help plz 3 phase converter

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The inverter gives 230V (with respect to neutral) on each phase, but the voltage from one phase to another is 400V.  That will cook your control circuit very quickly.

@Onoff suggestion would work.  With a bit of unpicking and rewiring you could feed the control transformer from the single phase L and N that is feeding into the 3 phase converter and it would be happy.  so take that blue and black wire out of the contactor bottom left, and feed those from the L an N going IN to the 3 phase converter.


Wouldn't that mean the control transformer having no isolation other than the mains plug on the converter?

Yep, jump the neutral straight to one of the transformer primary wires.

I wonder if any of the converter lines feeding R,S or T are "true" lines or capacitor derived. If true line then feed the other side of the trannie primary from that. 

Had to find & steal some felt pens...

20190428_112858.jpg

 
Lol im not joining wires im just pointing out on diagram 380v and 220v N ,W join the same line and goto 24v. its just a part of the drawing i dont understsn lol.

I think it ref to it can run on either 380 or 220.? Not sure.

The inverter gives 230V (with respect to neutral) on each phase, but the voltage from one phase to another is 400V.  That will cook your control circuit very quickly.

@Onoff suggestion would work.  With a bit of unpicking and rewiring you could feed the control transformer from the single phase L and N that is feeding into the 3 phase converter and it would be happy.  so take that blue and black wire out of the contactor bottom left, and feed those from the L an N going IN to the 3 phase converter.
Could I i take black and blue from coil top left and cover them and feed blue brown from vdf blue to blue and brown to black. Just a thought 

Thanks for all your help

 
Lol im not joining wires im just pointing out on diagram 380v and 220v N ,W join the same line and goto 24v. its just a part of the drawing i dont understsn lol.

I think it ref to it can run on either 380 or 220.? Not sure.

Could I i take black and blue from coil top left and cover them and feed blue brown from vdf blue to blue and brown to black. Just a thought 

Thanks for all your help


The transformer has a 220V primary.

If the supply is 220V 3 phase without a neutral then the drawing shows the transformer connected across R&T.

Or

If the supply is 380V 3 phase + neutral, then the transformer is connected across R&N.

Your motor rating plate will likely show 380V star / 220V delta? (Or similar).

I assume your ramp is continental one like the one here is (Grazia make)? 220V 3 phase was quite common in parts.

See the plate on the original motor plate I have here and the delta symbol above the 254V and the star symbol above the 440V.

20190428_153411.jpg

I worry if, via the converter, you've slapped "380V" across that transformer primary you might have cooked it. Can you test the primary for continuity?

 
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I suspect the transformer is still working if the "up" function works as the transformer will be energising the contactor to run the motor for up.

The fact it won't go down may suggest it has already cooked the "down" solenoid?

Until a solution is found I recommend the OP does not keep on trying to use it.

@Onoff  The "simple" solution is connect the feed to the control transformer to the real mains input to the 3 phase converter.  Assuming that is fed from an isolating switch, the transformer will only be energised when that isolator is on.

 
Hi I've checked all outputs from converter and control box and none are above 220 it spikes on my meter to 250s.

It's a very small converter and can't produce that amount.

Gone back to N AND W together set the converter to 220v so coil gets constant 220v when buttons is pressed contactor makes a clonk when up is pressed and again when it hits limit. It's running on 24v I've checked down button on 2 and 5 and reads 0v press it and it reads 24 but no sound from contactor when button is pressed ? but power is there. I think the contactor could be shot. Is there a way to test it. I've check all othere wirering.  and what primary do you want me to check I'll slap my meter on it ive checked all WVU outputs as I turn up the speed on vdf volts go up on all 3 equal set it 2 220v or there abouts and it works like a dream rises fast for the size and weight of ramp I can slow it down with rpm or just reduce the juice I'm not sure how it does it via hz or volts bit it work for me. as I change the speed the coil sound changes must be hz and 50hz is quite but trips the vdf to much power so it's around 36 now not sure how or why but it works. It's just the down button that s giving me jib. May have to get an expert in   😭 had the motor going backwards a few times I just reversed  it on vdf .

Also grey wire and blue have 220v or there abouts  and goto coils blue and black 220v side. And it works.. single phase don't work and coil just rattles all.over the shop.works much better if I can control the lower to coil but thus freaking down button has got me why me😂 my motor plate pic.

20190416_131715.jpg

 
Solenoid  is fine I can lower the ramp with my 12 volt battery charger by touching the clips onto solenoid spade ends. It works fine.  I think it could be contactor and op is not using it to put any cars on it has to be sunk into garage floor and  fixed down and wired correctley . It is being tested under it's own weight with me clear . Safety first lads done enough site inductions in my time. But hey thanks for looking out for me 👍

 
If I am reading the circuit right, the contactor is only used to turn the motor on for UP.  The down solenoid is powered from the 24V transformer via the pushbuttons.  If the buttons don't energise it there is a fault with the wiring or one of the buttons.

 
That makes sence . But the down button must work as I put a test on 2 and 5 from solenoid and it comes from 0v to 24v when button is pressed.  I'm at a complete loss lol time to call in an expert I think

 
Verify continuity from the transformer to one side of the solenoid - the line with no limit switches in.

Verify you have 24vdc coming off of the bridge rectifier.

Set your meter to DC. Attach one probe to the - (negative) on the bridge rectifier. 

Stick the other probe on the down button. Press the button. If 24V is getting to there move on to the terminal block. See to what limit it goes and whether it's coming back.

 
Hi Just a thought could I use a jumper on the 24v block white one to by pass buttons/ limits. To test. Would I do the same to the lower limit switch it could be stuck on thinking it is all the way down.  I can't read the drawing to well do you know how I could by pass the lower limit switch and what numbers I would jump to bypass should go down lol . The way i see jt on diagram,

Jump 6 and 1 .    1 being solenoid and 6 lower limit. would I damage anything . or is it 2 and 1 . think I understand diagram a little more now .  2 limit switch are open and 2 closed 1 closed and 1 open are connected pair on drawing but 1 switch .  2 with up and motor  and other 2 with down , solenoid and magnetic valve. Is it advisable to jump the numbers 

Thanks for your help  

I've already tested 24 volt rectifier from transformer  its not stable its up and down i got it sa close to 24v with vdf its from 12 to 35 havnt tried continuity from solenoid to trans 

Tested  block 2 and 5 with button pressed i get 24v release button 0v. And it's a stable 24v. Earth to 2 or 5 same results stable 0v or 24v I have to try this lower limit can I jump it or do I have to take it apart.  It's right under the sissor bit little silly thing and it looks like it could chop me in half not liking the idea of going in there with some sort of supports.

I'll have a look tomoz .

 
Power:1.5KW
Rated Current:8A
Voltage:AC 220V 50HZ/60HZ
Capacity:4.0KVA(1.5KW/2HP)
Output Voltage Regulation Mode:pWM control

Screenshot_20190429-125334_eBay.jpg

 
You are heading for expensive problems, inverters don’t like the output being switched by a contactor. The inverter is your drive control with start/stop functions built in.

I asked for the make and model, would you post them so I can find the manual.

This isn’t an easy job for a DIYer to take on due to the dangers involved and I’m not overly keen on getting involved.

 
I posted motor plate see above. I'll post copy of manual later after graft.

All I can tell you is I don't use the vdf to control the speed I set the speed then use the up button to switch motor on I only used the speed controller with up button pressed to find the right volts for motor to kick in once set I use up button on ramp not speed controller I know vdf unit is for speeds and feeds on a cnc machine. I'm just using it for wvu supply  if any of that makes sence it was the cheaper option. . I here you when you say vdf don't like contactor . But it has under volts and over volts cut outs on vdf. Maybe it will give up the ghost who knows.

 
Alright calm down tony it's Monday .  I'm not a complete fool what's the point of coming to a forum for help as a diy er if only to be told go away get a sparky. I can take nonfor an answer no problem. Your going to help me or not alot of it I don't understand but tbf mate I'm having a go and if your worth your wait in salt you would tell me how to be safe when doing what I'm doing never mind giving me any sound advice what so ever. Apart from have you got a manual.  woof . Lol you barking . It ent gone woof yet your the only one woofing . Is this how you treat apprentices or any one trying to learn .ffs lads and woofers. Trying to send the manual.

I've tested all buttons and limits with power OFF!!!!!! just to be safe.numb nutts. with ohms ..down button. is 8 and 2 beep when pressed no beep when not pressed and you lot had a drawing you understand and I don't  lol all limits and buttons work even the aux one on control box beep beep. So it seems it's the vdf cheap nasty China import it's a complete 're wire to 240 and change motor. As the N on diagram is key .I've tried 240v to coil in control box blue to blue brown to black From vdf input from house mains on a 13 amp plug  and coil in control box rumbles like crazy. I've tested the house input to vdf and it's 249v. Don't ask me why. im trying to right a reply and you keep butting in . now I'm getting slagged as a useless f diyer come on😭 omg your going in.my wallet plz mate . I tell my 17 year old son education is key son it only takes a fool to tell you how to do it common sence son. I said to him hey son get the chance to got uni and they teach you how to be objective that's how all fields of engineering move forward cuz young kids try new things. Instead of giving somthing meaning full you want to belittle and shame ppl and make fun I'm lucky I'm older and can rip you a new one with almost 500 posts you should be ashamed mate. I'm joe public wanting to learn and you have added nothing don't matter how simple the questions I'm asking and you may get frustrated by it .I'm multi skilled in a lot of fields and tbh I've got money lots of it I've got 5 houses between me and my wife and still I try to learn I worked on sites all my life not in electrics but hey who cares do you care enough to give me some real sound advice .  I'm smelling a Narcasist. never mind burning wires lol🤣🤣🤣

 
Then Tony should help you to learn more about motors. But he can't tell me hmmmmmmmmm. Why. I'm a diy  er and it must be my wallet. Well if Tony has got knowledge share it. 😊

 
Well what a shame this thread has deteriorated into such a do about nothing. Perhaps many had the opportunity to learn  ?

Attitude used to be in old English ‘ A-***-dude until PC changed it. Perhaps **** should be put away and calm and peace restored then maybe we might just see progress - jeez I’m sounding all theological!! 

 
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