Powering a cooled camera

[Erling G-P]

Hello all,

Have just acquired a 2nd hand Primalucelab Canon 700Da (cooled).  Had originally imagined I would power it with the Skywatcher 17Ah Powertank I use for my HEQ5 (and intend to use for the Synguider 2 I'm trying to get up and running)

Got worried by the manual stating that the cooling requires a 12V 5A power supply - that seemed like a lot of current.  Set about measuring it with my multimeter, using my Powertank.  Showed a current draw of 3.6A.  I let it run until it reached the set temperature of -5ºC, wanting to see if the high current draw was only during the initial cooling to reach the desired temperature.  While it did start to fluctuate a bit, along with the fan speed, it did seem to hower around 3A.  At this point I realized it had almost melted the wires for my multimeter!  They were glowing hot and completely soft, so terminated the experiment immediately.

With the high power consumption, I'm worried my powertank will be drained in a few hours, if I use it for the camera. As mentioned above, I'm also trying to start guiding, and have been told this will considerably increase the power consumption of my mount, adding to the problem.

Presently, I'm imaging from my garden, so do have access to mains power.

Have asked Primaluce for a recommendation, and they suggested a heavy duty car battery for powering everything.  Not too keen on having to haul a heavy car battery back & forth in each session however.

Also asked 365Astronomy who sold the camera originally.  They suggested using my Powertank, stating to have used just such one for such a camera.

Figure the cooling must work on the same principle in other cooled cameras, so expect them all to have high power demands, and so wondering; what do you guys with cooled cameras use to power them ?

Thanks in advance for any answers.

 

Regards,

Erling G-P

[Adam J]

12 minutes ago, Erling G-P said:

Hello all,

Have just acquired a 2nd hand Primalucelab Canon 700Da (cooled).  Had originally imagined I would power it with the Skywatcher 17Ah Powertank I use for my HEQ5 (and intend to use for the Synguider 2 I'm trying to get up and running)

Got worried by the manual stating that the cooling requires a 12V 5A power supply - that seemed like a lot of current.  Set about measuring it with my multimeter, using my Powertank.  Showed a current draw of 3.6A.  I let it run until it reached the set temperature of -5ºC, wanting to see if the high current draw was only during the initial cooling to reach the desired temperature.  While it did start to fluctuate a bit, along with the fan speed, it did seem to hower around 3A.  At this point I realized it had almost melted the wires for my multimeter!  They were glowing hot and completely soft, so terminated the experiment immediately.

With the high power consumption, I'm worried my powertank will be drained in a few hours, if I use it for the camera. As mentioned above, I'm also trying to start guiding, and have been told this will considerably increase the power consumption of my mount, adding to the problem.

Presently, I'm imaging from my garden, so do have access to mains power.

Have asked Primaluce for a recommendation, and they suggested a heavy duty car battery for powering everything.  Not too keen on having to haul a heavy car battery back & forth in each session however.

Also asked 365Astronomy who sold the camera originally.  They suggested using my Powertank, stating to have used just such one for such a camera.

Figure the cooling must work on the same principle in other cooled cameras, so expect them all to have high power demands, and so wondering; what do you guys with cooled cameras use to power them ?

Thanks in advance for any answers.

 

Regards,

Erling G-P

That is not far away from what most dedicated cameras with larger sensors draw. My ASI1600mm pro is about 12volts at 2 amps for example, its a smaller sensor than the APS-C in that camera. 

You are going to be looking at a deep cycle caravan leisure battery if you want to go over 3-4 hours. Or just multiple power tanks. 

Something like this perhaps.

https://www.amazon.co.uk/SuperBatt-LM110-Leisure-Battery-Motorhome/dp/B00Q8N66B0/ref=asc_df_B00Q8N66B0/?tag=googshopuk-21&linkCode=df0&hvadid=310315668927&hvpos=1o5&hvnetw=g&hvrand=16988168541733981736&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9046228&hvtargid=pla-888864803952&psc=1

Adam

 

[david_taurus83]

I use a Nevada 30 amp linear power supply out to my AZEQ6, ASI1600MM, powered USB hub and 2 dew straps. Even with the mount slewing in both axis the ammeter never goes above 3 amps. I use a 12v car multi cigar socket that I've hardwired to a 3 core 1.5mm cable (I only use 2 core for DC), the yellow ones we use on building sites with the 110v sockets. Cheap enough to buy and they stay flexible when cold. If working with low voltage like 12/13.8v you need to be aware of voltage drop over long cables. The thinner the cable, the more volts you will drop over the length of the cable. My cable is 15m long and theres only maybe a couple of volts dropped when everything is running so I crank the output to 15v.

 

If you want to stick with a battery then an 80ah caravan battery can be had for less than 100 quid. Or the more expensive option is the light and efficient Tracer power packs.

[Erling G-P]

Thanks for the replies.

With a history of several hernia operations behind me, I'm trying to avoid heavy lifts as much as possible, so 20kg batteries would not be a wise solution.  Thus leaning towards something mains connected.  David, is it correctly assumed that you keep your power supply indoors, and then run a long, low voltage cable to your equipment ?

Regards,

Erling G-P

[david_taurus83]

1 hour ago, Erling G-P said:

Thanks for the replies.

With a history of several hernia operations behind me, I'm trying to avoid heavy lifts as much as possible, so 20kg batteries would not be a wise solution.  Thus leaning towards something mains connected.  David, is it correctly assumed that you keep your power supply indoors, and then run a long, low voltage cable to your equipment ?

Regards,

Erling G-P

Yes! Obviously a 30 amp supply is overkill. Nevada do an 8 amp supply and is quite popular. The only reason I went for the bigger version was the concern about voltage drop over the length of cable I use and it has the ability to raise volts to 15.

You would need to decide a way to split the power supply at the mount to the various accessories.

 

https://www.firstlightoptics.com/batteries-powerpacks/nevada-ps-08-6a-8a-regulated-linear-power-supply.html

 

And the version I choose, quite heavy though and quite noisy when the fans kick in.

 

https://www.nevadaradio.co.uk/amateur-radio/amateur-radio-power-supplies/nevada-ps-30m

 

I use something similar to this for distribution. I cut the cigar plug off and hardwired (crimped as I cant solder to save my life!) it to my yellow cable. Also put an in line fuse in.

 

https://www.amazon.co.uk/BESTEK-3-Socket-Cigarette-Lighter-Splitter/dp/B076Q2S7QW

 

Obviously there are neater solutions available specifically for astro gear like the Pegasus Powerbox and Hitech Astro mount hubs etc but they have a heavy Astro-tax applied..

[Erling G-P]

Thanks for the reply and the links David.  The smaller power supply appears fixed at 13.8V, which would make it a no go for me.  I had seen other supplies fixed at this specific voltage, and asked Primalucelab if that would be ok for the cooling, but they warned I might ruin it if I went beyond 12V, so don't dare do this.  Without knowing how much of a voltage drop I might see if I use a long cable, it would be a bit of a gamble.  

Like you say, there seems to be many different ways to do this, so I have some thinking to do. Adding to the complexity, the supplied power cable for the camera has banana plugs in the supply end, and the socket in the cooling unit is incompatible with the kind of power cables I use for my mount & the Synguider - looks like the same kind, but the center pin is a little bit thicker.  Thus I may have to modify the supplied one.

[Adam J]

1 hour ago, Erling G-P said:

Thanks for the reply and the links David.  The smaller power supply appears fixed at 13.8V, which would make it a no go for me.  I had seen other supplies fixed at this specific voltage, and asked Primalucelab if that would be ok for the cooling, but they warned I might ruin it if I went beyond 12V, so don't dare do this.  Without knowing how much of a voltage drop I might see if I use a long cable, it would be a bit of a gamble.  

Like you say, there seems to be many different ways to do this, so I have some thinking to do. Adding to the complexity, the supplied power cable for the camera has banana plugs in the supply end, and the socket in the cooling unit is incompatible with the kind of power cables I use for my mount & the Synguider - looks like the same kind, but the center pin is a little bit thicker.  Thus I may have to modify the supplied one.

What you need is a buck converter with boost at the far end of your cables close to the mount that way the voltage drop won't matter. But to be honest I think you are far better off still placing the power supply in a waterproof box and feeding input and output cables through a rubber grommet. 

Edited November 9, 2019 by Adam J