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ArcticMyst Security by Avery

Blu-ray with TEC!

jayrob

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Thanks! I am going to go ahead and post pictures as it progresses in case anyone wants to follow this build some day. I think it is well worth the $300 bucks that I'm spending on this new one (with FlexDrives).

A guy could easily build a similar design using cheaper parts. (like AixiZ module instead of Meredith, different drivers, different batteries with no need for a LiPo alarm)

The peltiers are cheap. So is the box, fan, and heatsink. :) The big expense is because I want to use a Meredith glass lens, FlexDrives, and the twin LiPo's with alarm.

The main parts are already linked a couple of posts above.
Jay
 





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I think I've been inspired, I never knew those things were so cheap.

How do you run the peltiers, just with a normal driver for a laser diode? So that would be two drivers then, one for the diode and one for the peltier, right?

Also, do you know any links to BIG peltiers :) I want a massive one, just because it would be awesome :D Biggest I found on eBay was a 62mm one with 545Watts or something. Only $30! Wow, I just want to get one of these with a heatsink and fan and just have an instant freezing metal plate. How awesome would that be :cool:
 
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The main thing you need to remember about a TEC used this way is that it
is a Heat Pump. It takes heat from one side and pumps it to the other side.
It works on the differential of the hot and cold sides and of course the amount
of current you supply to it.
So... if you cool off the hot side with a heat sink and fan... the cold side will
get colder. ;)
 

jayrob

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Murudai said:
How do you run the peltiers, just with a normal driver for a laser diode? So that would be two drivers then, one for the diode and one for the peltier, right?

Also, do you know any links to BIG peltiers :) I want a massive one...


I just tested this peltier (the one I linked above), using a FlexDrive with a 7805 voltage regulator. First I set the current on the FlexDrive with a rkcstr test load for a red diode. Then I set up my DMM with the peltier connected up. The current setting was the exact same as the test load! :)

I have not used any different peltiers other than these ones. But it seems to be of good size!



Next steps! - Here's some more pictures as this new build progresses...

IBtut7.jpg

Dual FlexDrives mounted with easy access to the pots! ;)

IBtut8.jpg

Here you see the 7805 regulators. There are a couple of things I would like to mention here...

* I figure that probably just one regulator could have been used to power the two drivers as well as the fan, but I found them to be a nice way to mount the Flexdrives! They are cheap enough anyway...
* Notice the thin Mica sheet in between the peltier and the 7805 regulators. (to give a little insulation there)
* Notice also the little heatsink on top of the metal (heatsink) parts of the 7805 regulators... I put this there for two reasons, to give some more heatsinking for the regulators, and also to further 'stabilize' the build, linking the two drivers together and making the mount strong. (The metal back/heatsinks on the 7805 voltage regulators, are 'ground', so they can be connected together. Since the drivers are running in parallel from the same battery supply, they are already electrically connected)

IBtut9.jpg

The Meredith mounting block has the set screw on the side. This won't do, because when it's all together, you can't get to the set screw. So, just a little modification to the block...

IBtut10.jpg

The 5 volt fan will be given it's own regulator too! Might as well, they are not expensive.

More to come...
Jay

Note: At the finish of this project, I found that using 3 separate 7805 voltage regulators robbed too much of my supply voltage. So, the fix was to run only two separate voltage regulators. One for the Peltier driver, and the other one runs both the fan, as well as the driver for the LD. Works perfectly!
 
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so whats the reason for using a driver on the peltier plate? they are made to work with 5-12volts?
 

jayrob

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That's a good question Josh, and I hope someone can chime in on this one, but I originally went with suggestions from Gazoo.

He was running this peltier with an AMC7135 driver at 350mA's. So I never questioned it, but I built my design with an adjustable driver so I could in effect, 'tune' the cooling, depending on how much I turned up the LD current.

I believe that if the hot side of the peltier is cooled properly with a finned heatsink and fan, that you could actually have too much cooling on the 'cold' side of the peltier. Maybe even get it iced up...
Jay
 
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hmm that is a good point i did some experiments with my plates (same as your)

and it was with a 9 volt dc wall plug and it got quite cold but no condensation or anything. i will do some longer test after i finish modding my heat sink.
 

jayrob

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Did you have a heatsink and fan on the hot side? Because I don't think it is good for the peltier to run it without cooling the hot side.

...and of course, it won't get anywhere near as cool on the cold side, if the heat is not being dissipated.
Jay
 
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yes sir i found some little fans that fit perfectly into the heat sink.

also it makes the heat sink quite warm and the cold side heat sink very cold!

i have a question. what are you using to glue the heat plate to the heat sink? i used arctic silver 5 but it doesnt stick very well, should also use the ceramic arctic silver?

or what? i have a way that i will be screwing it all together to press fit it very tight but i wasnt sure if you had a better experience or way :)

thanks
 

jayrob

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thesk8nmidget said:
i have a question. what are you using to glue the heat plate to the heat sink? i used arctic silver 5 but it doesnt stick very well, should also use the ceramic arctic silver?

Just using a very thin layer of Arctic Silver adhesive. (not number 5 - this is just a thermal compound, not an adhesive)





Jimmymcjimthejim said:
Wow! The project is looking good so far  :cool:

Thanks man! I just finished up the wiring. Seems to be the most tedious part...

IBtut11.jpg

IBtut12.jpg


Just waiting for the batteries to get full charge so I can set the LiPo alarm. There's a dip switch that you toggle at full charge so that the alarm knows what full charge is. (this is a one time thing, then it remembers)

I should be testing it in an hour or two! :D
Jay
 
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it's... beautiful!!! :'(

The wiring makes my head hurt >.<
Amazing build, though!
 

jayrob

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Thanks!

Just got it all buttoned up!

IBtut13.jpg

IBtut14.jpg

IBtut15.jpg


I did some initial testing with good results....


The good is great! At 186mA's, I got 183mW's steady through the Meredith glass lens! This must be an extra nice diode :D...

Normally, I would expect maybe 175mW's, even with the Meredith glass lens. Then again, I never have ran an 803T at this current before...

There is one thing... I just have to re-wire, or change to a 3S 11.1 volt supply.

When I first tested for somewhat normal current (to make sure the fan and peltier were all working), the diode put out normal (expected) readings. But when I turned it up to 186mA's, I still only got about 114mW's??

So, I disconnected the twin 7.4 LiPo's, and plugged in an 11.1 volt LiPo. After re-setting the current to 186mA's, I then got the good results. (183mW's)

Help... It would be easy enough to by-pass two of the 7805 voltage regulators, and wire everything off of a single 5 volt regulator, instead of using 3 separate regulators. (I suspect that three are sapping my supply voltage)

Does anybody know if it would be ok to run 2 FlexDrives, and a 5 volt fan in parallel off of a single 7805 voltage regulator? I would think that this should be just fine. But I sure would like to hear it from someone before I cut the leads going to the two 7805's at the peltier. (It would then be easy to solder wires to the input on the two drivers, and they can connect to the voltage regulator where the fan is connected)

It's either that, or I will try to find an 11.1 volt LiPo that will fit my new Ice Box...
Jay
 

jayrob

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I just found some information on the 7805 voltage regulators that I bought. And it says that the 5 volt output is up to 1 amp...

I have my peltier set at 546mA's, the fan draws about 192mA's, and I want to set my LD at 186mA's. This adds up to 924mA's. :)

Armed with this information, I am going to go ahead and do some adjustments in my wiring to disable the two regulators at the peltier and LD. (or maybe just one of them) Then I will bring leads from the 7805 voltage regulator at the fan, to the FlexDrives and power all three components from the single voltage regulator.

I'll report back soon...
Jay

Update.... Schweet success! I only disabled one of the 7805 voltage regulators. The peltier driver has it's own. The LD driver and the fan share another now.

No more inconsistency! ;) (I think that I may have had some driver current inconsistency with the 11.1 volt supply testing)

Now it is very stable with my twin 7.4 volt LiPo packs in parallel. I did a 5 minute run at 186mA's. It was rock steady at 178mW's. The temperature of the block DROPPED 2.5 degrees during the 5 minute test run! :D It was noticeably cooler to the touch.

Awesome!
Jay
 

jayrob

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I'm now the proud father of healthy twins! I'm going to leave the settings as they are for a while and see how it goes...

I am amazed at the result of the 5 minute test run of the blu-ray Ice Box @ 186mA's! To go for 5 minutes at this current, and the temperature of the Meredtih mounting block actually got LOWER! :D

IBpair.jpg


I know.... all the labels and stuff look kind of 'cheesy'. But it's important information to keep track of. This way, I don't have to go looking for it...
Jay
 




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