Single phase to three phase transformer

Thread Starter


Joined Feb 10, 2016

I have a hydraulic clicker press that runs on three phase. The workshop i have has single phase. What kind of transformer do i need to use for this piece of machinery? The motor is 1.5 horsepower and runs at 1430 rpm.
I'm trying to find the cheapest way of doing this!



Joined Jul 18, 2013
A VFD for the 3ph motor, Huanyang are the cheapest but not the ideal quality, Hitachi are a reliable second for a little more cost.


Joined Nov 4, 2013
The best down and dirty design I know of that also lets you have full rated power of your three phase motor while on single phase is this. It's been close to 20 years now since I designed and refined it and I have built too many to count now. Most still running on original parts too! :cool:

For a 1.5 HP hydraulic pump motor you would only need two ~15 uF run capacitors, a 100 - 150 uf start capacitor and a voltage sensing relay. All common items you can get at most any HVAC shop or online.


Joined Jan 17, 2007
I spent way more time than I should trying to decipher their twisted version of Modbus control that it also has.
I've been intending to learn (or use) modbus for a long time. But the truth is I see no reason to discard a standard uart network (be it rs232/485/422) if it is installed correctly and its protocol well and robustly programmed between devices.


Joined Jul 18, 2013
It was not the transmission medium but the S/W coding protocol, a form of Modbus.
The system can be set for RTU (2x4bit hex) or ASCII.
Actually I used RS232 from a PIC with a $3 convertor to RS485 to communicate with the VFD, you can use whatever you want for Modbus.