No Volt Release Switch, Digital Phase Converter. etc

looking for some help with this.
i’m running a 3 phase combi wood machine on 220v 3phase through a digital phase converter. set up with lots of help from here a year or so ago.

problem is there is no start stop switch on the machine.
there is the option to wire a remote switch into the control circuit of the phase converter.
i’ve got this working with just a light switch today.
seems like i can’t use an NVR switch it seems because it needs current to it for relay to work, is that right?
and it can’t have any cos it comes after the phase converter. couldn’t leave the phase converter running all the time anyway.

also, the safety function of an NVR preventing machine from re-starting in the event of power-cut etc, isn’t needed cos that happens at the phase converter anyway

does that all sound right?
so am i just looking for a basic switch with safety styling?(very low current in control circuit)

thanks

You are correct – NVR is to protect against machines starting after a power supply cut . NVR is energised by supply to keep switch on – supply cut = switch off.
Safety/emergency off is what you need.

Sounds like you want to add start/stop buttons to the machine?

Most things are possible, it’s just a case of finding the correct parameters in the VFD.
If you’re just adding a single on/off switch, then there will be a parameter to prevent start up on power on. If the switch is on, then you’ll need to cycle it off/on for the VFD to start outputting power.

If you’re adding a push button start, and push button stop, then you’d normally use a NO (normally open) switch for the start, and a NC (normally closed) for the stop. For suitable switches, search ebay for “2 push button station” If you get one with an E-stop button, it gets wired just the same as a non-latching stop button, it’s just you have to release the button before things will re-start.

mc, yes that’s right, i want to add start/stop.
i have it functioning that way at present in fact, but just with a light switch. by this i mean one wire running out to switch from controller, switch completes circuit and wire runs back to controller. if i could find a suitably designed switch to use with this configuration it would be best. but it sounds like the NO, NC arrangment might need a circuit for start and one for stop? or is the function just mechanical in the switch mechanism?

and yes, i need the functionality of and NVR where start up on power on is not possible and requires cycling.
if only the manual wasn’t in such bad chinglish!

what are you using VFD to stand for btw?

i’ll have a look for those type of buttons, thanks

VFD = Variable Frequency Drive aka Inverter.

Start/Stop buttons use two separate circuits, although are typically done with just 3 wires. VFD control common for the inputs gets connected to both buttons, then separate wires back for the start/stop buttons to separate inputs.

What make/model do you have?

it’s a huanyang.
1 or 3 ph 220V to 3ph 380V.

at the moment i’m using the FOR(ward) and DCM terminals. so i would just also have a connection from the stop switch back to a 3d terminal and that would be it. sound easy enough. just need to get into the settings to make sure it’s going to work.

i had actually conceived of it as the DCM being the return leg of the circuit, not that i makes much difference, but is the DCM actually supplying the small operational current for the control circuit?

just to be sure, i can’t wire the NVR seitch i have for this use can i? it would need to have the 380v arriving at it?

http://www.jinlantrade.com/ebay/invertermanual.pdf

Page 37 (or 21 by adobe page numbering), shows a diagram of what you need. It’s wired slightly differently from what I posted above, and also has a reverse button, but just ignore the reverse button bit.

DCM depends on the inverter. Going by the fact it’s labelled as DCM, I’d assume it’s a common/0V return, with the inputs being pulled high internally, however it could be supplying 12 or 24VDC, and just the translation is poor. Checking the voltage between the DCM and an unconnected input would soon tell you though.

NVR switch won’t work. You could connect it before the VFD, however VFD’s generally don’t like getting their inputs turned on/off like that, and is not advisable. And putting it on the VFD output is a definite no, as that will most likely cause magic smoke release on the first use!

excellent. thanks a lot for your quality help.

yep, that’s the page i was looking at.
you mean the first diagram i’m guessing?
i don’t seem to have multifunction terminals labelled D1, D2 etc.

i don’t quite understand the function. seems like the NO and NC switches in series would do the job, with a manual reset on the stop, or with the start button closing the stop also if it’s open.
i guess that’s what you’e saying? the D3 terminal just serves as the return for the reverse signal circuit?

at the moment i’m essentially using it as in the second diagram, but without K2 switch.

Or is D3 a reset function? reset within the VFD?
not sure why i’d need that if the functionality is built into the switch?

Yes, the first diagram.
The D3 is used as the Stop control (it needs to be connected to DCM to allow the inverter to run). The benefit of that wiring method, is if the Stop circuit is open, then there is no connection available to the Run button.

If you look at page 11 (8 in adobe), it lists the alternative names for the labelled terminals. D1 = FWD, D2 = Rev, D3 = Reset.
That’s how they are configured by default, but they can be re-assigned to any of the available input options (look at the PD0044 section to see all the available options).

Reset is for clearing faults. You should not need it during normal operation, however it avoids the need to either power cycle the inverter, or find the reset option via the control panel (don’t mistake it for the factory reset, as that resets everything to default values!)

mc, i’m sure it was you who helped me with this unit before.

i feel like a right mug for not reading the manual properly, and it was the same last time!
thanks again for spending the time : )

so the ‘direction’ of the circuit: current flows from DCM to the others?.

hey mc, finally got round to installing Start/stop station today, and works exactly as described – ie works a treat!
i can see how the reset feature is handy too.
also managed to fit a good sized magnet to the back o it so i can move it about on the machine, no-where obvious to pu tit otherwise.
thanks again for your help
all the best to you