vfd Hitachi elb and magnetic connector ?

[medic0079]

So I settled on A VFD (Hitachi) and now I have some questions. I am going from 220 single phase to 220 3 phase. My plan was to go from 30A circuit breaker through 10G wire to 20A fuses (sized per the manual) to the VFD to the motor. The manual says that I should install a ELB, and a magnetic connector. Between the power source and the input. What is the purpose of these and are the necessary. Also my understanding is that the power goes to L1 & L3 (why is this labeled N in the manual) there is no neutral, and the VFD is grounded is this correct? is it ok to use the neutral wire as a separate ground between VFD, motor, and Panel ground? Finally there are two auxiliary cooling fans on my mill blowing at the head is there a way to run these through the VFD also (I assume they are 3 phase as they are wired in to the motor) or should I just buy some replacement 120V fans and run them on a separate circuit? They are small square muffin style fans.
Thanks for the advice.

 

[JimDawson]

So I settled on A VFD (Hitachi) and now I have some questions. I am going from 220 single phase to 220 3 phase. My plan was to go from 30A circuit breaker through 10G wire to 20A fuses (sized per the manual) to the VFD to the motor. The manual says that I should install a ELB, and a magnetic connector. Between the power source and the input. What is the purpose of these and are the necessary. Also my understanding is that the power goes to L1 & L3 (why is this labeled N in the manual) there is no neutral, and the VFD is grounded is this correct? is it ok to use the neutral wire as a separate ground between VFD, motor, and Panel ground? Finally there are two auxiliary cooling fans on my mill blowing at the head is there a way to run these through the VFD also (I assume they are 3 phase as they are wired in to the motor) or should I just buy some replacement 120V fans and run them on a separate circuit? They are small square muffin style fans.
Thanks for the advice.

Just to clarify a bit, the device they are referring to is a magnetic contactor (motor relay). Not sure what they mean by an ELB, could be a line filter. Sometime helpful if you experience electrical noise on control wiring, electrical noise can fowl things up a bit in sensitive control circuits. Not likely in this case. The contactor provides a remotely controllable disconnect for the VFD, not required in this case.

I have my VFD's properly fused, but wired directly to the breaker, eg Breaker >>> Fuse >>> VFD. I leave them on all the time.

Just a side note, never put a disconnect between the VFD and the motor (unless absolutely required by code as a local service disconnect)

It could be that L1 - L3/Neutral, is for marked for European wiring where 220 V has a neutral.

Ground the VFD, the panel GND, and the motor ground to the ground lug on the VFD.

Do not use your neutral as a ground. Pull in a dedicated ground wire. If you are using the neutral in your panel for control wiring, you will need to bring in 4 wires. Normal residential wire colors would be Black, Red for the hot wires, White for the neutral, and Green for the ground.

Check the voltage on the muffin fans, they could be 240V, I have never seen a 3 phase muffin fan. My guess they have separate wiring to them.

Hope this helps.

 

[rdhem2]

Mr. Dawson pretty much nailed it.

About the only thing I can add is the ELB is a filter on the line side to help suppress nasty harmonics and such from going up line to other devices in your system.

You are going to like the Hitachi drive.

 

[medic0079]

So I will be ok if I connect from breaker to fuse to vfd then. I have some (red, black, bare green and white) 10 gauge wire that I can use. should I install two grounds? one on the bare wire that is usually ground and one seperate I.E. green wire? I dont need both do I? Sorry for the dumb questions. Here are some pics of the muffin fans. I dont know if they even still work. I will be cleaning the top up before starting the mill.

 

[JimDawson]

So I will be ok if I connect from breaker to fuse to vfd then. I have some (red, black, bare green and white) 10 gauge wire that I can use. should I install two grounds? one on the bare wire that is usually ground and one seperate I.E. green wire? I dont need both do I? Sorry for the dumb questions. Here are some pics of the muffin fans. I dont know if they even still work. I will be cleaning the top up before starting the mill.

Yes, Breaker>> Fuse>> VFD

No, you don't need both grounds. Just make sure to connect all of the grounds to a single point, and not in a loop.

On those fans, there should be a data tag somewhere, normally right on the motor. If you can find the voltage on them, I or someone else will be able to help you out. Connecting them to the VFD is not a good idea, and may not be even possible due to voltage differences. It looks like those fans actually blow into the drive system, I have never seen that before.

The only dumb question is the one not asked. This forum is all about passing on knowledge.


EDIT: I am guessing that the two gray wires in the motor box power up the fans, thus they are probably 240V, single phase. You will have to power them up off of a relay or a supply prior to the VFD. There should be an isolated relay in the VFD that can be programmed to close on motor run.

 

[medic0079]

Cool thanks for the help. I planned on climbing up to the top of the mill and cleaning it all off tomorrow. I just havent had a chance since I got it I've been removing surface rust, cleaning and getting it moved into position in my shop. I guess its time to break out the ladder and address the top of the mill. Thanks again for the help.
Noah

 

[medic0079]

One last question does it matter if I wire my motor star or delta? Hitachi manual says u/t1 v/t2 w/t3 I assume this is delta but my motor is labeled uvw on one side and xyz on the other I think it's in delta with xyz all linked together should I change this to ux vy wz? Does it even matter?

 

[JimDawson]

One last question does it matter if I wire my motor star or delta? Hitachi manual says u/t1 v/t2 w/t3 I assume this is delta but my motor is labeled uvw on one side and xyz on the other I think it's in delta with xyz all linked together should I change this to ux vy wz? Does it even matter?

It looks like your motor is wired for high voltage, probably 460V. So yes you need to reconnect it for 240V

This is the best picture I could find, see if this matches the diagram on your motor.



If you can post a picture of the motor data plate and the wiring diagram it would be helpful

 

[medic0079]

this is about the best I can do of the 220 side it is well worn and barely readable. the wires appear to be uvw on the left but it is hard to tell the middle and bottom right side is xyz and are linked together. best I can read this looks to be correct with x1 y1 and z1 linked u's v's and w's linked

 

[JimDawson]

The data tag was very helpful even though the diagram was worn. It allowed me to find a similar motor.


Ignore my post above, Here is the correct diagram. You are wired for 230 V. All you have to do is connect the power wires like they were.