Help! Fade Problems

[Harbs]

I was setting up a new 16 channel board and when testing it I found that when I do a fade

with just one channel set several others also fade or flicker

This is in the hardware test mode. Using the latest LOR software.

This bosrd came already soldered. Seems to do it on both sides of the board.

Does anyone have any ideas



Harbs

[iresq]

Are you using LEDs?

[Harbs]

YES, I am using LED's

Thanks,

Harbs

[Harbs]

I think the problem is with the LED's

I was uing the LED's that CDI sold me . I just read a thread

on the same issue and they said the CDI LED's were the problem.

I will check the board with other lights tommorrow. Man!! I am thankful I did not

buy many of those wacky LED's from CDI. I am afraid Paul will hear alot of complaints

in the next dew days when people start up their displays. Not his fault, but most people will

still voice their opinions.. I will have to readjust my display so I did not use the problem LED's.

I really feel bad for those you are stuck using them.

Harbs

[Richard Hamilton]

Harbs wrote:

YES, I am using LED's

Thanks,

Harbs

That is definitely your problem. You will need a "Snubber on the channels that have trouble.

[-klb-]

Richard Hamilton wrote:

Harbs wrote:

YES, I am using LED's

Thanks,

Harbs

That is definitely your problem. You will need a "Snubber on the channels that have trouble.

I don't think adding resistive load will fix the problems with this year's CDI LED's... Even if it did fix the impact to the controllers and other channels, it won't fix the fact that phase angle dimming will rapidly kill the LED strands..

Adding some resistive load is mostly a benefit for LED's ,where you have a large number of strings on the channel, or really long cords, and the parasitic capacitance of all the cord starts to mess up the controller. But the parasitic cord capacitance is tiny compared to the deliberate capacitance in the voltage doubler in this year's CDI LEDs.

[Richard Hamilton]

-klb- wrote:

Adding some resistive load is mostly a benefit for LED's ,where you have a large number of strings on the channel, or really long cords, and the parasitic capacitance of all the cord starts to mess up the controller. But the parasitic cord capacitance is tiny compared to the deliberate capacitance in the voltage doubler in this year's CDI LEDs.

You would probably know better about issues with CDI LEDs since I don't have any. I hear they are having big problems though. However, as for the comment about resistive loads being mostly a benefi for large number of leds strings on a channel, that is incorrect. Even if you have one string will a problem, a snubber will correct the issue.

[grandlakedad]

Check out this web page.

http://www.crazylightlady.us/TerminatorsHow-To.html

[Richard Hamilton]

grandlakedad wrote:

Check out this web page.

http://www.crazylightlady.us/TerminatorsHow-To.html

I've said it before and I'll say it again... this is one of the most time consuming and dangerous ways to create a snubber. Look around this forum. There are other good alternatives.

[Harbs]

Mr. Hamilton:

I tried making a snubber using your instructions.

However, when I plug it in to the end of the string, it pops and smoke appears.

I used the resistor size as you stated. I think the problem is possilbly the fact that

my plug end is not polarized but the clam shell is polarized. What do you do to get around the polarized plug.

THANKS,

HARBS

[Dennis Cherry]

Harbs wrote:

Mr. Hamilton:

I tried making a snubber using your instructions.

However, when I plug it in to the end of the string, it pops and smoke appears.

I used the resistor size as you stated. I think the problem is possilbly the fact that

my plug end is not polarized but the clam shell is polarized. What do you do to get around the polarized plug.

THANKS,

HARBS

I do not know what resistor you used for the snubber, but the best values are a 33K (33,000 Ohm) 2 watt or a 47k (47,000 Ohm) 1 watt. anything smaller in wattage or resistance could give you your problem.

I am using 47K 1 watt with know problems, LED's are working fine, love the fades and multiple intensities.

Polarity is not an issue using resistors.

[Richard Hamilton]

Harbs wrote:

Mr. Hamilton:

I tried making a snubber using your instructions.
However, when I plug it in to the end of the string, it pops and smoke appears.
I used the resistor size as you stated. I think the problem is possilbly the fact that my plug end is not polarized but the clam shell is polarized. What do you do to get around the polarized plug.
THANKS,
HARBS

If it popped the I highly suspect that the value of the resistor is incorrect and was too small. Perhaps you got a 33 Ohm instead of 33K ???

No resistor should pop immediately even if it is a very small wattage. No, it did not pop because of a polarity issue. Resistors are polarized. In my case where I used the clamshell... mine were not polarized. If you got some that are, you could snip off or grind down the sides of the wider spade to be roughly the size of the smaller one.

[redsea300]

I got some clam shell type like in you post. I built 20 of them and put them on my mini trees. I left one without a snubber, The ones I did worked great on fades and the one i did not was still flickering during fades. This is a great fix and easy to do. I orderd another 120 resistors from Radio Shack. Home depot is 1.97 ec for the plug ends here on the penninsula(S.F. Bay Area)

[Richard Hamilton]

redsea300 wrote:

I got some clam shell type like in you post. I built 20 of them and put them on my mini trees. I left one without a snubber, The ones I did worked great on fades and the one i did not was still flickering during fades. This is a great fix and easy to do. I orderd another 120 resistors from Radio Shack. Home depot is 1.97 ec for the plug ends here on the penninsula(S.F. Bay Area)

Glad you have had good success redsea.

I read my above post again and noticed a typo. I meant to say "Resistors are NOT" polarize", so having a reverse polarity is NOT the reason it would pop. When a resistor pops almost as soon as power is first applied, it usually means you got a very low value (wrong value) or the resistor is defective (I doubt that).

[Harbs]

Thanks for your reply.

I am using 50 count LED. Single string in each channel. (mega tree).

Any Idea what size resistor I need.

I have 2 strings of the alleged CDI problem LEDS in my complete setup

of 120 channels. The remainder are last years LED's which worked great in 2007.

I now noticed nearly all fades are herky jerky.

If I am using the 2 strings of the CDI LEDs will they affect the other lights on other controllers.

Harbs

[redsea300]

You need to use 33k ohm 1/2 watt resistors for snubbers. I did and they fixed all the herky jecky(ha ha) fades

[Harbs]

Thanks for your info.

I did use 33 ohm 1/2 watt 5% tolerance Radio Shack brand.

I tried two snubbers using the clam sheel male plug. Plugged it in at the end of the light string.

It popped and smoked. I have a polarized male plug with non polarized female

plug on the string, I sort of forced the plug into the female side and that may be where the problem lies.

Thanks

Harbs

[cmoore60]

Harbs wrote:

I did use 33 ohm 1/2 watt 5% tolerance Radio Shack brand.

Redsea stated at 33K or 33,000 ohms.

Harbs,

The resistor you used was basically a dead short in comparison to the value you needed.

Chuck

[redsea300]

You said you used a 33 ohm. It should be 33K Ohm(33,000 ohm) If you used a 33 ohm that is why it smoked

[Harbs]

OK MY BAD!! I checked and it was 33 OHM.

I will try 33K OHMs if Radio Shack has them.

Thanks,

Harbs

[Richard Hamilton]

Harbs wrote:

Thanks for your reply.
I am using 50 count LED. Single string in each channel. (mega tree).
Any Idea what size resistor I need.
I have 2 strings of the alleged CDI problem LEDS in my complete setup
of 120 channels. The remainder are last years LED's which worked great in 2007.
I now noticed nearly all fades are herky jerky.
If I am using the 2 strings of the CDI LEDs will they affect the other lights on other controllers.

Harbs

Harbs, your LEDs do NOT determine the size of the resistor. It makes no difference what LEDs you use, the resistor is independent of that.

I use a 33K Ohm resistor. Some other people use higher values up to 47K. The reason that this range is optimal is that if you go lower than 33K, then you will need a resistor that can dissipate more than 1/2 Watt of heat. If you go higher than about 40K or 50K then you may be putting so little load on the channel triac that it won't see the resistor load and won't solve the flicker problem. The idea of the resistor is to put a small constant load on the triacs so they will ramp the output voltage properly.

I doubt that you will see any LED of one brand to interfere with another.

[Richard Hamilton]

Harbs wrote:

OK MY BAD!! I checked and it was 33 OHM.
I will try 33K OHMs if Radio Shack has them.
Thanks,

Harbs

uh huh, thought so ;-)
Thanks for the update.