Potentiometers for Feed/Speed Override UC300-ETH

**PaulP** · 27-09-2020

I'm about to hook up my UC300ETH to an IDC16 breakout board to gain access to the analog inputs. My intention is to use PWM from the UCBB to the VFD to control my spindle's rpms but to have an override potentiometer on the analog pins on the IDC16 port.

On page 19 on the UC300ETH manual it says "The board also has an IDC16 analog I/O port with 2 analog inputs and 2 analog 0-10V outputs" yet on page 21 it doesn't mention the 10v, it only mentions 12v outputs, ground and the analog inputs and outputs. I'm assuming the analog inputs and outputs are running at 10v, am I correct?

As I'm ordering extra bits for this control box I'm after ordering a set of potentiometers to adjust both feeds and spindle rpms yet I'm not sure what resistance the potentiometers should be. Should they be 1K, 5K, 10K or does it not matter? Which pins do I connect each potentiometer up to?

Any help would be greatly appreciated.

**routercnc** · 27-09-2020

I think any of the potentiometers you mention would work as you are just dividing the voltage but I would go for 10k as it passes less current.

**routercnc** · 28-09-2020

I just downloaded and skim read the manual and agreed it is a bit contradictory. Also 90% of it is setting up the Ethernet !

I’m sure you need the analogue inputs port so I would power the board up with the 5V supply then check the voltage of the ports with “12V” coming out. If it really is 12V then I’m not sure what steps are required to get this to represent the full speed range as I’ve only ever gone direct to the inverter.

In any case one end of the pot would go to “12V” the other end to 0V and the centre terminal to one of the analogue inputs. All of these are on the analogue port.

Somewhere I guess you configure the centre terminal input pin to be the speed signal in software but have never used uc300eth so hopefully someone can help confirm.