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Won't fit?I have literally just realised something very stupid I’ve done. See if you can spot the issue
Won't fit?I have literally just realised something very stupid I’ve done. See if you can spot the issue
No. The three prongs connect to the backbox socket, without these in nothing is powered up. That’s fine If I program it right but i cannot then change any program settings without putting a direct feed to the VFDWon't fit?
So I had a look at that and it mostly makes sense. I did however look at my VFD before doing anything else after reading this.You need to think about safety, and you definitely need to implement some NVR function. I believe there are a couple of interlock micoswitches, 'end guard' and 'lock'. If your spindle switch is latching then you don't necessarily want the spindle to fire up if the interlock is closed...the correct operation would be to return spindle control to off before spindle can be restarted.
This NVR will also allow you to 'kill' power to the VFD should it malfunction. The attached schematic is one I devised for my M300 - it's a little more complex than you need, but you can see the NVR implemented as a 3-phase contactor K1, and you can see two interlock switches in series with the coil, 'gear cover' (the change wheel cover) and 'mushroom' (the emergency stop button), triggering either of these will open the contactor and remove power to the VFD, power can only be reinstated once the spindle direction/run lever has been returned to neutral.
Yes providing it functions like that with your actual lathe controls (latched) - as you're probably finding out, it's a good idea to get the VFD settings and wiring figured out before final installation. What happens at power on - can you configure it so that it doesn't start up if left with switches in spindle run position - looks like P65 could be configured to power up safely.With the E stop pushed whilst in operation you can’t just undo the E stop for it to operate again. Need to turn it off and back on again on the lever. So as far as I can see that covers what yourself saying.
It would appear pretty normal that the E-STOP function is a coasting stop. You';; find the coating stop is dependent on the inertia of your chuck/workpiece.The only thing with the E stop is that I cannot for the life of me work out how to stop it quickly.
Yes that's it, it won't start until the lever is back to the off position then back on. I will put a board mounted E stop on and I need to look at some idea's for a foot lever maybe. I will do it after dinnerYes providing it functions like that with your actual lathe controls (latched) - as you're probably finding out, it's a good idea to get the VFD settings and wiring figured out before final installation. What happens at power on - can you configure it so that it doesn't start up if left with switches in spindle run position - looks like P65 could be configured to power up safely.
It would appear pretty normal that the E-STOP function is a coasting stop. You';; find the coating stop is dependent on the inertia of your chuck/workpiece.
You used to find foot levers / Lunn bars on everything at one point. Not seen one in years. Tried to find a foot emergency stop for my pillar drill a number of years back and gave up in the end.Yes that's it, it won't start until the lever is back to the off position then back on. I will put a board mounted E stop on and I need to look at some idea's for a foot lever maybe. I will do it after dinner
I hate to be complimentary to taffy but he’s a proper electrical engineerA simple switch open/close is all it takes to stop and then reverse the vsd. Two wires to the switch on the lathe.
One thing I found is that there’s and emergency stop function in the VFD
P53 preset 19 that sets the connection x3 to the E stop.
Your VFD has the removable keypad so mount that on the other side?No. The three prongs connect to the backbox socket, without these in nothing is powered up. That’s fine If I program it right but i cannot then change any program settings without putting a direct feed to the VFD
Most vfd's can be configured whether they start or not after power loss. The Invertek support explained to me that E stop on a vfd can only coast, as its possible the vfd being faulty - so it should not apply power to stop quicker. In a non- faulty situation, you just want easy access to the start/stop control for the quickest possible stop.Yes that's it, it won't start until the lever is back to the off position then back on. I will put a board mounted E stop on and I need to look at some idea's for a foot lever maybe.
So should the VFD suffer a fault then your emergency stop may fail to operate which is far from an ideal situation.
VFDs are used in industry day in, day out. Are there any published guidelines on best practice relating to this topic? I would have thought that the E-stop should always be within the control circuitry of the VFD. The VFD itself will have a (lockable) isolator upstream of it.
Out of interest, are you aware of any cases of this? What would you estimate the chances are of the VFD developing any fault? Of all the faults a VFD might develop, what proportion of them are likely to result in it being unresposive to its inputs? Let's put a number on it and say 1 in 10,000. Now, what are the chances of a mechanical fault in the emergency stop button itself?
If the vfd faults it's mostly a complete failureThe problem with this is that you are relying on the electronics in the VFD for your emergency stop to function.
So should the VFD suffer a fault then your emergency stop may fail to operate which is far from an ideal situation.
...however I do have copies of the relevant regulations...
That's not true, the input caps are sufficient to provide enough power for the VFD to perform controlled braking when supply is disconnected.Switching off the supply to the VFD will not do that as it removes all possibility of electronic braking.