SB Turnado wiring with Furnas control box

Bear with me guys and be kind - I ain't THAT dumb ('cause all smart people say "ain't", right?) but I'm a bit perplexed here - a common condition according to my fiancee...but she said YES so joke's on her, eh?

This is a '60s 17" SB Turnado with a Furnas box like this on the back. Clearly all this goes to the motor so what I need to know is where to attach my 4 wires in my power cord?

IIRC this machine "idles" the motor at all times and then engages the headstock as called upon, if that matters. This is one of the "good" Turnados made in IN, not the French electromagnetic whatchamacallits.

I see the ground up top, but definitely not certain on the 3 legs? Based solely upon loose screws I see one connection lower right (finger) and two matching up top LEFT and RIGHT of the green. But is that correct? Or should I be connecting at the black box up top?

Also I'm 99% this is already wired for 220 but can anyone tell?

There's no schematic on the outside or inside of the box but I did find this paperwork in the sheetmetal enclosure.

I'm grateful for any advice - I figure I might as well make the best of this virus downtime and get this machine under power! I saw the machine under power when I purchased it (so it works) from a trade school, but I'm embarrassed to say for how long it's sat here (years) waiting for nothing but a power cord....sad kinda.

D60 said:

Bear with me guys and be kind - I ain't THAT dumb ('cause all smart people say "ain't", right?) but I'm a bit perplexed here - a common condition according to my fiancee...but she said YES so joke's on her, eh?

This is a '60s 17" SB Turnado with a Furnas box like this on the back. Clearly all this goes to the motor so what I need to know is where to attach my 4 wires in my power cord?

IIRC this machine "idles" the motor at all times and then engages the headstock as called upon, if that matters. This is one of the "good" Turnados made in IN, not the French electromagnetic whatchamacallits.

I see the ground up top, but definitely not certain on the 3 legs? Based solely upon loose screws I see one connection lower right (finger) and two matching up top LEFT and RIGHT of the green. But is that correct? Or should I be connecting at the black box up top?

Also I'm 99% this is already wired for 220 but can anyone tell?



There's no schematic on the outside or inside of the box but I did find this paperwork in the sheetmetal enclosure.

I'm grateful for any advice - I figure I might as well make the best of this virus downtime and get this machine under power! I saw the machine under power when I purchased it (so it works) from a trade school, but I'm embarrassed to say for how long it's sat here (years) waiting for nothing but a power cord....sad kinda.

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This picture is from a little newer panel off a TURNADO. The line wires were hooked up to the forward contacter (see the wires that were cut). I don’t know for sure if yours was wired that way, but...
To make sure what voltage it is wired for, check the motor, it is a 2 speed, single voltage motor.
Ted

You can trace the wires from the primary of the control transformer back to where there are connection points.
That will give you two hot wires. Also trace back to where the fuse is connected.
A ground wire is not sweat. Just probably nearby the first two hots.

Look for the screws with excessively worn slots.

From the picture I would guess the upper right contactor.

D60 said:

Bear with me guys and be kind - I ain't THAT dumb ('cause all smart people say "ain't", right?) but I'm a bit perplexed here - a common condition according to my fiancee...but she said YES so joke's on her, eh?

This is a '60s 17" SB Turnado with a Furnas box like this on the back. Clearly all this goes to the motor so what I need to know is where to attach my 4 wires in my power cord?

IIRC this machine "idles" the motor at all times and then engages the headstock as called upon, if that matters. This is one of the "good" Turnados made in IN, not the French electromagnetic whatchamacallits.

I see the ground up top, but definitely not certain on the 3 legs? Based solely upon loose screws I see one connection lower right (finger) and two matching up top LEFT and RIGHT of the green. But is that correct? Or should I be connecting at the black box up top?

Also I'm 99% this is already wired for 220 but can anyone tell?

There's no schematic on the outside or inside of the box but I did find this paperwork in the sheetmetal enclosure.

I'm grateful for any advice - I figure I might as well make the best of this virus downtime and get this machine under power! I saw the machine under power when I purchased it (so it works) from a trade school, but I'm embarrassed to say for how long it's sat here (years) waiting for nothing but a power cord....sad kinda.

Click to expand...

This looks like a fun circuit! Where do the red wires go at top corner? To the motor? I believe what you're pointing to look to be aux contacts, used for interlocking or seal in circuits. The transformer at the top provides power for the control circuit. The contactors are marked forward/reverse and slow/fast for two speed. There is also a mechanical interlock "K" to prevent energizing both relays. So I'm guessing the top relays are energized to set the direction and then either of the two lower would be energized to set speed. They would all be electrically interlocked so you can't mess up but that's not the issue here. The three phase power to the motor would probably attach at the bottom of either the slow or fast relays. I see overloads there. (white push buttons. Check everywhere for screws loose or marks as mentioned. Post a pic of the bottom is possible.

You are all saints, thank you for your time! The red wires go into conduit and into the headstock, so 99% I'd say those are controls.

At the bottom black wires exit to where the motor would live.

However, maybe this marking answers everything I'd need - there's a "B" "W" and "R" here, this is the top left set of connections

^^alright that was it and if you look carefully at the gold hold-downs they are actually stamped "L1" etc (L2 is missing)

Now I just gotta figure out these spindle speed controls - they're a little weird!

Only three wires to the motor? Two speed I’d expect more

Looks like more than three wires.

Charlesc said:

Only three wires to the motor? Two speed I’d expect more

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Yeah if you look at the second photo in Post #5, the red wires exiting the upper left of the box into the conduit..........looks like probably 6 wires (edit: disregard, I'm a moron). Both speeds do work, although my 7.5hp RPC does seem to strain a noticeable bit to start the 7.5hp lathe motor in high (doesn't seem to have much trouble with low). But of course that's NOTHING to do with the machine itself.

This does idle once running....with a "clutch/brake" lever, so once you've got it going you're not actually starting the motor as much as other machines - - unless of course you want to switch to the other speed and/or reverse direction.

I haven't been brave enough to see if I can just go switch between high and low while running - - so far I've always pressed "off" then select the other speed. I imagine it either should work or should somehow prevent it (ie be idiot proof). I have to complete a particular job and then maybe I'll get more brave when I could theoretically afford some down time if something goes awry. Truthfully I'll probably never need high as low goes to 525 rpm I think it is and this is my "bigger" lathe for "bigger" work.

Regardless I appreciate all who posted and helped.

edit: I apologize! It's the black wires at the bottom actually going to the motor and it does look like only three or four (I wasn't thinking straight earlier, sorry!). I've since got it pushed back against the wall so I can't easily open that box again to verify.

D60 said:

(edit: disregard, I'm a moron).

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One mistake reading a 2d picture of wires on top of themselves does not make somebody a moron.

OK I was expecting six.

Post #5 lower left in first picture. More than three black wires.

rons said:

One mistake reading a 2d picture of wires on top of themselves does not make somebody a moron.

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Not according to SWMBO! Ok, ok just kidding.

Anyway, I've been making chips with this machine. Appreciate all at PM who helped or replied.

I wish I had the square footage to just leave my machine(s) in the middle of the floor to where you can walk around them, but this really needed to wind up in a corner. Sooo....I cut myself an access in the wall for the thru-spindle. My other lathe (LeBlond) only has an 1.5" thru spindle so I've already taken advantage of the 2-9/16" on this machine.

Also, I'm presently working on a patent for this super high tech LPD (er that's Lathe Portability Device), so no one copy me!

Oh, and once I shifted my thinking and realized I had to look for which COLORS align on the spindle speed dials, that all became clear. Never before needed to use colors for, well, anything on a headstock before so that just required a mental shift. Would suck to be color blind and run this, kinda like a Tekonsha Voyager trailer brake controller

D60 said:

Sooo....I cut myself an access in the wall for the thru-spindle. My other lathe (LeBlond) only has an 1.5" thru spindle so I've already taken advantage of the 2-9/16" on this machine.

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You have a mailbox slot as well. From the outside it probably looks like the end of a howitzer.