SS

Sandingdust

27/03/2007 5:43 AM

Using 230V 1Ph 60Hz Machines in 220/240V Country


Dear All,
I'm sure this question may not be the first time appear in this forum.
However, I am not able to search for similar threads previously posted
by other members of this very useful forum.

My question is : Can I use a Saw Bench (Table Saw) purchased from
America with 230V power input in my country with 220/240V at 50hz
power supply?
Facts: Normally, most machines of 3hp & above, produced for
America's market, use power input of 230V/405V at 60hz cycle or
frequency. Some types of machines with carbon brush (esp. direct
shaft motor) use universal motors ( can use 50hz or 60hz power input).
Most machines powered by "Induction" motors (esp those using drive
belts) are not using universal motors. Is it true ?

I appreciate whatever reply from you all..

Thank you

Sandingdust
KUL, MY




--
Sandingdust


This topic has 2 replies

AD

"Andy Dingley"

in reply to Sandingdust on 27/03/2007 5:43 AM

27/03/2007 4:51 AM

On 27 Mar, 05:43, Sandingdust <[email protected]>
wrote:

> My question is : Can I use a Saw Bench (Table Saw) purchased from
> America with 230V power input in my country with 220/240V at 50hz
> power supply?

Single phase 230V power is compatible, although you're likely to have
to rewire the connectors and switchgear.

If you're bringing it into Europe, you're likely to have to comply
with the PUWER '98 regulations. These impose some very sensible
requirements on guards and switchgear (NVR at least, ideally a proper
starter and isolator. Certainly not one of those crappy US toggle
switches). They also have some requirements on spin-down times, which
sometimes need brakes adding to heavier machines. The UK HSE has a
good website on these things.

There's a theoretical issue over frequency, where the eddy losses are
higher at 50Hz than at 60Hz. This increases the heat dumped into the
motor and for a motor whose output power is limited by heat build-up,
then it'll still work fine, but you have to reduce the overall rating
of it. This is a minor issue in practice. Although modern motors are
"cheaply made" compared to 1950s design (which could equally well be
termed "over-weight") you'll find that Chinese manufacture is designed
for 50Hz anyway. As most hobbyist woodworking machinery runs at an
easy duty cycle anyway, long-term heat build-up isn't as much of a
problem as short-term over-current and simple Ohm losses in the
windings.

LH

Lew Hodgett

in reply to Sandingdust on 27/03/2007 5:43 AM

27/03/2007 11:43 AM

Sandingdust wrote:

>
> My question is : Can I use a Saw Bench (Table Saw) purchased from
> America with 230V power input in my country with 220/240V at 50hz
> power supply?

Not at full power or on a continuous basis, there is simply not enough
iron in 60 HZ motors to operate at 50 HZ for any length of time.

Lew


You’ve reached the end of replies