LED Question

[piesrule]

Hi,
I have always had incans in my display, running off Grinch, Ren-C and SSROZ's.
Next year I would like to change over to LED's. I have approx 40 sets of BigW Led's and I would like to get a lot more (possibly from China) I also have a Ren64 that I have never used.
I would like to get your expert opinions on what sort of setup would be best for me to successfully run a dimmable show with Led's?
Do I need DC power supply, DC SSR's etc. I have very limited electrical knowledge so keeping it as simple as possible would be appreciated. Pictures or drawings would be wonderful.
Thanks in advance.
Terry.

 

[Tabor]

Hello Terry

You have all the gear needed to dim Leds.

For the past two years I have been using a Ren64 with either normal SSROZ's and EZSSR's for some of my Led strings.

All you will need to do is feed the SSR's with a full wave rectified AC signal

It is basically a transformer and a bridge rectifier. I used a 24v toroidal transformer and a large 16A bridge rectifier. All from Jaycar.

If you LEDs are from this year batch of bigW leds you dont even need to worry about resistors.

 

[wjohn]

It is basically a transformer and a bridge rectifier. I used a 24v toroidal transformer and a large 16A bridge rectifier. All from Jaycar.

Lumpy DC ;-) For those wondering why a AC SSR would work on what sounds (and is) A DC Source. TRIACs need a supply voltage that 'returns to Zero' It does not matter if it is full AC or rectified DC. As long as it is not filtered DC, the TRIAC will get a waveform that peaks to around 32 V and falls to 0 V, with a frequency of 100 Hz. All from a 24 VAC Transformer...

 

[Goldie]

Hi Terry

My whole show is using LED and Ren64's, I had the Grinches hooked up last year, but I got a lot of flickering problems with the Ren-c Grinch hookup, so I changed to all Ren64, have not had a problem this year, I'll post a picture of my rectifier, it's really simple to make, I have don't know a lot about electrics either but this worked well for me

 

[Goldie]

Hey

Took some photo's there are four items to complete the Rectifier
2 - two pin PCB connectors
1 - 6 pin IC Socket
1 - Rectifier
1 - bread board cut to 20 hole x 4 holes

Solder the 2 two pin connectors to either end of the bread board
Place the 6 pin IC socket half way down the bread board and solder to the bread board the extreme pins should be in line with the 2 pin connectors (see photo)
cut the tracks of the bread board between the IC socket (see photo)
Mount the rectifier onto the IC socket.
The whole lot can then be placed into a small plastic container, with holes for the wire in and out

 

[David_AVD]

Good idea Goldie.

My only comment would be not to use an IC socket, as they can cause problems long term when drawing higher currents. I have seen the contacts burn when they develop a small amount of resistance due to corrosion.

 

[piesrule]

Thanks guys. Very useful information.
Goldie - Couple of questions. What size rectifier do you use? Does this go between the 24vAC power supply and the SSROZ?
Do I need to build one for every channel?
Lastly, could you post a picture-drawing of everything set up (Ren64, power supply, rectifier, SSR and lights)
Cheers, Terry

 

[Goldie]

Hi Terry

The attached pic's is how I set up my show, I have one Bridge rectifier for each 4 channel SSR, one 24V Toroidal feeds all the Bridge rectifiers (not sure how many this can run but seems to handle 48 SSR's), I don't know how many channels the rectifier can handle (some one else might be able to help here). One lead from the rectifier is then fed to the SSR and the other to the lights, the SSR is then connected to the lights.

Hope this helps, I'll send you two type for rectifiers one with and one without a resistor, this should help you.
If you are going LED I really do urge you to water proof the LED's, they will rust and after about one or two years the connecting wires will rust and break, normally they break as you fold them out or as you put them up Murphy's law

Good luck

Tony