Group Buy: Budget CRI 95 LED Strip Lights

[Robert Andriessen]

The point is that a cable of insufficient current rating when carrying a current of 10A can get excessively hot. When enclosed, the lack of convection cooling will increase that heating. A coiled internal cable, as is often used internally for audio boompoles will also increase resistance and heating.

Remember microphone cable only has to carry maybe milliamps at millivolts, so current rating of the cable is generally barely a consideration for that application. Fortunately, low resistance is desirable to minimise voltage drop here, so audio cable will be thicker than necessary for the tiny audio currents.



Edit: A casual glance at a few mic cable specifications would indicate that they are not rated anywhere near 8A, let alone 10A, and that's in open air. Will do a bit more research to double check, but looks inadvisable to use mic cable for this purpose!

thanks for checking, that's good to know how thin the cable running through the boom actually is.

 

[Alvise Tedesco]

Brandon, what about recapping all the news about tubes, balls, etc on original post?
67 pages takes time to read
Cheers

 

[ericyoung]

So maybe another option would be to still get a sound boom pole with internal mic cable, and then disassemble it and replace the cable with a proper electrical wire. This way we could keep the convenience of not having to gaffer-tape wire to the outside of the boom each time we want to use it.

Yes, sure, but you don't need to gaffer tape cable to the boom - just look at how Sound Boom Operators handle external mic cables - it's not hard. An external mic cable is also easier to replace/fix if it goes faulty.

 

[Antony Newman]

XLR cables used to be use to power (high current requirements) loudspeakers. But this group then moved to 'Speakon' (and other) cable types.

Nowadays XLR cables are mostly designed to have good electrical insulation to avoid voltage signals 'bleeding' from one cable (channel) and the next cable.

They can accomplish this through thin (or thick) conductive cables.

If they are thin .... they have more 'resistance' to the flow of electrical current .... and HEAT up;
This HEAT could be hazardous - ie could melt / cause something to catch fire ... Inside a Pole.

XLR cables can handle 2-12 Amps according to this Wiki:
http://en.m.wikipedia.org/wiki/XLR_connector

My recommendation would be to check the rating of the existing XLR cabling with the manufacturing.
Or rewire (as has been suggested)

AJ

 

[Brandon J.F.]

Speaking of amps...

While our budget controllers/dimmers were being customized an issue came up. The higher they raise the PWM frequency (to make it flicker free) the more the amps have to go down or things get too hot. So, what is more important to you guys? Flicker free slow-motion or a higher amp rating? The higher the amp rating the longer our strips can be. There are amplifiers we can get also that are relatively inexpensive (~$32) and/or we can upgrade to a slightly larger unit (still quite small in size) for ~$17. Personally, I would prefer a beefier unit and the option to use an amplifier both, but I want to hear what you think. I've talked about these amplifiers privately with a few of you who want to build multi-spool larger rigs.

They have a team working on this for us. Let me know your thoughts...

 

[Jordan Raabe]

Lets go beefier.

 

[Martin Stevens]

Beef.

Also..... Brandon, did you get my PM?

 

[Phil Holland]

I enjoy beef.

 

[Ken Willinger]

Beef (grass fed of course).

 

[ericyoung]

Can the dimmer we're getting at the moment handle a full 5m strip at 10A flicker free? What's the PWM frequency you get with that? I'd like to be able to light something at least up to 100fps without flicker with a full strip at full brightness. But 120fps would be better.

 

[Larry McKee]

Tubes and China balls would be great. Please add me to the list.

 

[Patrick E. Coker]

I'm a beef man

 

[Brandon J.F.]

Can the dimmer we're getting at the moment handle a full 5m strip at 10A flicker free? What's the PWM frequency you get with that?

No, 10 amps and flicker free is too much for it. The PWM freq would be too low.

I'd like to be able to light something at least up to 100fps without flicker with a full strip at full brightness. But 120fps would be better.

I would love that, but it may be too much for a $50 budget controller. They are still tweaking things though.

I'll keep everyone updated.

 

[Poi Boy]

Beef here

 

[Manfred Lopez]

Beef!

 

[Brandon J.F.]

Tubes and China balls would be great. Please add me to the list.

Here's everyone that's on the preliminary list for light tubes:

HD Hildebrand
Steve Smith
Andrew Wonder
Brian Pascale
Daniel Doherty
Larry McKee
Bing Bailey
Cristian Mihai
Jamon Lewis
Loren Simons
Kelsey W. Smith
Daniel Murphy
Mikael Lubtchansky
Nick Morrison
Michael Ou
Carey Lee Coffey
Terry VerHaar
Martin Stevens
Eric Santiago
Wynn Ruji
Mark Stock
Shane Kelly
Eli Jarra
Susan Lumsdon
Peter Stepnoski
Manfred Lopez
Zhen Jie
Brooks Moore
Note Suwanchote
Antony Newman
Dominik Novotny
Lance Kaplan
Tony M
sam karr
Nils Ruinet
Kirby Hamilton
Jack Smith
Bob Gundu
Herbert Massey
ericyoung
Frank Weeks
Brad Crawford
Poi Boy
Scott C
willy apex
Bruce Allen
brian leisring
Terry Delahunt
Paul Hazlett
Ken Willinger
Med D
Ces Peynetti
Mike Smith
steven moreno
Stephen Pruitt
jeff Hornbaker
Nick Morrison
John Wee
Paris Remillard
Larry McKee


The manufacturer just sent me a picture of the light tube samples that are coming my way. Hopefully I'll have them Monday or Tuesday.

Looking forward to playing with these. If you missed all the talk about light tubes go back a few pages. Basically you put a strip of LED inside and you have an ultra-portable kino flo-like tube. High CRI, powerful, and portable. Very useful for cars, on location, run and gun lighting, anything...

 

[Med D]

I'll take a tube and china ball as well.

 

[HD Hildebrand]

bring on the beef

 

[Mike Smith]

No, 10 amps and flicker free is too much for it. The PWM freq would be too low.

Brandon,

Is that at any frame rate, or are you talking specifically of high frame rates here?

Do you happen to know what PWM frequency the manufacturers are talking?

Thanks.

 

[Brandon J.F.]

Brandon,

Is that at any frame rate, or are you talking specifically of high frame rates here?

Do you happen to know what PWM frequency the manufacturers are talking?

Thanks.

At any frame rate. 10A is a lot to expect from a $50 dimmer. LG's standard dimmers are only 8A.

The PWM freq will be somewhere between 2,000 and 5,000.