Motor not properly grounded? (2/3 fuses are blowing)

Thread Starter

trherzfeld

Joined Jul 2, 2015
9
Hey there,

I have a very small motor that can be wired for 3 phase high voltage (460) or a lower voltage at 230/208. I have a 208V 3 phase wye system and every time I try to connect the motor to it blows fuses on two out of the 3 legs. Now, just for experimentation, I ended up connecting the motor for a high voltage setting and it did NOT blow fuses, but obviously it ran at too high of amps, so I need to figure out why it keeps blowing fuses at my low voltage wiring. If I remember correctly, since it's only blowing 2/3 fuses, that should mean that the unit is not grounded properly. Is this correct or can anyone go into more detail for me? Thank you so much.
 

LesJones

Joined Jan 8, 2017
4,190
I don't think it anything to do with grounding. When you say that you have "a 208V 3 phase wye system" do you mean that the 208 volts is between neutral (Star point.) and each pase or do you mean that there is 208 volts between phases ?

Les.
 

MaxHeadRoom

Joined Jul 18, 2013
28,686
It should be grounded, if not already.
But it should still work OK with no ground conductor.
The terminal taps for Star-Delta are usually very easy to change, do you have a Pic of the terminal box?
Max.
 
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