EAF 5V Doesn't Work in the Cold

aatdalt

Hello, I just swapped my 12V EAF for a 5V (thankfully I still have the good old one). Tonight I heard a bunch of beeping and saw the EAF failing to move. The temperature is reading -17C on the EAF. I saw a prompt to change the firmware to 3.1.9 so I went through that process and it still beeped. I saw there was a newer firmware 3.2.3 so I installed that and no good.

This is a standard Meade refractor focuser holding a 1600 and EFW 8 pos at zenith. I slewed horizontal and it still could not move it. This was never a problem with the 12V model, even down to -31C. Does the 5V version just not work in the cold?

Tech@ZWO

aatdalt I heard a bunch of beeping and saw the EAF failing to move.

Please remove EAF from the telescope focuser and move forward or backwards using ASIStudio, if it beeps and does not move, please resetting the 0 position and the maximum number of steps. You can refer to below manual:

https://astronomy-imaging-camera.com/manuals/EAF_Manual_EN_V2.7.pdf

Tech@ZWO

aatdalt even down to -31C

This is just good luck, our EAF does not use industrial components, which means we can't guarantee each one can still work without any issues under such low temperature, the acceptable range is -5-50C.

aatdalt

@tech@zwo#52304 Yes, I did that and it would just stall and beep. I installed the 12v version back on and it had no trouble.

aatdalt

@tech@zwo#52353 Do you plan to do anything to fix this? -5C is not an unusual temperature to reach by any stretch for a huge portion of the US and around the world.

w7ay

aatdalt -5C is not an unusual temperature to reach by any stretch for a huge portion of the US and around the world.

The number that is quoted to you earlier is also overly optimistic.

Commercial integrated circuits are rated to work between 0ºC and +70ºC. Using them out of that range is like going to Las Vegas.

Industrial grade chips are rated from -40ºC and +85ºC; in a simple product like the EAF would probably raise the cost by $2. Mil grade rating (definitely a step up in price) is between -55ºC and +125ºC.

You really need to read the specs yourself before buying anything. Don't go by the shills on Facebook and YouTube.

Also, try removing your EAF completely from your focuser so the EAF shaft is completely free to move. Then test it at cold temperatures (even your freezer should work). If it moves fine, then check for other things, like a flexible coupler that is not fully straight (EAF shaft and focuser shaft not perfect lined up), nothing is binding the focuser, etc.

Chen

aatdalt

w7ay It would have been nice if ZWO had any published specs before I made the purchase. And if you read my previous comments, I did remove the EAF from the focuser and it could not move itself. I recognize that my own temps are extreme but I also recognize that -5C is not extreme.

craigg

This is a troubling issue. If ZWO is marketing this non-12v EAF to customers around the world while knowing that whatever components contained in the EAF will likely not function for customers that use it in a normal, expected temperature environment, they're being somewhat disingenuous.

To rectify that, ZWO should respond immediately to positively address the concerns by acknowledging the oversight (?), find some way to compensate users that purchased the non-12v EAFs in good faith, and move to solve the problem in future production units even if it comes down to an increase in the price.

That is the way it works at least in our little part of the world.. it's called managing customer expectations.