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caskwarrior
16th Jan 2017, 10:45 AM
Im now on the last stage of my Bridgeport project, and its the electricals, the previous owner has partially stripped them out, I am definitely down a few contactors amongst other things, Im not looking to do the electrical work myself, at least not without some serious research and supervision, but I am looking to get everything i need to at least keep the costs down as far as possible so I could really do with knowing what I am missing.

Although I have 3 phase available I have already got the mill running off a single phase VFD (So I can at least use the mill), but what I would Ideally like to do is:

1 Run only 3 phase to the mill cabinet
2 Take a single phase of that to the VFD (inside the cabinet)
3 Put a No-Volt release on the input power
4 Get the table X axis power feed working from the inbuilt transformer
5 Get some kind of DC power source inside the cabinet for running ESP microcontrollers and stepper motors (although most of the motors need 3A and the esp's much less so i guess at least two DC sources)

I do not have any kind of original Adcock and Shipley wiring diagram and would really appreciate a scan of one if possible, or even photos of anyones working setup as well as tips on sourcing any of this.
I thought I had hit a goldmine when I pulled a whole heap of contactors and another smaller VFD when I dismantled some food machinery in the scrapyard, turns out its all 110v. (photos included)

I would also appreciate info about the best and safest place in the circuit to have the NVR
366226366227366228366229366230
Stuff I got from the scrappy, its an Italian 1.5hp vfd plus a timer and some other stuff
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.RC.
16th Jan 2017, 11:27 AM
I think to do it properly you will need to for the control voltage reduce the voltage to 24V and get appropriate voltage contactors. A lot of machines do seem to use 110v for this though, but 24V would be safer.

Michael G
16th Jan 2017, 11:50 AM
Although I have 3 phase available I have already got the mill running off a single phase VFD (So I can at least use the mill), but what I would Ideally like to do is:

1 Run only 3 phase to the mill cabinet
2 Take a single phase of that to the VFD (inside the cabinet)
3 Put a No-Volt release on the input power
4 Get the table X axis power feed working from the inbuilt transformer
5 Get some kind of DC power source inside the cabinet for running ESP microcontrollers and stepper motors (although most of the motors need 3A and the esp's much less so i guess at least two DC sources)

1&2 I'm not sure what advantage you gain running 3 phase power to the machine and then only use a single phase of that. 3 phase to 3 phase VFD do exist, so if it is just for spindle speed, perhaps hunt up a second hand one of them.
3 A contactor will do that as will a VFD (one of the reasons these machines use contactors)
4&5 If you supply 3 phase you will also need a neutral to do that. Some three phase supplies don't have that (cheaper) as if just a motor is being run it should not be needed. Better check before you make too many plans around it.

As Richard says, 24V is considered a safe control voltage although contactors exist for a range of voltages - my lathe uses 415V for control circuitry.

Just to throw further confusion into your thoughts, why do you think a VFD is necessary? They are nice certainly for speed control but Bridgeports have been used for years without them so I would not call it essential. I have two VFD's on machines and all they do is convert single phase to 3 phase - cheaper than changing the motor over.

Michael

caskwarrior
16th Jan 2017, 01:38 PM
Thanks for the replies, to clear a couple of things up, Im currently using the VFD I have on hand to drive the mill (single phase to 3 phase) because I don't have most of the original electronics, also I only have 3 phase power near the machine and I don't really want to have to run single phase out to it from the box. So i figured I could make it nice and self contained, I may run it without the VFD although I do find the higher top speed useful. All the wiring in the area I am in carries neutral so thats nice.

When I said no-volt release I guess what i more meant was emergency stop as I currently rely on the vfd remote control for that, and i don't really consider it to be safe. The original fwd/rev/off switch up on the head has also been deleted which would make not using the vfd a hassle as i would have to source one.

Thanks so much for the useful information, I will confirm what the control voltage was originally as soon as i get back down to the factory.

Regards - Ralph

Keith_W
18th Jan 2017, 06:22 AM
Hi Caskwarrior,
You can use the VSD as you have Neutral in the 3 Phase Outlet, you just use 1 Phase + Neutral & Earth.
The way you configure the Control Circuit will allow for theEmergency Stop to do its function, if you just want to cut all power to theMill install a main Contactor after the Main Isolation Switch, so when the EmergencyStop is activated all power is removed.
If the VSD has the Safe Off feature you could also use thatas a method.
You mentioned that it’s in a Factory, if there are Employeesgoing to be using the Mill as well you need to configure the Control Circuit soit meets Australian Standards for both Safety and Wiring.
Getting a Contractor who is competent in these areas maybeyour best option.

Keith_W.

eskimo
19th Jan 2017, 08:14 AM
my lathe uses 415V for control circuitry.



you dont need to run a neutral wire to the machine.

its a silly idea isnt it?...much better to have 24v control, with -24 earthed for ease of fault finding


Oh and Ralph...your motor is or can be wired for delta?

Keith_W
19th Jan 2017, 08:58 AM
If you look at the Dinverter its a Single Phase Unit, It has a Neutral input, yes you could run a floating Neutral but when there is a Neutral available at the Outlet it would make sense to use it, not such a "silly idea isnt it".
The control voltage can be what ever you like and 24V AC or DC is a better option.

eskimo
19th Jan 2017, 09:11 AM
If you look at the Dinverter its a Single Phase Unit, It has a Neutral input, yes you could run a floating Neutral but when there is a Neutral available at the Outlet it would make sense to use it, not such a "silly idea isnt it".
The control voltage can be what ever you like and 24V AC or DC is a better option.


Kieth..i refer to machines that have 415V control circiuts as to it being silly ...why should'nt it be 24V AC...makes life simpler.
Yes I know they use 415V in certain circumstances but is it really neccessary on simple machines. Makes fault finding easier and less dangerous if it was 24VAC
and yes 415V doesnt need extra cost for a tranny...but again for that small extra cost you have a simpler 24V control circuit

adding or making the control circuit DC of a straight forward 415V machine (or doesnt have a PCB's or similar) is just as silly! IMO :D