480VAC to neutral (277V) wiring

[Rson]

It seems to be a Grundfos ML71BB motor.
According to the manufacturer, it is to be connected in delta for 440-480V.
edit: Actually it is not delta. See the "wiring diagram" by the link above on how to connect it.
https://product-selection.grundfos.com/product-detail.product-detail.html?custid=GMA&productnumber=85900703
I think that the name plate is possibly labelled wrongly !!
On the website, the motor is rated at 0.75 kW, on the photo the label says 0.75 hp.
Whatever you do, the motor is rated at 2.1A (*) when connected as desribed, so you must protect it for 2.1A, definitely not 4.5A.

*: On the website, it says cryptically
"Rated current: 1.9 A
Maximum current consumption: 2.1 A"
So what is it, 1.9A or 2.1A ?
Anyway, it is defiitely not 4.5A

There is a motor protective manual starter to protect via FLA. The fuses only protect the wiring, and per NEC table 430.250, a 1HP motor is listed as 2.1A FLA, and allows max fusing of 6A, optimum fusing at LPJ-SP is 3-2/10.

 

[kolyur]

I take it you are using a non-time delay fuse, in which case Table 430.52 allows 300% of FLA. We normally use time delay and size at 175% of FLA.

 

[Rson]

I take it you are using a non-time delay fuse, in which case Table 430.52 allows 300% of FLA. We normally use time delay and size at 175% of FLA.

I'm actually following Bussman's fuse recommendations from the SPD 2017 for LPJ-SP