I've just bought my very first CNC machine with all my hard saved coin. Its an ARROW 500 with CT control. I've been very excited over the past couple of weeks awaiting its arrival. It finally arrived in good shape, so I moved it out of the container and have it in workshop sitting on some blocks of wood. Thought I'd fire her up last night. SO I wired it up - checked the tap connections on the transformer etc. And switched her on. It all seemed to go pretty swimmingly. Booted up, I aligned the axis, then jogged all three. After that I started the spindle, first 500rpm, then ramped it up to 6000rpm, then down to 60rpm and then CCW at 60. All seemed to go well, tho a little noisy. The machine was empty of any toolholders.

I shut the machine down and restarted with the intent of re-aligning and getting the toolchanger figured out. However I smelt a slightly acrid smell, and when I turned the machine on, spindle drive fault came up on screen.

Opening the back cabinet resulted in more of that burning PCB smell. With power on I noticed there was no light coming from the spindle drive board. Took the SA1100 drive out and pulled apart, found what looks to be a little sot23 diode has exploded, also a couple of internal tracks look like they have shat themselves.

I'm really disappointed by this as have spent most the money I have saved hoping I'd be able to make a start NC machining - but now it looks like I'm going to have to spend a ton more getting the thing running.

Any idea what the Spindle motor winding resistance should be? Anything else I should look into? Does anyone have or know of an SA1100 drive going cheap?

How could the drive have blown up without really doing any work?

Any thoughts/help would be really appreciated.

Thx