Ignoramus20157 wrote:

On 2009-07-05, John E wrote:

2. Is it normal for electricians to measure the voltage, and "do something"
about it if it's not correct (if only reporting the problem to the
businessman)?

This is the basic question I'm asking. Is it common and regular practice to
inform the owner of a voltage as high as 245? And to suggest that he have
factory personnel come and look at each machine and examine PS taps and such?
And if he had hired a licensed electrician would the electrician likely had
informed the owner of the voltage difference?


I have 245 volts in my garage. Everything works great.

245 volts is a perfectly normal voltage. It corresponds to 122.5 volts
AC from a regular outlet.

There is no causal relationship, as far as I can tell, between
perfectly normal voltage provided in your shop, and your CNC machine
frying after 3 more weeks.

I have not yet seen a more inane discussion thread.


Dont worry there will be more. Its a great form of mindless intertainment.

Any CNC control or machine that cannot take a 10% overvoltage is a
piece of junk to begin with. Power supply technology in the last 20
years can easily design units that will handle these variations. The
power company likes to hold the voltage on the supply lines as high as
possible to reduce the losses per kw metered and delivered.
I have a number of CNC machines running on 515 volts measured at the
machine internal disconnect and never had a control failure from
overvoltage. Undervoltage is what damages equipment because the
currents run higher for the same work done and the power components get
hotter from the higher current.


John