Connecting 2.2kw vfd to Mains supply

[the great waldo]

Hi
Me again, I hope this isn't a stupid question. Is it necessary to have the input phase correct on the ac mains side of a vfd. The reason I asked is the mains plugs over here in Austria are not orientated, unlike the British mains plugs. Using the European plug if correct orientation is required i'm going to have to use some kind of marking. I don't want to blow up the hitachi vfd as it wasn't cheap.

Cheers

Andrew

[Doddy]

My view, and nothing that I've seen in the Hitachi manual tells me otherwise, is that the VFD would work with the phases reversed.

Clearly, the recommendation must be to wire the phases correctly to avoid confusion and hazards later on. But, it'd work regardless.

[Clive S]

Hi
Me again, I hope this isn't a stupid question. Is it necessary to have the input phase correct on the ac mains side of a vfd. The reason I asked is the mains plugs over here in Austria are not orientated, unlike the British mains plugs. Using the European plug if correct orientation is required i'm going to have to use some kind of marking. I don't want to blow up the hitachi vfd as it wasn't cheap.

Cheers

Andrew

In the UK the neutral is bonding to the Earth at the consumer unit generally with the phase being fused.

But in some countries the mains is supplied by a split system ie 220V would be 110 - 0 - 110 with the earth being the 0 that is why the plugs are not polarised they also use two pole mcb's one in each leg.

I think you will be fine which ever way round you connect it. Do you know what system you have re earthing and breakers ie two pole or singe?

[the great waldo]

Hi Clive

The breakers are 2 pole according to the switch diagram on the breakers. I don't think the mains here is a split system. 3phase here is at 380v: all my larger tools that I dragged over from England years ago work fine here. From what i've seen on the internet vfd's have basic rectification at the front end so i'd imagine it should work ok. I just wasn't sure if hitachi put some kind of fancy electronics in the vfd that is polarity sensitive. I just had a look in the distribution box without the cover and the breakers are double pole but phase and neutral each use one side of the breaker.

Cheers

Andrew

In the UK the neutral is bonding to the Earth at the consumer unit generally with the phase being fused.

But in some countries the mains is supplied by a split system ie 220V would be 110 - 0 - 110 with the earth being the 0 that is why the plugs are not polarised they also use two pole mcb's one in each leg.

I think you will be fine which ever way round you connect it. Do you know what system you have re earthing and breakers ie two pole or singe?

[A_Camera]

Hi
Me again, I hope this isn't a stupid question. Is it necessary to have the input phase correct on the ac mains side of a vfd. The reason I asked is the mains plugs over here in Austria are not orientated, unlike the British mains plugs. Using the European plug if correct orientation is required i'm going to have to use some kind of marking. I don't want to blow up the hitachi vfd as it wasn't cheap.

Cheers

Andrew

I guess you have already connected the VFD and found out that it does not matter which way you plug it in, but just to make it clear for everyone else as well...

If you use a one phase VFD it does not matter which way you connect it, as long as you connect one wire to phase and the other to neutral and the third (yellow/green) to PE (protective earth). The main thing is not to confuse earth and neutral, those two are TOTALLY different in the European net. Inside the VFD it makes no difference if neutral and phase connections are switched, so you can safely plug in the VFD in any plug orientation, it really doesn't matter, just like the vacuum cleaner you use, you never know which is phase and which is neutral, it still spins the same way and works just as well.

[the great waldo]

Hi A_Camera

I wired the motor up and as usual nothing worked, but after adjusting some settings on the vfd I got it to rotate the motor. Now the fun starts with getting the speed settings and all the other settings adjusted to get the motor running properly. Luckily no sparks or smoke so far, just not much time at the moment to do the adjustments and mount the 80mm motor bracket instead of the 43 mm one. I would like to thank everyone here for their input and help. I must say that the Hitachi manual is not very inspiring for a beginner like me.

Cheers

Andrew

[A_Camera]

Hi A_Camera

I wired the motor up and as usual nothing worked, but after adjusting some settings on the vfd I got it to rotate the motor. Now the fun starts with getting the speed settings and all the other settings adjusted to get the motor running properly. Luckily no sparks or smoke so far, just not much time at the moment to do the adjustments and mount the 80mm motor bracket instead of the 43 mm one. I would like to thank everyone here for their input and help. I must say that the Hitachi manual is not very inspiring for a beginner like me.

Cheers

Andrew

Hi,

That's one reason why I chose the Bosch Rexroth EFC 5610... excellent documentation, easy to start up just by changing a few parameters. So far, of all the over 400 pages I found only one error in it, which isn't exactly an error in the documentation, more like they forgot to describe a function which they make reference to. Anyway, I am very happy with it. OK, "inspiring" is the wrong word, but I am very much used to reading manuals, so I am happier with 500 readable pages than 16 difficult to understand ones. Being an engineer with 40 years of experience helps of course...