Help wiring 3phase machines with switches

[rorie]

Hi folks

I have picked up two machines (pillar drill and band saw) from a workshop. I have my 3phase converter (with 4 pin sockets) so i want to put a socket onto each of the machines so i can just hook them up when needed.

I have some photos and wiring diagrams for each one. I'd appreciate if someone could help

1) tell me if its possible to wire them up to just a socket, or if i need something extra to allow them to work with the switches?
2) If 1 is ok, how do i wire them?!

Pillar Drill

Band Saw

 

[brightspark]

if your not using a 3 phase contactor just buy a 4 pole rotary switch and wire it in direct from plug to switch to motor. keep it simple and cheap

 

[daleyd]

Looks to me like there is some contactors not shown on your drawings, without knowing how these are wired it's difficult to say if it's ok or not. They could well be ok but it would be prudent to check thoroughly and make sure your drawings match up to the hardware.

As bs said above, probably easier to use a rotary switch direct to motor, otherwise you'll need to delve a bit deeper. (You'll probably need to do this anyway to disconnect whatever else is/was there.)

 

[brightspark]

whats your converter rotary static or inverter and whats the voltage

 

[daleyd]

Also do you have a neutral? If not then some contactor coils may not work. (If they are 240 v coils they work between 1 phase and neutral, 440v ones will work between 2 phases - assuming your supply is 440v)

You'll want to know what voltage the coils are rated for before powering them on, otherwise the magic smoke may be released!!

 

[rorie]

hmm. The photos and wiring i have noted is what is on the machinery. I don't know what it was connected into before though!

I have a clarke converter like this one:

https://www.machinemart.co.uk/p/pc-...n8u29fybuF159HtcBEaUjcvnZEenAds8uWhoCarDw_wcB

Effectively i was hoping to wire it into a 3phase socket so that i could just plug it into the converter....

I can hook it up to the converter via a rotary switch, but i guess a rotary switch isn't ideal for this type of tools - i would ideally like to keep the switches which are on the machines just now. Is that possible?

 

[WorkshopChris]

From the looks of the wiring to the switches and no obvious signs of any contactors i wouldnt be surprised if they were last used with a VFD.
You will probably need two DOL Starters and overloads.

 

[daleyd]

It's possible, but you really need to try and identify all the components there already.

If the machinery had a neutral previously then you may be faced with a bit more work to make it functional as I don't "think" those Clarke converters will give you a neutral to use (that's only a semi educated guess though, someone else may confirm or deny this).

You could redo with new control gear which wouldn't be massively difficult. (Just seen Chris post above, that would be ideal)

 

[brightspark]

a couple of 415v dol starters will sort it simply enough. there about 30 quid each

 

[WorkshopChris]

a couple of 415v dol starters will sort it simply enough. there about 30 quid each

I have found the ones Toolstation stock to be about the best i can find price wise.

 

[brightspark]

simple to wire .3 wires in and 3 out to the motor. if your super safety conscious wire any safety switches through the contactor coil feed in starter . personaly I wouldn't bother unless your daft enough too put your fingers in when its turned on https://www.google.co.uk/?gws_rd=ssl#q=3+phase+dol+starter+wiring+diagram

 

[rorie]

Great thanks folks. I am happy enough going without the extra safety switches!

Are the switches i have just now not suitable for the task, or are they reliant on the contractor?

 

[WorkshopChris]

If you were to add new DOL starters you could those existing switches as remotes if they are in better position, but without a DOL unit or additional contactors they aren't much use to you.

PS i would double check all the existing wiring as it looks as if earth wires were used as switching wire in the photos you never know what else may of been played with.

 

[vwmark]

I have found the ones Toolstation stock to be about the best i can find price wise.

Just looked at the tool station dol. Do they have overloads in?

 

[brightspark]

the overloads are generaly sold separate as there diffrent amperages and fit in all the starters

 

[WorkshopChris]

No you need to select a overload to suit the motor FLC.

 

[vwmark]

Right - thought they were cheap. Thanks

 

[rorie]

Hi again - a simple question just to make sure i have this understood correctly:

I now have a DOL switch. I can wire this to my 3 phase plug, then to the motor?

What does the DOL switch do?! Why do i need a DOL rather than just a normal on/off switch?

 

[WorkshopChris]

If you use a DOL starter your supply goes in the top then the overload with the motor connected.Any limit switches, e stops, guards or remote switches also wire into this. The overload will protect the motor in the event of a fault.
Also in the event of a power failure the motor will not restart until you start it.
You could just use a 3 pole rotary isolator but the motor will not have any protection.

 

[brightspark]

Hi again - a simple question just to make sure i have this understood correctly:

I now have a DOL switch. I can wire this to my 3 phase plug, then to the motor?

What does the DOL switch do?! Why do i need a DOL rather than just a normal on/off switch?

direct online starter with overloads realy not needed unless the motor is left running unattended a triple pole on off switch will do and cheaper