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

Thread Starter


Joined Jul 2, 2015
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.


Joined Jan 8, 2017
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 ?



Joined Jul 18, 2013
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?