it can indeed be simple converted. u need a capacitor of course and the power will be limited. just google after steinmetz!
my faema fp grinder has the same modification and ive seen it within a few grinders....so should really be no problem, except for the limited power (but they are overpowered anyway...)

13thfloorelevators wrote:it can indeed be simple converted. u need a capacitor of course and the power will be limited. just google after steinmetz!
my faema fp grinder has the same modification and ive seen it within a few grinders....so should really be no problem, except for the limited power (but they are overpowered anyway...)

What you are apparently advocating is ill advised. It's possible to start a three phase motor on single phase by adding capacitance to two legs and changing the starting capacitor. This is a so called "static phase converter". The additional capacitors, charge and discharge on startup to start the motor. But while relatively inexpensive, this is inefficient, causes the motor to run hot and only at partial power. Not to mention that choosing the correct size capacitors varies with the motor size and is largely trial and error. If your motor is run under full load it may well burn out due to the poor quality power that will create a lot of heat in the motor windings.

On the other hand, the more expensive variable frequency drives or (better quality) rotary phase converters work fine if you can find an affordable one. The best luck is if your motor turns out to be wound (wired) at the factory so that it can also work properly on single phase power. If so, then it's simple and inexpensive to change a few wire connections and run such a motor on single phase power.
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We tested the major at the seller.
Have loaded beans. 20 times start has passed successfully. During the next inclusion the major hasn't wanted to twist a millstone. It didn't have not enough electric capacity for start.
Slightly to release knifes towards increase - it has again earned.
Modernization has crashed.

On the bottom I have found out an inscription:

Rostik_KIEV wrote:On the bottom I have found out an inscription:
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The label is indicating that the motor has 3-phase delta and wye windings. So the motor is expecting either 220 or 380V, 3-phase power. There is nothing on the label that would suggest that a single phase tap is also available.

I didn't really understand the latter half of your post. It sounds like the grinder started 20 times, then wouldn't start again. But it wasn't clear why the grinder wouldn't start the 21st time. It could be overheating or a mechanical issue e.g. burr obstruction, failing motor bearing, etc or even a thermal circuit breaker. If you have doubts as to it's reliability, it's probably better to not buy it.
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Mechanical issue (burr obstruction). If between burrs there were beans - the motor sometimes doesn't have capacity to begin rotation.

Rostik_KIEV wrote:Mechanical issue (burr obstruction). If between burrs there were beans - the motor sometimes doesn't have capacity to begin rotation.

Did the seller have the grinder connected to 3-phase or single phase power? The cheaper "phase converters" only let the motor develop about 2/3 power and the motor will also run hot.
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The seller have the grinder connected to single phase power.

wookie wrote:The cheaper "phase converters" only let the motor develop about 2/3 power and the motor will also run hot

"Device S73 is intended for work of three-phase asynchronous engines as capacity to 1,5 kw (special execution - to 4 kw) in a single-phase network without capacity loss."

Cost of the device 75$.

Rostik_KIEV wrote:The seller have the grinder connected to single phase power.

It sounds like the seller is using a delta static phase converter (just a box with 2 or 3 capacitors in it). So the motor will only be producing about 50% of it's normal power and will run very hot. You will have to decide if the motor still has enough power to run normally. The motor may not be able to start if the bean hopper is full and the beans are putting an initial load on the grinding burrs. I would find that frustrating. And it will get worse after the grinder runs for a while and the motor windings heat up.

I suppose if you find the grinder to be a good deal, then it's probably viable for home use. It remains a very bad idea for commercial use as the motor will run very hot and may well burn out under heavy, full load use.
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why do u think that the motor should run hot?
less power of course (i wrote it too), but why should it run hot?

13thfloorelevators wrote:why do u think that the motor should run hot?

A static phase converter creates a phantom phase that is not consistently 120°. This creates a load imbalance that generates heat. Essentially the phases fight each other a bit because they are not well balanced.

This occurs even if the static converter is optimally sized for the motor. But commonly the converter capacitors are not well matched to the motor size and the phase imbalance is larger. And should the motor be overloaded because it must drive the same load with one-third to one-half less power, an even larger source of heat will be generated from the excessive current flow.

A Google search will provide a lot more details, e.g.,
The starting of a 3-phase induction motor connected to a single-phase supply system
Transient Analysis of A Three Phase Induction Motor with Single Phase Supply
http://www.gwm4-3phase.com/autogen.html
http://www.drivesdirect.co.uk/how_to_choose.htm
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