380 Volt, 50hz.

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controlled

Senior Member
I am a Canadian EC, installing a machine that is coming from Europe. The machine nameplate shows the electrical specs as 380V, 40A, 3 phase, 50hz.

The Canadian standard industrial voltage is 600V. The manufacturer said to install a 45KVA, 600/480 transformer. How can this be correct is the machine is designed to run in 380V 50hz????
 

xformer

Senior Member
Location
Dallas, Tx
Occupation
Master Electrician
I am a Canadian EC, installing a machine that is coming from Europe. The machine nameplate shows the electrical specs as 380V, 40A, 3 phase, 50hz.

The Canadian standard industrial voltage is 600V. The manufacturer said to install a 45KVA, 600/480 transformer. How can this be correct is the machine is designed to run in 380V 50hz????

sounds like you might need to in stall a buck/boost transformer also....
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Won't change the frequency.

Which means that you really need to know whether the motor speed is critical to the operation of the machine. Using a 60 Hz motor or control transformer on 50 Hz can cause overheating. The reverse is generally just fine except for motor speed concerns.

If exact speed is important in the operation of the machine, a properly specced VFD would be the better solution.
 

templdl

Senior Member
Location
Wisconsin
Won't change the frequency.

Mega dittos. This is a most important issue. There are many ways to deal with voltage but frequency is a another issue though 50hz transformers quite often will work fine on 60hz but 60hz transformers on 50hz is not a good thing as they will overheat.'
 

augie47

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Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
agree... that, I believe, was discussed in the thread I linked.
Assuming motor speed is not a critical issue, if he is going to be operating on a 60Hz system would he be better off with a 480v secondary or a 400v secondary ?
 
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I am a Canadian EC, installing a machine that is coming from Europe. The machine nameplate shows the electrical specs as 380V, 40A, 3 phase, 50hz.

The Canadian standard industrial voltage is 600V. The manufacturer said to install a 45KVA, 600/480 transformer. How can this be correct is the machine is designed to run in 380V 50hz????

Send it back and have them built one for the market. I am getting sick and tired of 'us' needing to comply with whatever $#^% they wish to sell us.....Think about replacement/spare parts, performance discrepancies - for which they goig to blame the user not using proper voltage - and additional repair cost that an unfamiliar system creates.
 

Besoeker

Senior Member
Location
UK
Send it back and have them built one for the market. I am getting sick and tired of 'us' needing to comply with whatever $#^% they wish to sell us.....Think about replacement/spare parts, performance discrepancies - for which they goig to blame the user not using proper voltage - and additional repair cost that an unfamiliar system creates.
Whilst, to some extent, I can understand the disgruntled tone of your post, nobody required the buyer to buy unsuitable kit. As far as I can tell.

Perhaps it was an error by the supplier in not knowing where the end user was or by the buyer not being aware that, in sourcing the equipment from overseas that there might be differences in supply voltage requirements.
Whatever, no one is forcing you to comply with non-US supplies.

Just be thankful that you don't have the harmonisation stuff (or other substitute word) that we've had forced upon us.
 

mike_kilroy

Senior Member
Location
United States
so "machine" was built to run on 380v 50hz. u have 600v 60hz. mfgr says use xfmr to provide 480v 60hz.....

If the "machine" has nothing but ac induction motors & solenoids on it, then mfgr is CORRECT.

If the "machine" has more stuff than just induction motors and 50hz relays, then mfgr MAY be wrong.

What is your "machine?"

FYI, 380v@50hz into induction motors makes it just as happy as 460v@60hz into it - keep in mind it will go 6/5 faster too....
 

hurk27

Senior Member
The V/f may be right.
The power might not.

Wouldn't that depend upon the type of load the motors are driving?, constant torque applications are the worst as driving a pump or blower/fan at a higher frequency will increase the load on the motor and if of a direct drive design you would have problems with slowing it back down without using a VFD or changing the blade pitch, while the voltage/frequency ratio is in line for motors, the higher rpms can be a problem depending upon what the motors drive?

While many industrial electronics today are mostly being fed with power supplies of a switch mode design that accept a wide voltage/frequency range input and are not as big of a problem as they once used to be, we have some at work that will go from AC or DC 100 volts to 300 volts and still output the 24 volts they were designed to, we have these also with 12 or 10 volt outputs also.

So the manufacture could be correct since they should know their machine that it will operate just fine on 480v/60hz, just make sure you document that doing this was the result of the equipment manufacture and save any hard copies of any thing that you get to fall back on if things do go wrong, I would ask the manufacture to send you instructions for any changes you may have to make to run the equipment on 480 volts and 60hz, this way at least you have a paper trail that the manufacture was aware of it.
 

Besoeker

Senior Member
Location
UK
Wouldn't that depend upon the type of load the motors are driving?, constant torque applications are the worst as driving a pump or blower/fan at a higher frequency will increase the load on the motor and if of a direct drive design you would have problems with slowing it back down without using a VFD or changing the blade pitch, while the voltage/frequency ratio is in line for motors, the higher rpms can be a problem depending upon what the motors drive?
For a centrifugal fan or pump, the load is proportional to rpm3.

So, running at 60Hz instead of 50Hz would increase the load by about 70%. Assuming the efficiency stays the same, motor losses would have a similar increase. Bad news for the motor if it was designed to run at rated load at 50Hz. Much electrical equipment, conductors, transformers, motors, is sized to dissipate losses at design rating. Exceeding that by 70% would be bad news.

In this particular case, we have no information on what the motors are doing. A constant torque load might be OK. The losses would still go up but not by as much. How much design margin was there built in? And, in my experience, there are few loads that are really constant torque.

While many industrial electronics today are mostly being fed with power supplies of a switch mode design that accept a wide voltage/frequency range input and are not as big of a problem as they once used to be, we have some at work that will go from AC or DC 100 volts to 300 volts and still output the 24 volts they were designed to,
Agreed. And not just industrial. The wall-wart for my phone, PC, printer etc. will work anywhere in the world.

So the manufacture could be correct since they should know their machine that it will operate just fine on 480v/60hz, just make sure you document that doing this was the result of the equipment manufacture and save any hard copies of any thing that you get to fall back on if things do go wrong, I would ask the manufacture to send you instructions for any changes you may have to make to run the equipment on 480 volts and 60hz, this way at least you have a paper trail that the manufacture was aware of it.

Agree. Sound advice for all projects.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
There is a lot of stuff coming in from Japan and Europe that is perfectly good machinery but is not made for either the US or Canadian markets but can be readily adapted to it.

It would not surprise me any to find that it is not the first time the manufacturer has sold something to Canada or the US.

A lot of motors made for the EU market 380V/50Hz also have specs from the motor manufacturer for running at 480V/60Hz. Take a look at the nameplate on the motors. Sometimes the dual rating is on the motor and sometimes you have to look up the motor datasheet.
 

Besoeker

Senior Member
Location
UK
A lot of motors made for the EU market 380V/50Hz also have specs from the motor manufacturer for running at 480V/60Hz. Take a look at the nameplate on the motors. Sometimes the dual rating is on the motor and sometimes you have to look up the motor datasheet.
Agreed.
As I noted earlier, the V/f will be right for the motor and no doubt it can run on that perfectly well.

But it isn't just about the motor.
The load has to be considered
Is it OK to run it at 60Hz speed?
Is the motor rated to run it at 60Hz speed?
Unless the torque reduces with increasing shaft speed (unlikely), the power requirement will increase for the faster speed. P=Tω. At least.
Can the motor handle the extra power?

Just a few things that need to be considered with a bought in piece of kit.

And, just a point of information.The EU nominal 3-phase voltage is 400V. Yet another "harmonisation" fudge. UK was 415V/240V. Continental Europe was largely 380V/220V.
We are all now 400V/230V.
Not that anything much changed. Just the tolerances were made greater to accommodate this wonderful political expediency.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
Agreed.
As I noted earlier, the V/f will be right for the motor and no doubt it can run on that perfectly well.

But it isn't just about the motor.
The load has to be considered
Is it OK to run it at 60Hz speed?
Is the motor rated to run it at 60Hz speed?
Unless the torque reduces with increasing shaft speed (unlikely), the power requirement will increase for the faster speed. P=Tω. At least.
Can the motor handle the extra power?

Just a few things that need to be considered with a bought in piece of kit.

And, just a point of information.The EU nominal 3-phase voltage is 400V. Yet another "harmonisation" fudge. UK was 415V/240V. Continental Europe was largely 380V/220V.
We are all now 400V/230V.
Not that anything much changed. Just the tolerances were made greater to accommodate this wonderful political expediency.

Like I said, it is probably not the manufacturer's first experience sending this kind of stuff overseas. There are all kinds of things that might be, but chances are it will work just fine.

In any case, it is not the electricians job to worry all that much about whether the motors will have enough torque. That is well beyond installing it electrically. Someone spec'd this machine out and was responsible for making sure the manufacturer got the right information on which to design the machine.

Document what you did and why and don't worry all that much about it. It is no different than any other machine that you are relying on the manufacturer to design it correctly and your own internal people to spec it right.
 
Whilst, to some extent, I can understand the disgruntled tone of your post, nobody required the buyer to buy unsuitable kit. As far as I can tell.

Perhaps it was an error by the supplier in not knowing where the end user was or by the buyer not being aware that, in sourcing the equipment from overseas that there might be differences in supply voltage requirements.
Whatever, no one is forcing you to comply with non-US supplies.

Just be thankful that you don't have the harmonisation stuff (or other substitute word) that we've had forced upon us.

Obviously the buyer made an uninformed decision. The Seller should have warned, but I think they were happy to pass on the burden. Dishonest marketing is what I call it.
 

Besoeker

Senior Member
Location
UK
Peter and Lasszlo

Somewhat conflicting points of view there.
A few thoughts in no particular order.

Lasszlo
If the buyer made an uninformed decision, and we don't know that for sure but it seems likely given that the EC had to ask the question, then one might wonder whether the buyer is the right person for that position.
It is not known if the seller was aware that the end user was in a different country with a different supply system. If he was, then yes, I agree that the differences should have been pointed out. But suggesting that the seller dishonest without better information seems just a wee bit harsh.

Peter
You are suggesting that the kit might just work. And it just might. Motors, maybe if the driven load....well see my previous post. And I seem to recall that the OP mentioned heaters. About 20% higher voltage would make me question that.
But I agree that it isn't for the electrician to be concerned about that. I don't know the status of the electrical contractor. If nothing else, he had the nounce to question the disparity between nameplate voltage and frequency and his supply. And you're right. A written confirmation from the manufacturer of what needs to be done to match equipment specification to supply would resolve the question of responsibility. It won't fix any technical issues that might arise.
 

controlled

Senior Member
Thanks for all the info guys.

The machine in question is a used box die-cutter made by Bobst. The local Bobst office has confirmed that the machine will run fine using 460V 60hz.

My quote will obviously indicate what the supply voltage/frequency will be.
 
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