CCD Peltier Cooling - power requirements?

[[1ponders]]

I've just put in an order for an ATiK 16IC and after placing the order (isn't it always the way :rolleyes: ) I started to think about whether I should have gotten the AC adapter.

According to the spec, even though it has a jack for external power, the camera draws it's power through the USB port. Will the USB be able to supply enough power to the Peltier. I don't know much about them but I would have thought that cooling to 25d below ambient would require a fair bit of juice.

Can anyone (DP, bird Gary B) enlighten me on this.

[gbeal]

Ponders,
if it is anything like the GamaCam (QHY) the peltier draws a heap of juice.
What makes me think they have the AC jack is that when you use another power source, as opposed to just the USB, then the peltier will run at full steam. With just the USB I can't see you getting the whole cooling effect, BUT...... that is just a guess. Did you ask the supplier. I read a great rave about how good this camera is for auto-guiding.
Gary

[[1ponders]]

It took me a few days to talk myself into it Gary (after kicking myself for missing richardo's Starlight Xpress the other day), but yes you are right I've heard good things about it and some of the images are pretty special. I'm looking forward to some clear skies after I get it to put it to good use. :rofl:

I guess that I would be able to pick up an adapter to suit from here somewhere np. Problem is these buggers that sell this stuff online don't include much in the way of specification. Even when I click on the link for the adapter accessory it give no details just "ATiK adapter" :lol:

[[1ponders]]

This is the camera I ordered ATiK 16 IC-HS (http://www.telescope-service.com/atik/start/atikstart.html) (but not from them. ). If you look up the page you will see the ATiK 16 and ATiK 16HR and their peltier requires 12V and 0.8 amp

[mill]

The peltier will not be powered by the usb port , only by the adapter.
Without the adapter it will not be cooled.
If memory serves me right the usb port can deliver a maximum of 500mA at 5 Volts.
Hope that helped a bit :)

[gbeal]

Paul,
mill has in essence confirmed what I guessed at. I too reckon you need the adaptor, or a power adaptor of some sort.
For some reason I thought this chip was similar to the ST7, but it is only ToUcam sized. No matter.
One guy that will know and is probably just un-slumbering, is Arthur (ambermile). He will no doubt be reading this with his Weeties, so expect an expert answer soon.
Gary

[bird]

yes, peltiers do chew a lot of current, so I can't see any way that the usb port can be powering the cooling...

cheers, Bird

[[1ponders]]

This is the one that is advertised

http://www.astrovid.com/prod_details.php?pid=2719

But it doesn't give any details as to the output. 12V I assume but how many amp? And for that price what sort of comparison would I expect here in Aus (if anyone knows)

[[1ponders]]

I you check out this page
http://www.trifid-optics.com/ccd-atik.htm#ATK-16IC

it mentions a universal power adapter :rolleyes: but further down in the specs the power is given as 12V 0.55A. Would this be just to power the chip or would that be enough for the Peltier?

[Dennis]

Hi Paul

I have the Orion Star Shoot Deep Space that is USB powered for imaging but requires a (user purchased) mains adapter for the thermo electric cooling (Peltier). I use a regulated 12VDC 2A unit, centre positive, purchased from Jaycar for around $30 IIRC.

Cheers

Dennis

[[1ponders]]

Thanks Dennis, sounds cheeper than getting it in from the States :P Well I already have a regulated 12V 2A power source and the camera comes with a "Car lighter plug adapter (for battery use)" so I should be sweet.


Any idea how much your peltier draws Dennis?

[Dennis]

Hi Paul

Hmm, I don’t know the answer to that, but from memory, I believe a 12VDC 1A mains adapter would have been adequate?

My SBIG ST7E mains adapter has dual outputs of 12VDC at 500mA and 5VDC at 2.0A. It has x2 chips (imager & guider) and I think the 5VDC is for them, so the 12VDC at 500mA is more than likely for the Peltier?

The ST7E has a regulated temperature setting where you can set the value and it will maintain it at the set point, whereas the Orion just runs flat out with no temperature regulation.

Cheers

Dennis

[Ambermile]

Good morning people (just chomping my weetoes here) and you're pretty much right, a 12v 2A will be plenty. 1 amp would do but there's that unwritten rule about double your need. To tell the truth, any voltage down to about 3.5 will run the peltier as it's current we are interested in here... if you run a lower voltage you will get less cooling - simple. Best to stick to the design spec though of 12v to ensure you can get the chip down to that 20+ degrees below ambient.

Also, the ccd is *not* Toucam-sized, but rather it's the significantly larger ICX424ALL (BW) or ICX424AQ (colour)

The ART285 and ART429 both have 12v and 5v supplies, the 12v is for the camera and the 5v is for the cooling. Atik altered this for the sake of simplicity in the 16 and 16HR by using a regulator inside the camnera to drop the 12v line to 5v.

Arthur

[[1ponders]]

Thanks Arthur. :thumbsup:

From the specs the chip size is given as 659x494 @7.4 micron pixels. 6mm diagonal chip I believe.

http://www.trifid-optics.com/ccd-atik.htm#ATK-16IC

Although this site gives the specs as 640x480

http://www.telescope-service.com/atik/start/atikstart.html#CCDKam