Myford Industrial Stand Wiring

Hello all from a newbie Myford owner. I was wondering if someone could help me out with the standard wiring diagram from the industrial stand so i can wire up my single phase motor. the 4 wires white, green, red, blue. Any one have a diagram or such that may help. many thanks

The colour wires seem to indicate that it is for 3 Phase - ? Have not seen that colour combination for single phase even with reverse ? may be others have.

Hi Stephen,

Check your mail box.

I have a scaned copy of my Myford super 7 wiring diagram (single phase motor) I can send you.

Hi all and thanks for getting back to me..

This may help..

The Myford Super7B i purchased on eBay

Link is here **LINK**

It was supplied with a single phase Crompton 3/4hp motor as can be seen.. but having collected it it appears that it has only been wired up straight to mains with a 13amp cable and bypassing the stand all together.

i have the original myford book and the super 7 book but it does not appear to show any wiring from this type of stands swithgear... unless im reading it incorrectly.

I was not aware the myford industrial stand was wired for 3 phase.. clack of knowledge i guess but stands to reason it would be i suppose, and maybe as the motor was bypassed with a 13amp lead.. ? hmmm

I spoke with another chap who seemed to think that my wiring was single phase and i just needed the diagram, maybe he has made a mistake.. i dont know.... ?

It came with a diagram with what the original owner (who has unfortunately passed away) must of received when he purchased the lathe originally. but it is incorrect as when i have wired it by this to the 4 poles of my motor it just blew the 13amp fuse... Im was also told by the people who sold me it just afterwards that the info is incorrect... hence im stuck at present.

any help very welcomed.

Phil i have sent you an email

many thanks

Edited By Stephen Baxter 1 on 08/12/2013 17:32:22

Hi Stephen,

Back home now and access to my S7 manual. It shows wiring diagrams for 1 phase on the Santon reversing switch and both 1 & 3 phase on the Dewhurst drum type reversing switch. Only the 1 - phase diagrams show the 4 colours listed by you. The motor plate in diag. shows A1,A2,Z1,Z2. My motor has 4 terminals marked A1,A2,T2,T3. My notes show Z1=A1, Z2=A2,A1=T2,A2=T3. On the back of the non-industrial, folded and welded stand, there is a brown terminal block numbered 1 - 8.

MOTOR wiring:-

Mains Neutral goes to 3, Mains Live goes to 4. Blue wire from 5 to A! / T2. White wire from 6 to A1 / Z1. Green wire from 7 to A2 / T3. Red wire from 8 to Z2 / T2.

See next post.

Wiring post part 2.

TERMINAL BLOCK TO DEWHURST SWITCH:-

Black wire from block 3 to drum 3. Red from block 4 to drum 1. Black from block 5 to drum 5. Red from block 6 to drum 2. Black from block 7 to drum 7. Black fro block 8 to drum 6.

Wiring pt 3 - Correction to motor wiring:-

Red from block 8 to motor Z2 / A2.

Sumarise -

Drum - Block - Motor (in line as per diagram):-

7-7-T3, 6 -8 -A2, 5- 5-T2, 2 - 6 - A1.

Mains - Block - Drum:-

3 -3, 4 - 1.

Wiring Pt 4

Drum terminals 4 & 8 not used.

Block terminals 1 & 2 not used, in diagram but use say 1 for earth connection, not shown on diagram. Ensure you have a complete run of green and yellow striped earth wire from mains lead to block to motor casing, securely screwed-up tight. Also ensure that stand and lathe also connected. Beware, if you use cork washers under motor bolts to deaden vibration, you need to earth actual lathe, just in case....

Manual says "N.B. When a push button starter, with or without isolator, is fitted, the supply should be connected to it (or to the isolator), NOT to the terminal block."

Standard recommendation is to use a no-volt isolator for on/off and drum switch for merely reversing the motor.

As I dont have an isolator and just use the 3-pin socket switch, I cannot help with wiring in an isolator.

If you want, I will try to scan and send diagram to you. If the above connections fail to effect a reversal, you need to swap a pair of like wires to the motor, say A1 and A2 or T2 and T3.

If in any doubt obtain assistance of a qualified electrician as I cannot accept any responsibility for the previous posts.

HI Stephen,

my Super7B is mounted on the industrial stand, when I bought it some years ago I got in touch with Myfords who put me on to their electrical expert who assured me that the switch panel on the industrial stand cannot be adapted to single phase wiring, so I bypassed the panel and simply fitted a modern no volt on/off switch which has been working OK ever since,

regards

Peter

Stephen,

I have put a wiring diagram for single-phase Industrial stand in my albums. This was originally a large (Imperial equivalent to A3) sheet so ahd to be reduced.

Got it from Myford years ago.

Have an Industrial stand wired for single phase but would have to open it up to check the wiring, can't do that just now as can't get at it!

The wiring diagrams from the "normal" manuals will not help, they are for external switchgear only.

I'll try and put it here:

Edited By Robbo on 09/12/2013 10:09:16

Sorry i have been hard at work but thanks to all for the reply's and your help.
At present i have been unable to do much more until now but i am now getting back into it with the info i have received.

I have managed to probe 2 of the wires coming out of the stands motor wiring and have 240v on 2 wires and now have the original Myford pump running. I pre purchased a NVR switch a week ago as i thought i might not be able to wire it to the stand with the standard setup, but as it is at present i am still interested in what and how it has been wired, and if i can rewire it as it is, so we will see what happens..

I too have the Industrial Stand wired for 3-phase and intend to use a Single Phase motor with the aid of the Single Phase wiring diagram A7966 from Myford. I see two issues : firstly the Santon Rotary Switch SR127 which is needed for single phase reversing is not standard and no longer available, but this is solvable because Santon rotary switches are modular in design and dismantlable such that one can easily make up one's own single phase reversing rotary switch from Santon parts reorganised. Secondly, the standard 3 phase Crabtree circuit breaker has a 380-420v coil inside and my question if anyone can help please is is it necessary , possible, and practical to change the coil to a 220-240v for domestic single phase usage? The Myford A7966 does not address this coil voltage issue so is that an error or does it in fact not matter? Furthermore , I can get no information on this Crabtree circuit breaker from Myford and wonder if anyone knows what the model is - all I can see on the casing is "J.A.C." and below that "C.B." and below that "2". If this breaker can be used, does anyone know what the adjustable "Full Load Motor Amps" needs to be set to (choices are 1, 1.25, 1.5, 1.75, 2) as these amps seem very low unless one is supposed to read the figures multiplied by a factor of 10. Many thanks to anyone who can help. Adam

To Adam with his Crabtree circuit breaker( which I think will be a contactor) I don't think Crabtree are still around any more,but it was normal to be able to change over coils in the past. However, in some cases the coils can be modified so that it will operate on 240 volts, by carefully removing about a third of the turns of fine wire. The coils are impregnated with varnish and some need warming otherwise the wire breaks and the end is hard to find. If the coil former is bakalite type material it can be put in warm oven or over the lathe light, becareful with modern plastic as it soon melts and distorts. Measure the coil resistance then remove turns until you have a resistance of 57% of what you had initially. Assemble the contactor and give it a test, a trcky job but it can be done.Ted

To Adam with his Crabtree circuit breaker( which I think will be a contactor) I don't think Crabtree are still around any more,but it was normal to be able to change over coils in the past. However, in some cases the coils can be modified so that it will operate on 240 volts, by carefully removing about a third of the turns of fine wire. The coils are impregnated with varnish and some need warming otherwise the wire breaks and the end is hard to find. If the coil former is bakalite type material it can be put in warm oven or over the lathe light, becareful with modern plastic as it soon melts and distorts. Measure the coil resistance then remove turns until you have a resistance of 57% of what you had initially. Assemble the contactor and give it a test, a trcky job but it can be done.Ted

Hi Ted, thanks very much for your guidance on the coil. It does sound a one-way move that I would prefer to avoid - best result for me would be to swap a matching coil so that in the future if I needed 3 phase I could reverse that swap. I suppose, if it is as you imply necessary, in order to do that I need to find out exactly what coil size/spec I need and where a supplier of that coil is. If this is going to be very difficult and expensive would an easy and cheap way be to just purchase a different circuit coil contactor (?) that can do the same job but 220v? I will post some pics if I can as actually I know very little about what this item actually is or does! If you would be so kind as to have a look maybe you could educate me further! Many thanks, Adam

Hi Ted, Here is a photo , there are more in my album that you can view. What exactly is this big coil contactor (?) block on the right then, that has L1, L2, L3 inputs an A1, B1, C1 outputs, anyone?? Thanks, Adam

I suppose I can guess what it does (when correct voltage hits coil a magnetic force is created that pulls the contactor plates down into completing the circuit, and if voltage drops contact is broken?) but why is it necessary and useful and what do I do with the "full motor load" amp adjustment dial (top left) and indeed the red reset button (top right) that can be set for either Manual reset or Automatic reset (presumably set it for Auto reset unless I want to have to keep unscrewing the plate to get at it when required!). Any info much appreciated. Thanks, Adam

Hi Stephen,

I have just joined the forum.

Are you on the way to a solution or are you still looking?

I converted an industrial stand from 3 phase to single in 2011.

The Myford factory electrician told me I had to replace the Santon rotary switch with a rather expensive and ugly one from RS. This solution did not provide no voltage release.

I didn't want to change the external appearance of the front panel, so I did it by replacing the contactor. Worked our fairly inexpensive I think, doesn't load the Santon switch much and provides NVR.

I will add a wiring diagram if I can get "Albums" to work!

Hi Robert, I would be very keen to learn what contactor you used as a replacement. I have created my own Rotary switch from parts of old Santons and would now like to buy a contactor device (220-240v , 6amp fuse, auto reset fuse) with the same functions as the one in my photo (albeit single phase) so that I can just reroute existing wiring and so use the existing Start and Stop buttons. Please do let me know what you used! Adam