Hi,

I have been operating an enhanced Ox CNC for the last few months and all has been going smoothly.

I operate a 400W 48v Chinese spindle which performs flawlessly apart from one electrical issue I think I have introduced. I operate it at max rpm via the potentiometer which is stated to be 12000r/min on the datasheet, although I do not currently have a way to measure the rpm. I decided to extend the cabling from the spindle to the speed controller in order to tidy up the cables. This involved an extra metre of same gauge wire to what the manufacturer supplied. Now, when I reconnected and powered up, the rpm seems to be slower based on the sound and additional bit chattering when operating at the same feed rate and depth of cut as before. (3mm depth 1400 mm/min). It feels like a 20% reduction if I had to make a guesstimate.

My question is, as I have extended the cabling, has this introduced a voltage drop due to increased resistance over the length and thus caused a reduced rpm? And secondly, what can I do to regain the previous max rpm? Would changing select cables out to a thicker wire help reduce voltage drop?

I extended the following wires,
Motor U, V, W
Hall Sensor Hall+, Hall-,HA, HB, HC

Many thanks in advance for any assistance,

Mike