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View Full Version : Power draws for olsen 595 stuff (measured)



jstlucas
01-05-2008, 05:56 PM
Ok, maybe there's other posts about this somewhere, but after Christmas I started measuring the current draw from my olsen 595s and ssrs. After narrowing down what' on, what's off, here's what I got from the +5V supply. The numbers have been rounded but give an idea what to expect.

Each LED on the olsen board draws about 5mA. No big deal unless you're running 192 of them on three boards (plus the power indicator LED if you have one). The rest of the ICs on the board are almost negligible compared to the LED draw.
Each "on" SSR board that I have (4 triacs, optos, etc) takes about 27mA, using the various lengths of wire to them.

So one 64 channel olsen board (64 leds) and 16 ssr boards runs about 0.8A (800mA) at +5V. The 192 channels w. 48 SSRs runs about 2.4A. Eliminating the LEDs would knock the current down but I like having the indication that the channel is working.

Of course the draw from the lights is completely separate.

Joe

Macrosill
01-05-2008, 06:44 PM
Joe,
The 800ma is the same number I listed in the Coop 595 assembly instructions. I actually came up with 390 for the leds and 390 for the optos. I rounded that off to 800. I then suggested a 1 amp supply so a 800ma ps would not be over taxed.

Sean Bowf
01-05-2008, 09:35 PM
Joe, what is the value of the SIPs on your controller board and the opto input resistor in your SSR boards??

Sean

Toaster
01-05-2008, 10:13 PM
I will add, that I was running my olsen 595 (x2) with 128ch of SSR (32) through the +5v on my computer PSU, which was rated at 350watt (30amp on the +5v side according to the label on the PSU)

Anyway, I was getting severe fading or dimming when I was ALL ON. I originally had it pulling +5v from the USB plug and was advised against doing that, so I ran it straight from a Molex inside the computer and a female usb plug..

Anyway: at some point during the season, we had a computer problem, and a neighbor asked if we'd turn the lights back on so her family (from out of town) could see them, so my son moved his computer box down there, and fired them up.

Well, he used his USB port to power the Olsen/SSR plug, and the lights NEVER faded or dimmed - even on ALL ON... And they were considerably brighter. THIS IS NOT MY IMAGINATION. My whole family saw it...

His machine has a much nicer high end 500w power supply (cooler master I think?) the show computer was some generic $30 case + psu from Fry's....

+5v are not all the same. Make sure whatever powers your display has enough juice, otherwise your lights may dim, fade or not power on to there fullest. WE EXPERIENCED THAT THIS YEAR. Next year I'll have a nicer computer running the display, or at least, a better +5v power source.

Creg
01-06-2008, 11:01 AM
I may be hearing you incorrectly, but are you saying that it affected the lights connected to the SSRs? How is that possible. If you are using a 595, there's no dimming so it should either be on or off. I'm still new to this so what am I missing?

Mudsculpter
01-06-2008, 12:24 PM
I may be hearing you incorrectly, but are you saying that it affected the lights connected to the SSRs? How is that possible. If you are using a 595, there's no dimming so it should either be on or off. I'm still new to this so what am I missing?

He must have a Ren-C dimming unit as well.

XmasInGalt
01-06-2008, 12:41 PM
I had the same issue. What I believe he is saying is that the voltage dropped below the required 5volts so the voltage to each opto would decrease with every channel that was turned on until the voltage was too low to power any of the optos (and the ICs on the Olsen). This would make the lights attached to these channels dim as the voltage to the optos decreased.

Sean Bowf
01-06-2008, 03:14 PM
I had the same issue. What I believe he is saying is that the voltage dropped below the required 5volts so the voltage to each opto would decrease with every channel that was turned on until the voltage was too low to power any of the optos (and the ICs on the Olsen). This would make the lights attached to these channels dim as the voltage to the optos decreased.

I dont think the optos work like that. I think they are either on or off... The opto only allows 115 VAC to go through it to the TRIAC...and with a 595, it is a discrete (either there, or not there). Unlike a Renard, which sends small pulses to turn the TRIAC on at different times in the AC cycle.

Dimming is done by turning on the TRIAC later in the AC cycle, so that the TRIAC is not on for the whole cycle. The TRIAC automatically turns off when it hits zero volts (zero cross) and has to be turned back on for the next half cycle of AC.

In this picture...you can see two different reference points in the AC sine wave:

http://home.sw.rr.com/bowf/sinwave.JPG

If the on triggers on a Renard are sent at time A in the waveform, then you get pretty much full brightness of your lights. If it is sent at the B time in the waveform, then the lights are very dim. Of course it can be sent at any time in between for different brightnesses.

After that long ramble...In short, I don't think the amount of current or voltage to the optos will vary the brightness of the lights. The opto should either be on, or off...but weirder things have happened... :D

Also...I would need to go try to digest the data sheet to make sure, but I think the holding current is much lower than what is required to turn the opto on in the first place. In short, it takes more to turn it on than to keep in on.

Sean

EDIT: I just looked out of curiousity. The holding current is 100uA (micro amps) or .0001 amp...as opposed to the 5mA it takes to turn it on or .005 amp.

XmasInGalt
01-06-2008, 06:04 PM
Sean,

Thanks for the info. I reviewed the spec sheet for the opto and it's just like you said. The interesting thing is that I noticed when I turned on channels one by one, the ones that stayed on (some would go off - perhaps less sensitive that the others) would decrease in brightness. Dont' know how it happens. That was when I made the mistake of running the 5V to the Olsen via the cat5 cable. Quickly realized my mistake and powered each Olsen directly. I should of looked at the spec sheet before saying anything. Thanks for keeping me honest.

Sean Bowf
01-06-2008, 07:40 PM
I wonder if that was associated with type of 595 we use (74HC595). It requires a certain percentage of applied voltage as a high (can't remember what it was off the top of my head). There is another 595 that someone (phil?) mentioned earlier (74HCT595), that only requires a certain voltage as a high (2 volts if I am reading the data sheet correctly). Might be a little more susceptable to noise...but if we used one of these as the lead in chip on our controllers, it would probably solve a lot of our problems with the 595. The problem is that I have only seen it for sale in one place, and it required a quantity purchase, I think of 25 chips.

Sean

P. Short
01-06-2008, 08:21 PM
The problem is that the HCT parts are hard to find, and often expensive as a result.

--

Phil

RJ
01-06-2008, 10:04 PM
It is possible he is getting to the point he is not able to trigger as you have said do to voltage drop. Then once it drops and the trigger is stop then the voltage rises and it triggers again till again the voltage drops and they go off. Done fast enough you would see this as dimming and the worst the load increased the more off time there would be leading it to be dimmer. I'm sure I am wrong but it is a thought.

RJ

WakeFan
01-06-2008, 11:28 PM
I had the same issue when I wqas powering through cat5. After about 12 channels, the next one would dim, and the one after flicker.

Slush
01-07-2008, 11:31 PM
I also had this happen to me. I found that I was loosing some power over the cat5 and when I had all the channels on there was a few channels that were not "full on". I shortened the run between my 2 595's and the problem went away. It was most noticable on one SSR that had the longest cat5 run to it.

I believe that on the In/Out connectors there are a couple of unused pins. I am going to jumper them and double up my 5 Volt and qround lines. That may help with the "loss".

barrynash17
01-08-2008, 06:15 PM
Is there a chance that it is due to the ac mains load?
Anything else big running on the the same phase?
Just a thought.
Barry

daviddth
01-19-2008, 04:28 PM
I had a similar experience, but only when setting up the ren-c on my stripboard 595's. When powered by the parallel port on the laptop the voltage to the 595's was reduced to about 3.9V and everything worked fine.

When I went to the ren-c I decided to go back to the full 5V supply and nothing worked. I had good 5V or 0.4V outputs on the 595 boards, but the opto's just didnt want to work. Reduce the voltage back to 3.9V and it worked. After a little prodding & checking it turned out that I had a single +5V cable running to 32 SSR's (2 boards with 16 on each). Changing that to a slightly thicker cable supplying 1 board fixed the issue at 5V.

Since the SSR's are in the PC case along with the 595's and PC powersupply for +5v, I did not see that small cable as an issue and it did not affect the 2007 show, but changing back to the 5V and adding the ren-c caused the voltage drop in that cable to be worse, this effectively reduced the voltage to the point where the opto's would not fire.

Changing the 330 ohm (and some 180 ohm) resistors on the triacs also helped a lot in brightness of the lights. They went from OK, to "wow they are bright". Should make things better for the 2008 show I hope.

I'm also going to modify my external 240V SSR's so they are a little better designed, use a standard pin layout compatible with the grinch, except only 2 +5v and no earth as I need the other 6 conductors for the 6 SSR's.

We learn from our mistakes, and I have learnt a LOT from last years display ;)

Keith R
03-13-2008, 05:37 PM
All of you have more experience with this than I do, but I was considering using a Mean Well RS-25-5 power supply for my 2 595's. Here is the link:
http://www.meanwelldirect.co.uk/product/RS-25-5/RS-25-5/default.htm
It is very small and puts out 5 amps. Any 12 volt and other 5 volt needs would come from my computer.
Any thoughts on this power supply?
Thanks,
Roger

kmc123
03-13-2008, 06:13 PM
I got 6 of these for 7.99 each - AWESOME so far...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190184491630

jeff.ott
07-12-2008, 01:59 AM
I got 6 of these for 7.99 each - AWESOME so far...
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=190184491630


KMC123.

I just bought a few of these power supplies, but there were no instructions. . . . How do you wire them to a 110 source and where do you get the 5v wired from. Any help would be appreciated. . . :confused:

Thanks,
Jeff

omzig
07-12-2008, 03:05 AM
KMC123.

I just bought a few of these power supplies, but there were no instructions. . . . How do you wire them to a 110 source and where do you get the 5v wired from. Any help would be appreciated. . . :confused:

Thanks,
JeffI picked up a few of these also...

WWNF911
07-12-2008, 06:19 AM
Cool add Don!

kmc123
07-12-2008, 08:13 AM
I have the .pdf file on my site that shows all the specs...
It's located on:
http://www.kevincook.net/Hobbies/Electronics/Lights/PowerSupply/index.htm

omzig
07-12-2008, 10:38 AM
I have the .pdf file on my site that shows all the specs...
It's located on:
http://www.kevincook.net/Hobbies/Electronics/Lights/PowerSupply/index.htm
Indeed it is...that's where I got it. It's just a little confusing the way that the pinouts are shown. That's why I did the diagram. You're welcome to add it to the "Kevinapedia" if you want to.

jeff.ott
07-12-2008, 11:46 AM
Thanks guys. . . . I can continue on my way now. I get some of the molex connectors on my next order. Thanks again. . . .

Jeff

rstehle
07-12-2008, 12:12 PM
I get some of the molex connectors on my next order.

Just a reminder to anyone needing connectors that Molex has a "Sample" program, much like Allegro. They will send you free samples of connectors and pins.

kmc123
07-12-2008, 02:03 PM
Indeed it is...that's where I got it. It's just a little confusing the way that the pinouts are shown. That's why I did the diagram. You're welcome to add it to the "Kevinapedia" if you want to.

LOL:)
Added it to the "Kevinapedia" :)
Still smiling at that one!