[PSUBS-MAILIST] LED Lights

Al Secor via Personal_Submersibles personal_submersibles at psubs.org
Sun Jul 26 12:35:01 EDT 2015


Alan,

But then you would be excluding those with only a 24v system from using the max output...I assume the wide voltage input spec is to satisfy both
voltage systems.

Al Secor

--------------------------------------------
On Sun, 7/26/15, Alan via Personal_Submersibles <personal_submersibles at psubs.org> wrote:

 Subject: Re: [PSUBS-MAILIST] LED Lights
 To: "Personal Submersibles General Discussion" <personal_submersibles at psubs.org>
 Date: Sunday, July 26, 2015, 11:57 AM
 
 Ken,you
 are saying the LED operates from 21 to 45
 volts.If we had a switch that switched between 24
 & 36 volts in the hull,& an IC that
 detected the difference in the light housing,then
 we wouldn't need an extra wire / pin to initiate a
 changefrom 5000 to 10000 lumens.cheers
 Alan
 
 Sent from my
 iPad
 On
 27/07/2015, at 1:39 am, Ken Martindale via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:
 
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 #yiv3279730652   Sean,  There will not be any change in
 the LED intensity as long as the input voltage is between
 21.6 volts and 45 volts. We will tightly regulate the
 current into the LED array.  Noise on the power input may not
 be a problem within certain limits since the input EMI
 filter will handle a fair amount of noise.  If your slip rings break the power
 flow the light will continue to operate for about 3 to 8
 milliseconds or less. It won’t be damaged or degraded.
 Might get some interesting current surges
 though.  Can’t make a statement about the
 commercial drivers since some of them are low quality (they
 still mostly work).  Ken  From: Personal_Submersibles [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Sean T. Stevenson via
 Personal_Submersibles
 Sent: Sunday,
 July 26, 2015 8:52 AM
 To: Personal
 Submersibles General Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights  How sensitive are
 LED drivers to supply voltage stability? If I were to, for
 example, feed the LED light with 24 VDC that must first pass
 through a set of electrical slip rings, would any
 fluctuation in resistance or momentary interruption to the
 supply harm the light?Sean  On July 26, 2015 6:38:23 AM
 MDT, Ken Martindale via Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:Basically that’s the same
 for this light except it will shut off until it cools down,
 take a look at the spec. Ken From:
 Personal_Submersibles [mailto:personal_submersibles-bounces at psubs.org]
 On B! ehalf Of Alan James via
 Personal_Submersibles
 Sent: Saturday,
 July 25, 2015 9:21 PM
 To: Personal
 Submersibles General Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Thanks for that info
 Hugh.This extract from a manual below,
 is for a 700lm light. So heating as you say will be a big
 issue.How
 hard is thermal rollback Ken???..... 
 General Notes and Warnings The Nano SeaLite can be run in
 air, but will go into thermal rollback, where its light
 output diminishes to protect the light from overheating.
 This is normal and purposely designed to protect the LEDs
 from being damaged by excess heat buildup while running in
 air. The light will return to full brightness once it is
 submerged in water or it’s allowed to cool down. This
 thermal rollback will not happen when light is being
 operated in water under normal usage. WARNING When the Nano
 SeaLite is operated in air the body may reach temperatures
 in excess of 65° C. These temperatures may be enough to
 cause burns if the light is handled without protective
 clothing.Alan From: Hugh Fulton via
 Personal_Submersibles <personal_submersibles at psubs.org>
 To: 'Personal Submersibles General
 Discussion' <personal_submersibles at psubs.org>
 
 Sent: Sunday, July 26, 2015 12:34
 PM
 Subject: Re: [PSUBS-MAILIST] LED
 Lights 40
 degrees gives you 30 degrees120
 degrees! gives you 80 degreesIt
 doesn’t matter whether acrylic, Glass or borosilicate with
 flat planes.The
 only reservation on my lights is that I have not done a lens
 for the seawater to optimise angles etc.  Also my reflector
 is round with a square LED.Looks great in the swimming pool
 at night but as I haven’t dived it I have no experience as
 to how it will look in the sea. 
 With a really compact light and 94 watts of heat it is not
 going to last long in the air.  It will need serious
 fins.  Needs to be idiot proof.One
 thing is that it needs to have automatic dimming reduction
 for temperature so it does not desolder or destroy O⡍ rings etc.I
 will try and work out how the forum works and go to that. 
 I could not get into it but could view it. Hugh  From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Ken Martindale via
 Personal_Submersibles
 Sent: Sunday,
 26 July 2015 11:58 a.m.
 To:
 'Personal Submersibles General Discussion'
 Subject: Re: [PSUBS-MAILIST] LED
 Lights PS
 We are supposed to be discussing the LED light on the
 forum? ken From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Hugh Fulton via Personal_Submersibles
 Sent:
 Saturday, July 25, 2015 7:33 PM
 To:
 'Personal Submersibles General Discussion' <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Re-
 Dimming.Would it not be better to have 2
 switchable intensities rather than variable.  Then you can
 have a 3 position switch.  Is it simpler?Hugh  From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Cliff Redus via Personal_Submersibles
 Sent: Sunday, 26 July 2015 8:20 a.m.
 To: Personal Submersibles General
 Discussion
 Subject: Re:
 [PSUBS-MAILIST] LED Lights Yes
 we did but we had two members that were pushing hard for
 dimming. From feedback, we were two for and two against. 
  I would prefer not have it but if it makes the lite more
 generally accepted, I am willing to incorporate it.  This
 last version of suggestions are just that, suggestions.  A
 understand that nothing is frozen and we still do not have
 final consensus.  Cliff On
 Sat, Jul 25, 2015 at 3:13 PM, Ken Martindale via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:Cliff, Dimming, I thought we deleted
 this?Ken From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Cliff Redus via Personal_Submersibles
 Sent: Saturday! , July 25, 2015 3:29
 PM
 To: Personal Submersibles General
 Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Ken, I took you latest pass on
 spec and generated a one page summary.
  Cliff On
 Sat, Jul 25, 2015 at 9:48 AM, Ken Martindale via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:This light will require
 substantial cooling! . Total dissipation is about 94
 watts. Puts out a lot of light.
  Ken From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Cliff Redus via Personal_Submersibles
 Sent: Saturday, July 25, 2015 10:18
 AM
 To: Personal Submersibles General
 Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-M! AILIST] LED
 Lights Alan, my thinking is that with the
 flange, you could mount the light either way.  On the new
 boat I am designing, I am planning a FRP recess so that
 outside of the flange is flush with the outside of the FRP
 shell.  Would still need to cut a hole were the body passes
 through the FRP shell.  Yes this does reduce the convection
 heat transfer from the light but I was thinking of leaving
 say a 3/8 clearance around the recessed flange.  I
 don't see any problem with either approach to sealing on
 a MPB by using a neoprene flat
 gadget. Cliff On
 Fri, Jul 24, 2015 at 3:58 PM, Alan James via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:Cliff,I
 was thinking of fitting the light in to a bowl
 shapedrecess in the fairing / ballast
 tank, whereas you were proposingcutting a hole out & fitting
 it in. In hindsight your idea is
 betterbecause my idea would inhibit the
 heat dispersion due to the
 fiberglasssurrounding the light
 fitting.Alan From: Cliff Redus via
 Personal_Submersibles &! lt;personal_submersibles at psubs.org>
 To: Personal Submersibles General
 Discussion <personal_submersibles at psubs.org>
 
 Sent: Saturday, July 25, 2015 8:43
 AM
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Alan, I am visual kind of guy. 
 Can send me sketch of what you are describing and we can
 talk. Cliff On
 Fri, Jul 24, 2015 at 3:23 PM, Alan James via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote: Looks a good solid light
 Cliff.On
 looking at the perpendicular cable entry, I was thinking
 weneed a back entry for the purposes
 of mounting in to a housingin
 the fairing as you have requested in your
 list.I
 am looking at mounting in to ballast tanks so will create
 the shape of
 the light in the molding to receive it. If there was a
 threadedextension on the back of the light
 it could slot through a hole & be
 securedwith a nut. This would make it
 easier to seal off the ballast tanks
 inmy
 situation.Alan From: Cliff Redus via
 Personal_Submersibles <personal_submersibles at psubs.org>
 To: Personal Submersibles General
 Discussion <personal_submersibles at psubs.org>
 
 Sent: Saturday, July 25, 2015 1:55
 AM
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Ken, if you go to Youtube and do a
 search on https://youtu.be/D7VnwODU7vk,
 or 5000 Lumen Bridgelux Vero 18 LED light, you will see a
 short video of the light. Cliff On
 Thu, Jul 23, 2015 at 3:29 PM, Ken Martindale via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote: Cliff, How
 do I look at them?? Ken From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Clifford Redus via
 Personal_Submersibles
 Sent: Thursday,
 July 23, 2015 4:18 PM
 To: Personal
 Submersibles General Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Now
 that Jon has the forum site set up for the LED light
 project, my suggestion is to move the discussion to the
 forum site called out in Jon's email.  BTW, I have
 uploaded to the site the wiring diagram and housing drawings
 for the 5000 Lumen light that was designed by the ME
 students I was mentoring last
 year. Cliff On
 Thu, Jul 23, 2015 at 2:55 PM, Ken Martindale via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:Doing the dimming electrically is
 easy but the problem is the extra wiring and where do you
 mount the Potentiometer? We can
 include the wires in the cable for use as an option this
 also complicates the cabling. Instead of two wires we would
 require 4 wires. Personally I also like the dimming
 since it will extend the time you can use it out of the
 water. Anybody also like or dislike? Cliff would like to
 delete. You
 guys! be sure to keep reading the spec. it will have almost
 daily updates for a while. Ken From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Alan James via Personal_Submersibles
 Sent: Thursday, July 23, 2015 3:31 PM
 To: Personal Submersibles General
 Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Cliff,
 Ken,I
 like the dimming option. The 10,000 lumens may be too much
 light insome low visibility conditions
 where there is a lot of back
 scatter.The
 5,000 lumen option may act like a fog
 light.Also I am thinking of having
 lights mounted to the side which may
 notneed to be as
 intense.Depth rating.... looking at the
 drawings of various 10,000 meter light
 housings,it
 seems simple to achieve a reasonable depth without much more
 cost.Potting the board..... I would be
 careful about what was potted in case some of
 thecomponents needed to get rid of a
 bit of heat.Mechanical housing..... ! with you
 on that one Cliff. Like the idea of the recessed
 light.Alan From: Clifford Redus via
 Personal_Submersibles <personal_submersibles at psubs.org>
 To: Person! al Submersibles General
 Discussion <personal_submersibles at psubs.org>
 
 Sent: Friday, July 24, 2015 4:06
 AM
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Ken, good first pass at the
 specs.  Below are comments.  BTW, I will post these here
 as I have not been able to get the activation code back yet
 on registering at the
 forum. Item 2.1 DC Voltage.  If it were
 me, I would stick with nominal battery bank voltages of 24
 and 36 VDC.  When I switch to MK 101 thrusters, I dropped
 my main battery bank voltage to 36VDC my instrumentation bus
 is 24VDC.  Would need a single fuse holder to accept
 fuses to handle different nominal
 voltages. Item 4.0 Depth Requirement.  In
 the spirit of keeping cost down, I think 500 meters (1640
 ft) would be more than enough.  I know Scott is designing a
 deep diving boat but is any one else shooting for more than
 500m? 6.0
 Dimming.   I would omit the ability to dim the light. 
 Yes I know it is easy from an electrical point of view but
 it forces us to go with more pins on the subsea connector. 
 I am thinking on installing multiple lighs so I could just
 control on/off for each light.  I could go either way on
 this but in the spirit of KISS, I vote to omit
 dimming. 8.3
 Ports  I would change plastic to acrylic.  I don't
 think we will end up here but if we do, we can use PVHO flat
 view port calcs to size the acrylic
 lens. 9.0
 Printed Wiring Boards.  I really like the way the Minn-Kota
 motor controller PWBs are potted.  Rather than using the
 spray on hydrophobic coatings, to me we should pot the board
 (accept for access to fuse).  Therefore suggest changing
 the word coated to
 potted. 11.0 Mechanical Housing.  I
 suggest.  The LED panel light and PCB shall be contained
 in a single 1-atm flange mounted cylindrical housing with
 a low profile that can be recessed in a FRP shell with
 attachment screws from the rear of the flange.  The housing
 should contain a single 29 LED Array rated at 10,000
 lumens  with a rated power of  91-140
 lumens/W (109-71W).  Mounting holes will be provided for
 an optional SS yoke style support bracket. 
  Material: Hard anodized 6061-T6 or
 7071-T6  TBD (I have a grey beard machinist friend that
 owns a machine shop.  He loves 7071-T6 as it is a dream to
 machine and stronger than
 6061-T6. On
 Thu, Jul 23, 2015 at 9:52 AM, Ken Martindale via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote: Cost is critical. The electronics
 should be a small part of the cost. The housing might be the
 most expensive. Hope you guys are reading the
 specification. Ken From: Personal_Submersibles
 [mailto:personal_submersibles-bounces at psubs.org]
 On Behalf Of Clifford Redus via
 Personal_Submersibles
 Sent: Thursday,
 July 23, 2! 015 10:18 AM
 To: Personal
 Submersibles General Discussion <personal_submersibles at psubs.org>
 Subject: Re: [PSUBS-MAILIST] LED
 Lights Jon, thanks for setting up the
 forum.  I am assuming we can post files as
 well. &nb! sp;I agree low cost is
 important but having a functioning light is as well.  OTS
 LED utility lights like that one you noted are not an option
 unless they can be potted.  To me the best way to keep the
 cost low, is to publish construction drawings of a 1-atm
  DIY housing that a psubber could machine or have machined
 by a friend, and publish a design of a PCB that could be
 easily fabricated using  one of the PCB online sites like
  ExperessPCB www.expresspcb.com and
 DIY populate the board.  As a group, we design and build a
 prototype that I can test in my shop. If it works as
 designed, then we post to the psubs site a report, that
 includes the design drawings, circuit diagram, parts list
 and test
 results.  Getting a consciences on the
 design spec is the first
 step.  Cliff On
 Wed, Jul 22, 2015 at 10:11 PM, Jon Wallace via
 Personal_Submersibles <personal_submersibles at psubs.org>
 wrote:
 My three words of advice...cost, cost, cost.
 
 One measure of a success for
 this project will be how many people actually build/use
 it.  If it costs more to manufacture than just purchasing
 something like http://www.surpluscenter.com/Electrical/Lights/DC-Mobile-Equipment-Lights/12-24-VDC-3120-LUMEN-16-LED-UTILITY-FLOOD-LIGHT-12-999-B.axd
 off the shelf then it's real world application by
 psubbers may be limited.
 
 Over-spec'ing the design above requirements
 for typical recreational operations (ie 10,000 psi
 capability) is likely going to drive up the cost.  Also,
 let's remember that "cheap", "low
 cost", and "good price" are relative terms
 for a diverse group like PSUBS so include realistic
 estimates of parts and manufacturing especially if tooling
 is required.
 
 Jon
 
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