Motor Nameplate Question

[joec]

Can someone please tell me the difference between to two 460 Y configurations listed on this nameplate? The motor is connected 460 Y drawing 7.5A. I would just like to understand the difference between the two ways of terminating this motor. Misprint on nameplate?

 

[templdl]

Can someone please tell me the difference between to two 460 Y configurations listed on this nameplate? The motor is connected 460 Y drawing 7.5A. I would just like to understand the difference between the two ways of terminating this motor. Misprint on nameplate?

It almost appears as if the last 460v is a misprint and should be 480v.

 

[mike_kilroy]

It almost appears as if the last 460v is a misprint and should be 480v.

ya but.... then the two amps & kw's are then backwards.....

 

[rbalex]

It is the difference between full and 80% loading at 460V. The motor is IEC not NEMA rated. The numbers are correct just Siemens EU's interpretation of NEMA/ANSI requirements. ("cos" is the powerfactor")

 

[topgone]

Can someone please tell me the difference between to two 460 Y configurations listed on this nameplate? The motor is connected 460 Y drawing 7.5A. I would just like to understand the difference between the two ways of terminating this motor. Misprint on nameplate?

I did some quick calcs and the numbers are correct, no errors whatsoever!
Check using: Motor amps = P/[sqrt(3) x voltage x PF (or cos) x NOM. EFF.]

V	Hz	A	kW	cos	NOM> EFF.	CHECK AMPS
230	50	13.6	4.00	0.86	85.8	13.61
400	50	7.8	4.00	0.86	85.6	7.84
460	60	7.5	4.55	0.87	87.5	7.5
460	60	6.3	3.70	0.84	87.5	6.32

 

[GoldDigger]

It is the difference between full and 80% loading at 460V. The motor is IEC not NEMA rated. The numbers are correct just Siemens EU's interpretation of NEMA/ANSI requirements. ("cos" is the powerfactor")

That is also consistent with the very slightly higher RPM (1/min) values for the two lines. Lower slip.
Any idea why both the 100% and 80% figures are shown only for the 460 delta case? Is that the NEMA/ANSI requirement interpretation you are referring to, since 460 would be a "US" voltage? I would feel a lot better if that were made explicit in the labeling somehow.

 

[rbalex]

That is also consistent with the very slightly higher RPM (1/min) values for the two lines. Lower slip.
Any idea why both the 100% and 80% figures are shown only for the 460 delta case? Is that the NEMA/ANSI requirement interpretation you are referring to, since 460 would be a "US" voltage? I would feel a lot better if that were made explicit in the labeling somehow.

I confess I don't remember, especially since it was never a NEMA/ANSI requirement. It's been since 1998 that I worked an IEC project. As I recall, the vendor told me they wanted to emphasize their product had a uniform efficiency across a general operating range typical of many US domestic refineries. Many NEMA manufacturers were creating similar tables although not necessarily on the nameplate. If folks do something long enough, they believe it's a requirement.

It doesn't affect the data on the nameplate though.

 

[rbalex]

This Siemens document may give a bit more background.

 

[joec]

Thank You

Thank You

Thank you for all your replies. Very much appreciated!