Artist seeks electrical advice

ehsjr wrote:


Not yet...

It's distributed by a place in the Bronx but made in China. I found it online and I can get a replacement cheaper at: http://www.djdepot.com/chauvet-rlc737-chase-controller-p-486.html?osCsid 295eeb34fb3ec1cee1a861d50c2318
If that doesn't work you can google it: RLC-737 Plus. It comes up as Chauvet on the first link, but mine is from Lighting Effects International, so it's an "LEI"

Interesting. I like #2 but I think it might be weird -- even though I have 4 channels the total height is 6 lights (meaning channels 1 and 2 are on the outside of the sunrise, as well as on the inside). But I know #1 works--at least when it's fast enough, you don't think about that. Let's say #1.
To throw something else in the mix, I'd like to light 7 more red bulbs of the same kind (on the head band) on either a separate line that's always on, or on S1 (first choice) or S4 if we go with scenario 1. Also if this is ridiculous it can be its own line. But ultimately a fog machine might be connnected and all of that would mean 3 plugs... probably too much.

Less than a second I think. 3/4 of a second, maybe? I had not really thought about this. Let me know if I have to decide.

Well that's definitely within the budget although I won't hold you to it. I talked to one guy at my favorite electrical store in Chinatown and he said I was going to need a transformer that would cost about $600 PER LINE. And that I could use a transformer from Radio Shack but there would be lots of humming. But he also told me I could not string together LEDs. So I am not following his advice right now.
Thanks! Heidi

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
artfrogger wrote:

http://www.djdepot.com/chauvet-rlc737-chase-controller-p-486.html?osCsid 295eeb34fb3ec1cee1a861d50c2318
I looked up the parts. They come to $21.89, but I'd opt for another ~4 dollars to accomodate the extra bulbs. That's the good news. The bad news is that's using 3 different mail order houses - which means 3 separate shipping & handling charges on top of the parts price.
I was hoping to get lucky at one of the suppliers where all the parts would be available.
And the parts price doesn't include a cabinet or any hardware or wire. Ingenuity comes into play with that - scrounging an old cabinet & line cord and having some screws and nuts on hand.
When do you need the thing?
Also, I have to believe the store in Chinatown did not undertsand what you need. 600 dollars? Sheesh! Well, mayber they are figuring the subway token to deliver it to the museum (?) on 26th street. That leaves what - $598.50 for one transformer? I'll be shaking my head for a long time over that one.
If you are interested in the parts breakdown/price, let me know and I'll post it or Email it.
Ed
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Great! Yes please, let's see what all the stuff is and I'll order it. The wait is fine as I am adapting the headband piece to be a 3D ring of steel instead of a 2D piece of wood. I don't get that headband back till Wed, and then will be "rebeading" for days...and I also need to build a frame behind this whole thing for it to hang on the wall and contain the fog machine. I have lots of work to do on this, but I don't have a deadline.
I was hoping that guy didn't know what he was talking about with the $600 step down transformer, or whatever it was.
Thanks! Heidi
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
artfrogger wrote:

Ok. I made low cost the priority, followed by ease of assembly. At the end I added a couple of options that raise the cost a bit, but are worth considering.
First, we'll use the 120 volt outputs from your controller like this, one wall wart and relay per channel:
------------ Controller | ------- 120V =| 9V DC | ----- | | wall |===|Relay| | | wart | ----- | ------- RLY-426 ------------ DCTX-915
Above parts are from Allelectronics: DCTX-915 4 @ $2.50 = $10.00 RLY-426 4 @ $0.75 = $ 3.00 http://www.allelectronics.com/ Also, you'll want a perf board to mount the relays - something I forgot earlier. Thats another $2.00, catalog # PC-4 from them.
Next, we'll use a 24 volt, 4 amp transformer like this:
------------ |Transfromer |-----> To string 1, 2, 3, 4 and 5 common 120 ---| 24 V | VAC ---| 4A |--- no connection | #7845 TR | | From MPJA |---+------ Rly 1 contact ------------ | ^-------> To bulb string 1 | | +------ Rly 2 contact | ^-------> To bulb string 2 | | +------ Rly 3 contact | ^-------> To bulb string 3 | | +------ Rly 4 contact | ^-------> To bulb string 4 | | +-------------> To bulb string 5
The transformer is part # 7845 TR at $8.49 from MPJA http://www.mpja.com / It's an upgrade from the 2 amp transformer, and will support the additional string of 7 bulbs.
Next, the bulb strings and resistors:
String 1 ---+---[5ohm]---[1.5ohm]--B--B--B--B--B---+ | | +---[10ohm]------------B--B--B--B------+ | | String 2 ---+---[10ohm]------------B--B--B--B------+ | | +---[10ohm]------------B--B--B--B------+ | | String 3 -------[5ohm]---[1.5ohm]--B--B--B--B--B---+ | | String 4 -------[10ohm]------------B--B--B--B------+ | | String 5 -----------------------B--B--B--B--B--B---+--- Common
Resistors: 2 @ 1.5 ohms, 5 watts p/n 280-CR5-1.5-RC $0.39 ea $0.78 2 @ 5 ohms, 10 watts p/n 280-CR10-5.0-RC $0.55 ea $1.10 4 @ 10 ohms, 15 watts p/n 280-CR15-10-RC $0.63 ea $2.52 Total $4.40 from Mouser http://www.mouser.com /
Overall total: All electronics $15.00 MPJA $ 8.49 Mouser $ 4.40 ==== $27.89
Ok at that price there are 2 questions: First, and most important: can you wire this? Second, can you spend a little more? Remember, there will be 3 shipping&handling charges added.
But I would highly recommend a few simple additions: 1) You must add a fuse in line with the 120 volt power to the MPJA transformer. You may also want a switch. A 2 amp fuse and a fuse holder: holder # FHPM-47 $1.00, fuse # FS-2 5 for $0.75 from Allelectronics An MTS-4PC toggle switch is $1.00 there.
2) It would be a good idea to reduce the voltage slightly - that will protect the bulbs a bit. Adding a .5 - 1 ohm resistor to each string or sub-string consisting of 4 or 5 bulbs will reduce the voltage to each bulb by about .2 or .25 volts for the 1 ohm or about .1 or .125 for the .5 ohm. I would order 6 of each 280-CR5-0.5-RC and 280-CR5-1.0-RC. At 39 cents each, that comes to $4.68. You can then experiment to see if the bulbs glow brightly enough with a 1 ohm resistor added to the group of 4 or 5. If they do, use that resistor. If not, try the .5 ohm resistor. This requires the artist's eye. The "engineering eye" wants the bigger resistor. :-)
3) There will be a short delay between the time your controller switches a channel off and the time the lights turn off. The simplest way to keep that delay short is to add a 100 ohm resistor in parallel with the relay coil. 282-100-RC at 19 cents each from Mouser will total 76 cents. It may be a worthwhile addition.
The relay wiring requires that you are able to determine what pins on the relay are the coil, and what pins are the contacts. Do you know how to do that?
Ed
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
in the past I have modified these low cost chase units to us low voltage. it take only one transformer and you merely cut the 120 VAC source to the internal TRIACS and replace with the lower voltage transformers secondary. unfortunately this pretty much violates whatever UL rating, therefore it was for my own amusement in creating a disco chase with 24 volt mini par cans.
another option would be to rewire the light zones to series-parallel in groups of 2 lamps and use 6 volt transformers, one per output. these are commonly used in PAR 36 pin spots.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
transformer for $16.95 each. that leaves 6 volts to drop which you can do by adding 2 more lamps in series per string.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Paint the lights you don't want to use black.
sQuick..
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Wow, thanks everyone. I clearly in the deep end, but hopefully I can find my way out. The controller has 4 channels, each of which says 300W and there is a toggle switch that says AC line and I can switch back and forth between 110v and 220v. Each light string says 125V1A on the plug. String 1 has 8 exposed lights; string 2 has 9 lights; 3 has 5 lights; 4 has 7 lights. The form is a concentric 1/2 circle of lights with 6 "rings", thus the crazy numbers.
Stupid question: when I plug it into a regular US outlet, is it 110V?
Thanks--ther is so much information since I last checked that I am going to reread it and try to get my head around the new info.
Heidi
I really appreciate all the advie sQuick wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
yes US power will be 110V from a normal house outlet.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
artfrogger wrote:

With a shortened string and resistance to make up for it: String 1 needs 97 ohms at 100 watts String 2 needs 93 ohms at 100 watts String 3 needs 107 ohms at 110 watts String 4 needs 111 ohms at 115 watts
That will produce about 100 watts extra heat per string - way too much. The wattage makes that solution impractical, so a different solution is called for.
With 2 18 VAC 2 amp center tapped transformers, #7843 from http://www.mpja.com/ at $4.63 each, 4 relays and some resistors you can build what you need. You will make assemblies of 4 bulbs in series. String 1 (8 bulbs) is made from 2 assemblies in parallel. String 2 (9 bulbs) is made the same way, and an additional bulb is switched in with a relay. String 3 (5 bulbs) uses 1 assembly with an additional bulb switched in via a relay. String 4 is one assembly. The diagram is shown below.
+----------------------+ | | | 9VAC(T2) | | | | 18V(T1)-+----------+ +--------+ +---+--------+ | | | | | | [R1] [R2] [R3] [R4] [R5] [R6] | | | | | | |<|Ry1-1 |<|Ry2-1 |<|Ry2-2 |<|Ry3-2 |<|Ry3-1 |<|Ry4-1 | | | | | | +-+--+ +-+--+ | | +--+ +--+ | | | | | | | | [B1] [B5] [b1] [b5] [b9] [B5] [B1] [b1] | | | | | | | | [B2] [B6] [b2] [b6] +--------+ [B2] [b2] | | | | | | | [B3] [B7] [b3] [b7] | [B3] [b3] | | | | | | | [B4] [B8] [b4] [b8] 9V(T2) [B4] [b4] | | | | | | 18V(T1)-+----+-----+----+---------------------+--------+ String1 |<--String2-->| |<String3>| String4 B1-B8 b1-b9 B5,B1-B4 b1-b4
Wire your 4 channel controller to operate the relays, Ry1 through Ry4. You will need to select relays that operate on the voltage your controller provides. Relays 2 and 3 need to be double pole relays. The bulb strings are wired to the normally open point, and the dropping resistors (R1 through R6) are wired to the respective operating points.
Resistors R1,R2,R5 and R6 are each 5 ohm, 10 watt resistors. You may want to add a 20 ohm 5 watt resistor in parallel with each of them to make the bulbs a little brighter. R3 and R4 are 6 ohms each - you make each of them with a 5 ohm, 10 watt resistor in series with a 1 ohm 2 watt resistor.
A word on brightness: dimmer is better than brighter. You want each of these bulbs to glow dimmer than any single bulb in a regular 35 bulb string. You can dim the bulbs if necessary by adding resistance in series with R1 - R6. Add a 1 ohm 2 watt resistor in series to make it dimmer. If that dims it too much, add a second 1 ohm resistor in parallel with the first one ohm resistor you added.
Ed
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.