Emco pc mill 55 upgrade

[EddyCurrent]

Wish i understood the terminology lol but ill get there, took a pic of motor plate for you if it helps, where about are you located ?

Here's some vfd's as example; https://www.inverterdrive.com/group/...r=Power|0.37kW

The max revs shows 1370 RPM so as not to take it past it's working range that should be about the maximum speed to run it at and that's at 50Hz.
The problem is that reducing the speed will also reduce the power so there's a limit to how slow it will usefully operate at.

The vfd needs to be like this;

Input 230V ac single phase
Output 230V ac 3 phase
Power 0.37 kW (minimum)

where about are you located ?

About 200 miles North of you.

[gavztheouch]

Op your are trying to reinvent the wheel here. This conversion has been done lots of times on other forums, there are videos on YouTube and there is also a yahoo group. I would start by hunting down all the various build logs and find out which parts will work for you in terms of vfd's

[magicniner]

The limiting factors for safe maximum speed for an induction motor are the bearings, rotor integrity and rotor balance.
A modern induction motor plate is generally marked with the speeds at 50hz & 60hz, these are neither minimums or maximums, the marked speeds on a motor plate are simply those at which the motor will run for the stated supply frequencies.
Only by referring to the manufacturer's technical specification for a given motor model and power can you determine the maximum safe working speed, inverter rated motors will have the maximum speed stated as a percentage of those marked on the motor plate in the manufacturer's documentation, but not on the motor plate unless expressly stated as a "Max".
I have made use of motor manufacturer data to set the maximum speed for my lathe and mills, all were rated in the manufacturer's documentation at considerably more than 100% of the plated speeds.

- Nick