Single to 3 phase inverters

[9fingers]

I have a varied selection of these inverters on the shelf that I've bought/collected over the years - possibly more than I need if truth be told.
Whilst I'm not actively seeking to sell them, anyone who needs an inverter to run a 3phase machine from a domestic supply might like to contact me. I'm not looking to make a profit from these but ideally cover my costs and see them put to good use.

I have three types:-

230v single phase input - 230v 3phase output (use with dual voltage motors)
415v 3phase in - 415v 3phase output (needed for variable speed applications only)
230v single phase input -415v 3phase output (needed for single voltage three phase motors)

I can offer advice on installation and if needed program the inverter to suit your application.

Bob

MODS: I have deliberately not put this in the for sale section due to it's general nature and lack of price info. Hope this is OK

 

[SammyQ]

Bob, can you keep me in mind for a 240V in/415 out please? I'll contact you via PM later when work allows. Sam

 

[9fingers]

No problem Sam I'll wait to hear from you

Bob

 

[The Bear]

Bob I've sent you a PM

Mark

 

[Bigdanny]

Hi Bob, Im interested in the 415v 3phase in - 415v 3phase output could you send more details. What Kw will it work to. Im looking to control a whitehead bandsaw to slower speed so I can cut metal.
Cheers
Danny

 

[9fingers]

Hi Danny,

Normally, to drop the speed of a woodcutting bandsaw enough to cut metal, a combination of pulley changes and motor speed control is needed. In addition, extra cooling is needed on the motor as the built in cooling fan will be too slow to keep the motor cool.

I would suggest a minimum operating frequency of 10-12Hz which drops the blade speed to 1/4-1/5.
What is the power of your motor? I can then go through my stock and see what I have that might be suitable.

I had a similar requirement to convert my 1hp bandsaw to cut metal - details here

modifications-to-a-startrite-bandsaw-t38613.html

I think you will need to do something similar to get your blade speed down to 100 fpm (30m/m) for metal use.

hth

Bob

:idea: The other way to avoid mechanical work on your saw is to swap the motor for one that runs at half the speed of the original, and then use an inverter running at 100 Hz to get the original top speed and back it off to 12.5 Hz say to get an 1/8 of top speed for metalwork.

 

[Jensmith]

My bandsaw was originally 3 phase and Dad put in a single phase motor. Is it worth considering switching back? No idea what type of inverter it would need.

 

[9fingers]

My bandsaw was originally 3 phase and Dad put in a single phase motor. Is it worth considering switching back? No idea what type of inverter it would need.

To what end Jennifer?
Are you still having problems with tripping on start up? or was that someone else? An inverter is much 'gentler' on the supply at start up compared to a single phase start up for the same power output.
If you want variable speed in order to cut metal and are only cutting thin aluminium or brass then an inverter should get you in the right speed range but if you want to cut steel, then see my reply to Danny above.

If you want to explore further then let me have the details off the rating plate of the 3 phase motor via PM to save the thread getting complicated further by discussing different issues with others

Bob

 

[dickm]

Hi Danny,

Normally, to drop the speed of a woodcutting bandsaw enough to cut metal, a combination of pulley changes and motor speed control is needed. In addition, extra cooling is needed on the motor as the built in cooling fan will be too slow to keep the motor cool.

I would suggest a minimum operating frequency of 10-12Hz which drops the blade speed by 1/4-1/5.
What is the power of your motor? I can then go through my stock and see what I have that might be suitable.

don't like to question the expert :lol: , but surely a frequency of 10-12 hz would drop the speed TO 1/4-ish, not BY 1/4ish?
Or am I being stoopid again? (blame the shingles if I am )

 

[9fingers]

No **** you are quite correct - it's my loose/wrong use of English.

I'll edit my post

Bob

Hope the shingles are soon dispatched!

Bob