the idea.
Tested a lot of different LEDs.  Different colors, viewing angles, brightnesses, under different conditions, etc.

Without exception, the aim of the LED was critical.  Far past the point of reasonable.
It could be Chris' tape solved some of the problem.

Might check that each LED set is pointing in exactly the same direction.
G-

[Rabrsniver]

Hi, Ghurd and others.

You're right - the adjustment is VERY fussy. I think I finally have it dialed in. It was a two fold problem, I think.

First, the jar I used (Vlasic pickles) had a kind of fancy bottom outside edge. Swirled flower-looking things. I think it was bouncing weird light at the LEDs. I replaced it with a clear plastic parmesan cheese jar that seems to be just the right size and holds the circuit well.

Second, it was still way ahead of the sun, so I moved it around until it stopped moving when it was centered on the sun. It went through a full cycle today and parked OK.

I'll see if it does well tomorrow from a total east position.

John

[David HK]

Excellent.

Yes, the bumps, decorative work and scrolls found on glass jars could well contribute to the general upsetting of the LED sensors.

Keep us informed about progress.

David in HK