Is it bad to leave your Asiair Plus on for a couple days at a time?

thebruce

Hi all - relatively new to the AA+. As the weather is getting better in SF Ive been covering my scope in the morning but leaving the AA+ on all day so I dont have to re-polar align at night. Is this bad for the device, any best practices here?

Thanks!

w7ay

thebruce Is this bad for the device, any best practices here?

I assume that you mean with the unit powered on?

With no power applied, you should be able to do it indefinitely with zero problem (I have my power distribution and various processors, including the ASIAIR, sitting inside a water-proof ABS box at the base of my Mortar tri-pier semi-permanently outside in the sun, rain and snow 24x7 for a few years now. The RST-135 is also outside on the tri-pier, under two layers of dry bags (just in case one leaks during the Pacific Northwest rain storms). If your mount uses grease, I would be more concerned about leaving it out in the sun than with an ASIAIR.

Cover with an extra "emergency mylar thermal blanket" to keep your covering cooler if you are concerned. Going price at Amazon seems to be about $2 a piece (for a peace of mind -- sorry, dad joke).

I also have a first generation ASIAIR (Raspberry Pi 3 based) powered on 24x7 as an all-sky camera. I do have it out of the original Raspberry Pi enclosure inside an ABS box that also holds the camera and the acrylic dome (which lets in a lot of heat in the daytime). A caveat is I am in Portland OR, and the Sun never gets as high as SF (used to live in Sunnyvale; escaped and never looked back :-).

Now, there are two versions of "ASIAIR Plus" (depending on when you bought it). The third generation ASIAIR uses the Raspberry Pi CM4, and the newer fourth generation, but with the same model name (can you say switcheroo?) uses the RockChip. The thermal tolerance could be different between those two.

Anyhow, not powered on: zero problem unless you are in the Mojave. Powered-on: check the processor temperature in the ASIAIR Settings page. If it gets close to 80ºC, power it off. I wouldn't run it under the sun in Phoenix in the summer without a thermal blanket, for example.

But as I said, no problem with my all-sky camera powered on all the time. This is what the processor temperature looks like at the moment (air temperature about 40ºF):

Chen

thebruce

Thanks so much! A thorough reply as usual 🙂 Yea Ive just been leaving out for a few days at a time in SF while powered on so save me the hassle of re-polar aligning. I cover it in the morning and then it's ready to go in the evening. Temps here are never really too hot or too cold.

Another question on the camera and cooler. Do you turn the camera or cooler off when not using?

w7ay

thebruce Ive just been leaving out for a few days at a time in SF while powered on so save me the hassle of re-polar aligning.

Ah, you should be able to turn off power in the daytime. (Unless you are doing Solar Hα work, that is.)

Polar alignment is purely a mechanical adjustment. It ensures that the polar axis of the mount point close to the actual north celestial pole (NCP). As long as the mount does not move between one night and the next, you do not need to re-do polar alignment, whether the ASIAIR is turned on or not.

You do need to make sure that your dog or cat (or a deer or racoon) does not brush against the tripod legs since we are talking about arc minutes to arc seconds type precision. One end of a moment arm of 1 meter (e.g, spread of a tripod leg separation) only needs to move 0.3 mm up or down to produce an arc minute of change.

So, even if the ground under one tripod leg settles by only 0.2 mm, you would normally want to re-polar align. But in this case, you need to re-align even if the ASIAIR had been powered on, anyway.

The ASIAIR power has nothing to do with polar alignment; in fact you can polar align using a PoleMaster or with SharpCap, and proceed to use ASIAIR without going through the ASIAIR polar alignment process.

Temps here are never really too hot or too cold.

Yeah, but you have that pesky Marine layer :-).

Another question on the camera and cooler. Do you turn the camera or cooler off when not using?

I turn mine off until I need it for imaging, just because fans have limited time before they fail. And I really don't want them to fail while the Peltier cooler is running. Something will melt with 36 watts of power going in, and no fan to extract the heat. I don't think ZWO cameras come with a fail-safe mechanism to turn off power to the Peltier device if the fan ever stops.

Plus, cameras like the ASI2600 have a penchant to leak thermal greese; you don't want to stress the Peltier cooler. Even at times that I do have the cooler on, I would monitor the cooler power so that it does not go above 85% to 90%. On warm Summer evenings when the cooler is more stressed, I would back off and live with a higher sensor temperature (need different set of dark frames, of course). So far, I have been lucky that there is no grease leaks on my two ASI2600 (a color and a monochrome) but I don't know how long my luck will hold. It is something you might consider -- it just depends on how much risk you are willing to tolerate.

Chen