1ph or 3ph dilemna

Precious Plastic Machine Development
#1

Hi Guys,

Whilst looking into the shredder, i’ve run into a dilemna that prob effects the people this whole concept is aimed at. The ‘small man’ doesn’t normally have a 3ph supply.

A 1ph to 3ph Variable Frequency Drive solves this issue i know, but i think will pretty much double the price of the machine.

Does anyone know of a cheap 2kw 1ph motor? I saw someone on youtube using windscreen wiper motors that couldn’t handle the load and ended up being changed to 3ph. I quite like this idea because you can get them from any scrapyard in the world and they’re easy enough to electrically control, i think. Any ideas?

#2

Hi @paulfreed first of i’ve moved your topic into the machine-development area.

I see your point. Basically any slow powerful engine can be used, if you have other ways to achieve this go for it (and let us know) windscreen experiment sounds interesting, love those little motors!

#3

@paulfreed I put some of my thoughts regarding motors 1ph or 3ph over here
there is a lot of advantages with 3ph motors, apparently there less troublesome, however most of us as you mentioned don’t have access to 3ph, yes it can be done at home if you want to go down that path or that all thats available to you, but I think from most people picking up a 1ph motor maybe the easiest option, is my think at present.

#4

Hey Cyrille!

Thats my biggest issue too. Its difficult to find a cost effective motor and gear.

The down side of the link you posted is that you need two motors.

There is a way to start the motor with capacitors. I haven’t tried it yet myself and I’m not so sure if its the right solution, but see the following…

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#5

I’m having a lot of trouble finding a cheap motor with the right specifications as well! Finding a cheap single phase 2 kW motor seems very hard, but I’ve found this website where they explain how to make a triple phase motor work on a single phase power supply:

http://www.theautomationstore.com/3-phase-electrical-power-from-single-phase/

Did anyone do some tests with lower power motors? Is around 2 kW really the minimum amount of power necessary to effectively shred the plastic?
I’ve found a single phase, 2kW motor with 45 rpm but it costs almost 500 euros…