Thread: VFD outputs

Originally Posted by nigelpearson

I think that is safe, as long as you never switch it over when the VFD is powered up!

It totally safe to switch even with the VFD powered up as long as the VFD is not under load (ie driving a motor - I switch one in my shed multipole times a day.
this is the VFD that drives either of two identical grinders. When I open the box the encloses the cross over switch, this opens a microswitch which which turns off the motor (VFD stays on) then I hit a reset switch and start the second grader.

The reason the OPs delta to start switch works is that the moto RPMs will not change much during the switching. However, I still don't see the need to go from operating a motor at full power rating to half power rating.

Originally Posted by jcatcmc

Hi, Thanks for the replys so far, just got back to this project 1.0 KW motor nameplate tells me 415 v. star connected, 220 v delta connected. Trouble is connecting VFD 220 v output to star the motor lacks torque to do the job, connecting VFD to delta configuration it can't handle the starting current. I tried a 2.5 KW VFD still locks out on over current . The motor is a rapid traverse drive on a mill the only time it dies is when lifting the knee, all other drives ok. Something I can live with.

regards to all

So when the motor is delta connected you get an over-current error from the VFD? What rated current are you entering into the VFD, the value stated on the motor?

Regarding this subject it was suggested I try reading a PDF document `VFD`s for newbies`unfortunately not available to me when logged in to the WW forum . Anyway it looks like we are starting to lose track of the original problem as described in post # 6 as this goes along.

I would like to add a comment about the mentioned Delta/ Star (starter ?) It would certainly work as described but it is still banging it on DOL with the starting current up to 6 times FLC on start up then switching to star, the only advantage I could see is to save on running costs. The terms double power and normal power i`m not clear on. Torque is not going to be any thing to write home about . Its easy enough to do but in 50 years of contracting I've not seen it done.

Regards the question what current value I am entering into the VFD I must of cheapskated as that input is not available . An earlier suggestion was to increase ramp up time, didn`t help, even over smoko.

Hi Jcatcmc,

There will be a way of entering or allowing the VFD to supply the motor start current !

The ramp up time is there to allow the motor to have a controlled start up. Shortening the start up time, will not allow more current to the motor than that value you have either programmed in, or allowed the VFD to determine for itself.

Originally Posted by jcatcmc

Regarding this subject it was suggested I try reading a PDF document `VFD`s for newbies`unfortunately not available to me when logged in to the WW forum . Anyway it looks like we are starting to lose track of the original problem as described in post # 6 as this goes along..

You have to register to get access to pics and docs.

Meanwhile I attach a copy here.
VFDs4Newbies.pdf

Originally Posted by jcatcmc

Regarding this subject it was suggested I try reading a PDF document `VFD`s for newbies`unfortunately not available to me when logged in to the WW forum . Anyway it looks like we are starting to lose track of the original problem as described in post # 6 as this goes along.

I would like to add a comment about the mentioned Delta/ Star (starter ?) It would certainly work as described but it is still banging it on DOL with the starting current up to 6 times FLC on start up then switching to star, the only advantage I could see is to save on running costs. The terms double power and normal power i`m not clear on. Torque is not going to be any thing to write home about . Its easy enough to do but in 50 years of contracting I've not seen it done.

Regards the question what current value I am entering into the VFD I must of cheapskated as that input is not available . An earlier suggestion was to increase ramp up time, didn`t help, even over smoko.

The reason I asked about current is, I was told by a support technician at SEW Eurodrive that when you change a motor from Star to Delta connect, to use with 240V VFD, the current parameter of the VFD can be set to Square root(2) time the current rating on the motor. So that's approximately 1.41*current rating. This gives a higher limit and reduces the chances of over current triggering. It helped a lot in my application.

Can you provide a manual for the VFD you have or product link. I'd like to see the available user parameters.

Here you go monchochos, photos are the highest my skill set will go. If you find an input I hope its not too obvious.


IMG_20200825_204218651_HDR.jpgIMG_20200825_204208329_HDR.jpg

I don't see the "rated current" parameter either. I wonder what current limit value it uses. Parameters 13, 15 & 16 are a bit interesting, anymore info about them? Is the manual available online?

目 录www.et.byu.edu › ~sorensen › A2 VFD Manual. How about that , I scare myself at times

Several budget end VFDs I have encountered in the last few months do not allow for maximum current maxima to be set.

Several budget end VFDs I have encountered in the last few months do not allow for maximum current maxima to be set.

I assume you are getting the OC-u error ( Acceleration overcurrent)? Like others have mentioned, looks like the only option is to increase acceleration time for this fault.

Thanks for all the help along the way I feel I am a bit more enlightened, just confirms you only get what you pay for and obviously I didn`t pay enough. With that said I doubled my budget and fired off a request for info from a `professional business with many years of experience ` judging by the reply just another guy selling from his mum,s garage.

At this point I will ask if anyone has any recommendations ( VFD for Starting a 1.0 KW motor , unloaded 220 volt Delta connected FLC 5.0 A 230 Volt input ). Rest easy as this is getting close to my swan song on this subject.

Regards to all

Originally Posted by jcatcmc

At this point I will ask if anyone has any recommendations ( VFD for Starting a 1.0 KW motor , unloaded 220 volt Delta connected FLC 5.0 A 230 Volt input ). Rest easy as this is getting close to my swan song on this subject.

Whatever you buy make sure you can get hold of and read the manual before you buy to make sure it has max current setting capability.

Huanyang VFDs were one of the first generic brands adopted by members about 10 years ago and are still around but now cost a bit more, Lots of members have these and we know where the errors are in the manual. I've had 10 of these VFDs in my shed doing various things - still have 3 left - no failures. I've replaced 5 of them with Vector drive Powtrans. The Powtrans boot fast and are rugged and fully featured. I've been recommending these to mens sheds for their dust extractors - zero problems. I get them direct from the factory in China - no web ordering - its done by email - Shipping is $$$$ but the units themselves are relatively cheap so it sort of cancels itself out a bit. Do a search for Powtran and this will turn up how to do it.

Have dabbled with with Telemechaniques, Delta, Honeywells - all really good VFDs.

I have never installed one but have seen the manual for the Folinn VFDs sold by Conon motors and its a fully featured VFD.
https://cononmotor.com.au/product/1-...erter-vsd-vfd/
They cost a bit more than the Huanyangs but they're in Melbourne so you get support and also I believe its a 2 year warranty.
I recommend these for people who are worried about ordering/buying stuff from china.

I see Bob recommended Conon motors. I would like to second this recommendation. I am happy with the one I purchased and it does everything I want it to and more. I have not had much experience with these to say if there is a better one on the market. My main reason for my recommendation is the pre and after sales service. I rang before buying and was happy with the quality and quantity of advice. When I went to install it I was a bit unsure about a few things. It was a Saturday afternoon but I thought I would try the number. The person on the other end could not have been any more helpful. If I were to buy a second one they would be my first port of call.

Steve