"Jon Anderson" wrote in message
...
Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Thanks,

Jon

On Jul 15, 11:18*am, Jon Anderson wrote:
Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Thanks,

Jon

First, they have 240 Volts and often a little higher.

Second, for 50 Hz you need to derate by 20% so if the welder will take
120 V / 60 cycles you need to run it on 100 V / 50 Hz otherwise you
will smoke the transformer. Been there, done that. Now if the duty
cycle on the welder is very low you might get away with 120 V OK.

So it comes down to availability of a step down and $$$$. See if you
can order a 50 cycle transformer with taps at 100/110/120.

HIH.

Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Thanks,

Jon

Sorry, I mean to write: Jon it oughta be OK. The spots will just be 5/6th of normal size.

Bob Swinney
"Robert Swinney" wrote in message
...

"Jon Anderson" wrote in message
...
Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Thanks,

Jon

"Robert Swinney" wrote: Sorry, I mean to write: Jon it oughta be OK. The
spots will just be 5/6th of normal size.
^^^^^^^^^^^^^^^^^^^
No, I think you need to consider the *area,* not the diameter. The spots
will be 25/36 the normal size. G

Robert Swinney wrote:

Jon it oughta be OK. The spots will just be 5/6th of normal size.

Thanks, seemed to me it should work, but my knowledge of electrical
and electronics is well within the 'dangerous' range...


Jon

Robert wrote:
Jon it oughta be OK. The spots will just be 5/6th of normal size.
Jon wrote: Thanks, seemed to me it should work, but my knowledge of
electrical
and electronics is well within the 'dangerous' range...
^^^^^^^^^^^^^^^^^^^
Leo writes: Jon, I'm pretty sure he was kidding. But, if you intend to
take him sriously, then see my post regarding diameter vs. area.

Leo Lichtman wrote:

Leo writes: Jon, I'm pretty sure he was kidding. But, if you intend to
take him sriously, then see my post regarding diameter vs. area.

I wasn't sure, but really, I think spot size has more to do with the
diameter of the tips and to a lesser extent, length of weld time.
I just wanted to make sure the welder wouldn't go up in smoke if I tried
to weld something...

Thanks,

Jon

On Wed, 15 Jul 2009 13:08:30 -0800, Jon Anderson wrote:
Leo Lichtman wrote:

Leo writes: Jon, I'm pretty sure he was kidding. But, if you intend to
take him sriously, then see my post regarding diameter vs. area.

I wasn't sure, but really, I think spot size has more to do with the
diameter of the tips and to a lesser extent, length of weld time.
I just wanted to make sure the welder wouldn't go up in smoke if I tried
to weld something...

It probably won't go up in smoke right out of the chute, but I'd keep
an eye on it (or, more accurately, a hand) and if it feels like it's
getting too hot, then cut your duty cycle down to 5/6 of what you did
at 60 Hz.

60 Hz transformers draw more idling current at 50 Hz, and have less
amp-hour capacity than at 60.

Have Fun!
Rich

Rich Grise wrote:
... 60 Hz transformers draw more idling current at 50 Hz, ...

"idling current"? The spot welders that I'm familiar with only energize
the primary when actually welding. I.e., there is no idling current.

Bob

On Wed, 15 Jul 2009 10:18:23 -0800, the infamous Jon Anderson
scrawled the following:

Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Nope, it won't work.

P.S: Save it for me when I come down next week, eh? mwahahahahaha

--
Mistrust the man who finds everything good, the man who finds everything
evil, and still more the man who is indifferent to everything.
-- Johann K. Lavater

"Larry Jaques" wrote in message
...
On Wed, 15 Jul 2009 10:18:23 -0800, the infamous Jon Anderson
scrawled the following:

Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Nope, it won't work.

Please Explain why it won't work.

--
John G.

On Thu, 16 Jul 2009 19:55:17 +1000, the infamous "John G."
scrawled the following:


"Larry Jaques" wrote in message
.. .
On Wed, 15 Jul 2009 10:18:23 -0800, the infamous Jon Anderson
scrawled the following:

Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Nope, it won't work.

Please Explain why it won't work.

You snipped the reason from my tongue-in-cheek reply. I wanted him to
give it to _me_. g

--
Mistrust the man who finds everything good, the man who finds everything
evil, and still more the man who is indifferent to everything.
-- Johann K. Lavater

On Jul 16, 10:55*am, "John G." wrote:

Please Explain why it won't work.

--
John G.

It may not work. Transformers are designed with a ET value. That is
the input voltage times the time is what determines the max flux
density. With 50 hz the time of one half cycle is more than the time
of a 60 hz half cycle. So a transformer used at the same input
voltage will reach a higher flux density on 50 hz power than on 60 hz
power. And depending on the design it may start to saturate the
core.


Dan

On Wed, 15 Jul 2009 12:57:59 -0700, "Leo Lichtman"
wrote:


"Robert Swinney" wrote: Sorry, I mean to write: Jon it oughta be OK. The
spots will just be 5/6th of normal size.
^^^^^^^^^^^^^^^^^^^
No, I think you need to consider the *area,* not the diameter. The spots
will be 25/36 the normal size. G



I think we should plug in a few numbers.

The operating frequency changes from 60 hz to 50Hz but not the
supply voltage

The transformer ratio and hence the open circuit output
voltage is unchanged.

The copper loss is almost unchanged unless the iron circuit
aproaches saturation.

If the transformer is conservatively designed the working flux
density will still be well below saturation flux density. Iron
losses are non-linear but increase by very roughly as the inverse
square of the frequency change i.e. 60/50 squared about 1.4x
Typically the iron losses are about half the total transformer
losses so this is equivalent to about 20% increase in temperature
rise or, for intermittent use, 20% decrease in duty cycle.

If it's light weight low cost design running as close to
saturation as they dare then there will be a larger increase in
iron loss. The welder will still work but you may have to
severely limit the duty cycle to keep the temperature rise within
limits.

Summing up, your welder should work fine on 50Hz.
It is delivering the same output voltage so the spot size will be
unchanged. The transformer will run hotter so you should be
conservative with your duty cycle.

If you are in any doubt about the 50 Hz temperature rise,
you can play safe by reducing the supply voltage. 5/6 approx 100V
would restore the 60Hz flux density but this gives a 20% drop in
output voltage.

Heat output is proportional to V squared so this is equivalent
to a 44% downsizing of the welder capability with proportionate
effects on spot area and permissible sheet thickness.

Jim

On Wed, 15 Jul 2009 21:57:17 -0400, Bob Engelhardt wrote:
Rich Grise wrote:
... 60 Hz transformers draw more idling current at 50 Hz, ...

"idling current"? The spot welders that I'm familiar with only energize
the primary when actually welding. I.e., there is no idling current.

Good point. But, there's still a difference, albeit probably not
enough to blow up the spotwelder. And, as was mentioned, the tranny
would have had to have been right on the hairy edge for 50 Hz to
"blow it up."

Thanks!
Rich

On Jul 15, 2:18*pm, Jon Anderson wrote:
Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

If the transformer takes 110 at 60 Hz, it's safe up to 50/60*110V
at 50 Hz (i.e. 92 VAC). There's also a timer in some spotwelders,
and that might time differently with 50 Hz. Look at the manual
that came with the spot welder, there might be instructions for
connecting different taps on the transformer...

A handheld spot welder's on-cycle is very short, often in mS for thin
materials, and only about 1.5S for 1/8" total thickness. The thickness limit
of most 120V units that I've looked at was about 1/8" total.

The xfmr primary current demand is fairly high (maybe 30A at 120VAC), but
also relatively brief in duration.

If you happen to locate a good deal on 240VAC spot welder in the meantime,
buy it and sell the 110/120V version.
If the Dayton unit is labeled with 110V as the input voltage, it's probably
a fairly old unit or I'm guessing that it was manufactured in Japan/Asia or
the Mediterranean regions to be labeled with 110V.

The issue of destroying the xfmr because of the 50Hz line frequency is
probably of no significance, and a spot welder of decent quality will very
likely have a thermal protection device (self-resetting) inside the xfmr, to
prevent the xfmr from damage due to overheating.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Jon Anderson" wrote in message
...
Pondering selling my Dayton hand held spot welder vs taking to Australia.
Assuming I have a transformer to knock 220 down to 110 that will handle
the current, will 50Hz adversely affect performance? Is there anything
about that which would require uprating a transformer a bit?

Thanks,

Jon

wrote:

Summing up, your welder should work fine on 50Hz.
It is delivering the same output voltage so the spot size will be
unchanged. The transformer will run hotter so you should be
conservative with your duty cycle.

Thank you for the in depth answer! I am looking to take as much tools
and such as possible. It's possible I'd have the only spot welder for
quite some distance, so it's worth taking if it'll work. If it doesn't
work, it'd be worthless there, and cost more to ship back than it's
worth... Sounds like it's worth taking. It seldom gets used, and only
light duty cycles, should be ok.

Jon

John G. wrote:
"Larry Jaques" wrote in message
Nope, it won't work.

Please Explain why it won't work.


That is a commonly understood joke among regulars here. Someone wants to
know the value of something of obvious value, and someone almost always
pipes up and says it's not worth anything but they're willing to pick it
up at no charge. There are several variations.


Jon

On Thu, 16 Jul 2009 12:50:29 -0800, Jon Anderson
wrote:


Thank you for the in depth answer! I am looking to take as much tools
and such as possible. It's possible I'd have the only spot welder for
quite some distance, so it's worth taking if it'll work. If it doesn't
work, it'd be worthless there, and cost more to ship back than it's
worth... Sounds like it's worth taking. It seldom gets used, and only
light duty cycles, should be ok.

Where in Oz are you moving to ? I am in the best part,
the West, unlike poor Andrew who is a resident of Mexico.

I have an ancient hand held spot welder which I usually use to join
galvanised stud, very few of my welds have come apart except when
clobbered with a cold chisel.

It is probably worth bringing even though you will need a step down
transformer. This will give you an idea of prices here
http://www.bobthewelder.com.au/produ...4&cat=6&page=1

Alan VK6YAB

wrote:

Where in Oz are you moving to ? I am in the best part,
the West, unlike poor Andrew who is a resident of Mexico.

Cootamundra, NSW. Very nice little town, sorta reminds me of my home
town in the early 60's in terms of appearance. As in, before new
construction had to fit some urban planner's 'vision' of the
neighborhood and whole blocks were subject to remodeling for the same
reason.

At this point I'm planning on choosing a job (have several folks
interested in hiring me) and spending time getting known before I decide
if I want to open a real commercial business there. If not, I'll just
have one hell of a nice hobby shop. Maybe build a steam locomotive to
run on the tracks in Wagga...
I'm going back end of September and a big part of that will be talking
to some of these folks. My wife, bless her heart, thinks I can do
-anything-. I need to make sure I haven't been oversold....
However, that'll be on hold for some time if I land a job here that I'm
really hoping for.

This will give you an idea of prices here
http://www.bobthewelder.com.au/produ...4&cat=6&page=1

Uh, yeah, I'd say it's worth bringing mine for sure! That's a much nicer
spot welder than mine, but for my infrequent needs, that unit would be
overkill...

Jon

wrote:
On Thu, 16 Jul 2009 12:50:29 -0800, Jon Anderson
wrote:


Thank you for the in depth answer! I am looking to take as much tools
and such as possible. It's possible I'd have the only spot welder for
quite some distance, so it's worth taking if it'll work. If it doesn't
work, it'd be worthless there, and cost more to ship back than it's
worth... Sounds like it's worth taking. It seldom gets used, and only
light duty cycles, should be ok.


Where in Oz are you moving to ? I am in the best part,
the West, unlike poor Andrew who is a resident of Mexico.

I have an ancient hand held spot welder which I usually use to join
galvanised stud, very few of my welds have come apart except when
clobbered with a cold chisel.

It is probably worth bringing even though you will need a step down
transformer. This will give you an idea of prices here
http://www.bobthewelder.com.au/produ...4&cat=6&page=1

Alan VK6YAB


*"Maximum Plate Thicknesses 2mm + 2mm @ 60 Spots per second."
60 spots per second would be good going for a robot, that's a hand held
spot welder. What are they expecting a spot per cycle and it's a 50Hz
location.

*I've got virtually the same welder and someone might want to point out
to them
their error, I can't be bothered as they have a form to fill in for
email. The capacity is 60 spots per hour at 2mm + 2mm.