Motor Name Plate Decoding

[celichi]

Hello All,

I hope we are all doing great and have a healthy and happy 2023!!

I was wondering if anyone could help me decode this Motor Name Plate.

I am trying to setup the 753 Parameters as part of the Quick Start / Static Tune.

The NP has 3 rows, and I am not sure which values to use.

Why are there 3 rows, and how do I know which one is correct...?

Kind regards - Paul

 

[Robb B]

There's multiple lines because they give you different voltage/frequency parameters. You need to know what voltage and frequency you are using (480v @ 60hz is the norm, but with a VFD you can specify whatever you want for output). The important part would be getting the FLA correct in the drive to match whichever parameters you use since the drive provides the overload protection directly. I am not sure how they have two values for 480v @ 60hz and two different speeds. I'd default to assuming the 3rd row is appropriate, but maybe there's more information in a manual or something.

 

[mobil1syn]

googling says the IE ratings is IEC and the MG rating is NEMA for efficiency

 

[Bit_Bucket_07]

In Canada, it's been my experience that a 600 VAC 3 phase service is more common than is 460 VAC. You should make sure that the drive is setup for 460 VAC maximum voltage output for this motor.

 

[Robb B]

In Canada, it's been my experience that a 600 VAC 3 phase service is more common than is 460 VAC. You should make sure that the drive is setup for 460 VAC maximum voltage output for this motor.

Typically industrial plants will operate at 480v, as more variety of motors and such are available. Places that have a lot of pumps will more likely have 600v in my experience. I believe US standards are 400 and 575V. Just as a note, 600V devices will have an amp rating equal to the horsepower. For example: 50HP motor at 600V has an FLA of 50A. This makes math a lot easier at 480V it's 1.25x the HP rating, slightly harder math.

 

[celichi]

Thank you everyone for the replies and information.

Feed to the Panel is 480 VAC 60hz, this installation is in USA.

I noticed that just above the 3 rows of data...

"60hz: sf 1.15 CONT NEMA MG1"

So maybe, this motor is Nema MG1 rated for efficiency, and thus I should be using row 3.

I will report back to the thread the reply I receive from Siemens Support.

Thank you again!

 

[Robb B]

Thank you everyone for the replies and information.

Feed to the Panel is 480 VAC 60hz, this installation is in USA.

I noticed that just above the 3 rows of data...

"60hz: sf 1.15 CONT NEMA MG1"

So maybe, this motor is Nema MG1 rated for efficiency, and thus I should be using row 3.

I will report back to the thread the reply I receive from Siemens Support.

Thank you again!

The motor is both IEC and NEMA rated. You use the frequency that is applicable in your area, 60hz. I'm not sure what sort of wizardry produces two different power ratings for the same applied voltage and frequency.

 

[mylespetro]

Typically industrial plants will operate at 480v, as more variety of motors and such are available. Places that have a lot of pumps will more likely have 600v in my experience. I believe US standards are 400 and 575V. Just as a note, 600V devices will have an amp rating equal to the horsepower. For example: 50HP motor at 600V has an FLA of 50A. This makes math a lot easier at 480V it's 1.25x the HP rating, slightly harder math.

Opposite coast here, but I almost always run into 600V (575V) in industrial settings. A small smattering of 480V here and there, but 600V seems to be the most common anecdotally in my experience.

 

[plvlce]

I'm not sure what sort of wizardry produces two different power ratings for the same applied voltage and frequency.

+1

Seeing separate lines for 50 vs 60 Hz or for different voltages is common, but lines 2 and 3 being present simultaneously is bizarre and I'm curious to hear an explanation.

 

[kamenges]

As already stated, the IE ratings are IEC ratings and the MG rating is a NEMA rating. Looks to me like the concept of service factor doesn't translate quite directly into the IEC ratings. Basically the MG1 rating times the service factors gets you very close to the IE3 rating of the motor. So the IE3 rating pushes the motor to it's design capacity while the MG1 rating derates the published capacity by the service factor.

In effect this is probably a moot discussion. The motor will deliver what the load will take. The difference in speed in the two 60Hz ratings is associated with the difference in slip needed to get the extra torque to get the IE3 rating. I would tend to use the MG1 numbers just because they are a bit more conservative but in the end I don't think it matters as long as you don't mix rows.

Keith

 

[Puddle]

According to this datasheet, there's a hidden fourth option for 690v operation.

https://mall.industry.siemens.com/m...jYWxlMT1lbiZkb2N1Lmxhbmd1YWdlLmxvY2FsZTI9ZW4=

Source page if that link isn't global: https://mall.industry.siemens.com/mall/en/uk/Catalog/Product/1MB15332DA034AA4

I think the difference between the two 460v options is just the efficiency rating, it's the only reason I can see why there would be a difference in speed, torque and power output from the same voltage and frequency specification. It's not clear on the nameplate as there's different standards, but on the datasheet it shows IE2 at 84kW and IE3 at 75kW.

 

[JesperMP]

I'm not sure what sort of wizardry produces two different power ratings for the same applied voltage and frequency.

It is for 2 different operating points. One is 3575 rpm and the other is 3578 rpm. This is probably because of differences how IEC and NEMA defines efficiency classes.

 

[Robb B]

Can anyone explain how there's two different speeds for the same frequency?

At 60 Hz, a motor with two poles operates at 3,600 RPM with no load and about 3,450 RPM with a load:

(Hz x 60 x 2) / number of poles = no-load RPM
(60 x 60 x 2) / 4
7,200 / 2 = 3,600 RPM

Unless this is a particular kind of synchronous motor designed to run at exactly it's given rpm, and not a standard squirrel-cage induction motor.

 

[JesperMP]

Can anyone explain how there's two different speeds for the same frequency?

The name plate values are for operating at the 'nominal load'.
The question is then what is the 'nominal load' definition. I guess this definition is different for IEC and for NEMA.

edit: The difference could be what cooling can be assumed and/or what ageing of the insulation in the windings can be tolerated in the motors lifetime.

 

[kamenges]

I agree with JesperMP. The NEMA rating assumes a 1.15 service factor, which provides margin between the rated power and the power that reaches the design thermal limit of the motor. The IEC rating simply works off the design thermal limit of the motor. It is why the IEC rating is at a lower speed and a higher power. The IEC rating is at a higher load, resulting in more slip.

Keith