AWGB Woodturning Forum

General Category => General Discussion => Topic started by: Wood spinner on October 27, 2023, 02:40:22 PM

Title: Inverter care / maintenance
Post by: Wood spinner on October 27, 2023, 02:40:22 PM
Amyone have any opinions regarding inverter care , My concerns are temperature variations . In winter the temperature can drop as low as -8 , in summer +40  in my workshop , Just wondering if a small heater / heat pad would help stabilise the temperature ,
Why ? I here you ask , Cost of replacing an invertar is not cheap  :o
Title: Re: Inverter care / maintenance
Post by: Paul Hannaby on October 27, 2023, 05:07:43 PM
Probably the biggest risk is condensation due to the cold which could cause corrosion or shorts between conductors so preventing that is where I would target my efforts.

VB36 lathes are renowned for inverter failure due to the inverter being located in the bottom of the headstock, the bottom of which is open and a trap for condensation!

An inverter kept in the right environment could last for decades even if switched on all the time.
Title: Re: Inverter care / maintenance
Post by: Twisted Trees on October 27, 2023, 07:29:07 PM
I wouldn't do it personally but an inverter left switched on will create some heat which is coming from inside to outside and I would think preferable to a heat pad, less likely to bring damp in if it is itself the heat source maybe?

Look to insulation combined with ventilation as passive environment protections of your tools and machinery is the first call for any workshop.
Title: Re: Inverter care / maintenance
Post by: jay on October 27, 2023, 09:54:18 PM
    I find that a small heater  keeps the shop above 7C unless I am working then I set it higher combined with a small dehumidifier that keeps it at 55% very successful. No problems with either lathe both with VFD  or with rust on the polished cast iron table on my spindle molder
Title: Re: Inverter care / maintenance
Post by: Duncan A on October 28, 2023, 11:02:08 AM
The Delta EL manual states -10 to +50C for operation; -20 to +60C for storage; <90% relative humidity for both cases, no condensation allowed.

The Delta S manual states  -10 to +40C for operation; -20 to +60C for storage; <90% relative humidity for both cases, no condensation allowed.
This type of inverter, without a cabinet, is widely fitted to lots of lathes: Jet, Axi, Charnwood to my knowledge. I do know of one on a Charnwood lathe that sat in a wooden shed for several years and then was returned to use without any problems at all - although the internal capacitors really should be powered up annually.

Other brands seem to be fairly similar.

Most likely scenario where condensation occurs would be sitting in a very cold workshop and then warming it up rapidly.

As long as damp is not excessive, I think you'll wimp out before the inverter does!

Duncan
Title: Re: Inverter care / maintenance
Post by: Richard_C on October 29, 2023, 11:34:37 AM
Most likely scenario where condensation occurs would be sitting in a very cold workshop and then warming it up rapidly.

I work in half a double garage.  Last December unusually for here the temperature dropped well below freezing for several days, -10 at times, so (being an amateur) I didn't go out there for long.  The duration of sub zero meant that everything in there got very cold, unlike the more normal cold night/warmer day where the theremal mass of the building itself moderates things.  Then the temperature rose to +11 overnight, next day everything was at best damp but in many cases wet, cast iron lathe bed, bandsaw table etc being the worst.  Inevitable really, I didn't start anything motor powered, left all the doors and windows and cupboards and everything open for several hours over 2 days and and wiped down what I could and all was well.

The post above is right, its not the temperature that is the risk it's the change in temperature.
Title: Re: Inverter care / maintenance
Post by: Wood spinner on October 29, 2023, 03:22:28 PM
OK Thanks for the comments.