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Wiring Schematics for Bridgeport

Mark Leigh

Stainless
Joined
Jan 8, 2008
Location
Merced, Calif
Hi all, where can I find a wiring diagram for a Bridgeport built by Textron. On the electrical panel box attatched to the machine the nameplate says Drawing No. WD153D


I am firing up the mill and finding that in high speed the contactor will pop out and stop the motor about 1 minute into running it.

I am confused about the control panel mounted down low, do I have to have the toggle switches in a certain position to run the head or do I just use the hi/low selector switch on the head motor.

I have read that there's protection circuits to stop the head if the x power feed is running and the head stops, or vice versa ??

The machine is a serial number 402730485W Order No 85309 thanks for all replies.
 
The machine is a serial number 402730485W Order No 85309

That's not a knee mill SN. Is this a CNC?

Chances are, the wrong heater is in the contactor. Probably sold as a 440 VAC machine and then changed to 220. The heaters are the wrong size for the mill. If this is a standard knee mill, the contactor box on the side was an option added mostly for higher voltage machines. If you're running on 220 VAC 3 phase, you can remove the box and use the current wiring diagrams.
JR
 
Hi JR, thanks for the reply, here's some pics. It is a standard looking knee mill, I'm told BP's were made over at Textron for a few years ? The numbers don't show up on any lists I have found to date . The large electrical box on the side also houses the drive for the DC motor on the X axis I believe,



bridgeport11.jpg




bridgeport12.jpg



bridgeport13.jpg



bridgeport14.jpg



bridgeport15.jpg




bridgeport10.jpg






It is wired at the T leads for 230 volts, we were running it on 230 temporarily. My questions are what size heaters should I change out to ?

Also I need to trouble shoot the DC drive on the X axis as it won't start and the hi / low lever will not park in the detent for high speed, I am thinking the vari drive is dusty from sitting in a fiberglass manufacturing facility for years --------- Any ideas on that are also appreciated . Thanks
 
OK, a British made BP. BPs were being made in Leicester before Textron.

That machine was wired for 380-440. Are you trying to run from 220? Have the motor leads been changes?
Those are not US made contactors. Don't know how to calculate the heater size on them or if you can get.
The DC motor controler for the 6F drive is probably in that cabinet.

Like I said, if you're going to run your mill on 220, you can eliminate the large cabinet. There are a lot of things that you need to do before.
JR
 
Yes the drive for the 6 F is in the bottom of the cabinet. Yes the motor leads are on low voltage scale on nameplate. I would throw the cabinet away if it wasn't for the 6f drive I guess. I will see if I can get a local electrical shop to help me with the heaters I guess.
 
Mark

With a Leicester UK Textron build plate that will have an Adcock Shipley build/serial number not a Bridgeport USA one. Yours translates to a machine built in April 1985.
Cabinet layout looks to be very similar to the normal UK / European set-up rather than the common US versions which frequently lack contactors for drive selection, relying on the forward-off-reverse (often marked high-off-low) drum switch up on the head.

Assuming it is basically UK/Euro I have a scan of wiring diagram drawing number WD145/D which is, I think, mid 1970's vintage and probably has the information to directly fit any UK/Euro machine up to around 1980 ish. PM me if you'd like it. I don't think there will be any significant functional difference between that one and the correct one for yours. Pretty sure the fuse layouts and transformer details will vary but that's more cosmetic. Power feed drive box on yours is most likely Bridgeport branded rather than the Ericcson unit commonly found over here. You can download the circuits for those direct from Hardinge.

There are issues with the contacts in those overload current units. Time for a good clean. Also verify that the auto / manual reset adjustment is correctly set and all behaves well. Gremlins in there can drive you nuts!

If your low level control box is to UK norm then toggle switch(es) down selects which drives will come up when the go button is pressed. Contactors should be wired via the head motor contactor so that needs to run before anything else will go. For test purposes the forward-off-reverse (high-off-low) switch on the head can be set to off isolating the head motor so nothing is spinning. You shouldn't use a UK spec head switch to stop and start the motor. The contacts aren't up to the job and its the wrong style of switch anyway being a disconnector rated to carry the current load when set rather than a true switch which is rated to break, or make, full load current.

If its been in a fibreglass factory a good scrub is essential. Be careful as short ends of fibre are darn itchy. The detent plate on the high-low lever is adjustable for correct parking position without hasty noises of drive dogs ratcheting past each other trying to engage when they shouldn't. A careful look at the parts book will allow you to figure out the adjustment. Most likely the plunger is gunged up and not moving freely or the recess itself is full of crud (like wot mine was).

Clive

PS Unwilling though I am to cross keyboards with JRIowa throwing the cabinet away is a bad idea unless you want to re-wire from scratch. Might be just about acceptable if you were planning to do a simple VFD drive to the head set-up but otherwise its much easier to sort what's there. I took a good look at starting over and VFD'ing mine but figured the gain wasn't worth the candle and went RPC then whole shop digital.
 
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Unwilling though I am to cross keyboards with JRIowa throwing the cabinet away is a bad idea unless you want to re-wire from scratch.

Clive, Why should you be any different than others? Go ahead and beat me up ;) I like pain, that's why I work here.
For me, it would be faster and easier to rewire the machine. The only things that I'd keep from the box are the 6F control and the transformer for it. Just me, I hate those big, ugley boxes. If Mark hasn't changed the motor leads, there's another area that needs to be looked at.

I thought that it was an 85 machine. I didn't remember the code for sure. I knew that it couldn't be much older, Emerson (the mothership) didn't buy US Motors much before that.
JR
 
Thanks for the info so far guys. The DC motor controller is a ERSKINE Systems LTD unit--- It may be in working order, I need to go back and check it out with the right toggle switch in the right place --------------

Clive, thank you very much for the e mail with the electrical drawings !!!!!!!!!!
 
Mark.
Glad the wiring diagram got thu'. Didn't recall it was 5.4 meg file until after I sent it. Gawd knows why its so big. Acrobat Pro will pull it down to under 200 K but doesn't print well with some lines and text indistinct.
Yup Erskine is the standard controller over here, dunno why I put Ericcson before. I guess they are right memory is the first thing to go!

JR
Although I like the full on control box as, objectively its the right, full on engineered, way to do the job duplicating from scratch would be a hard row to hoe. When I set up a VFR drive on friend Johns manual feed Bridgeport mounting the VFD on the side of the step-pulley J-head took longer than wiring. Heck longest part of the job was driving the 20 miles from my shop to his to deliver VFD and custom bracket.

However removing the big box is a whole 'nother thing. Especially if you don't have suitable parts to hand, or at least access to a supplier. Ten times the trouble if you've not done it before.

For starters you have to find something to house the transformer, power drive box and fuses. Twenty or there-abouts wires on transformer and drive box too. Which have to be undone and reconnected to get outside the box. Keeping them straight and re-hooked right at both ends isn't exactly a walk in the park. Going USA simple on the head with a simple head mounted switch to control the motor means you hafta find a drum switch and the housing as the standard Brit spec cam switch will soon die. Cam switch housing is too small for a drum to be straight replacement and even the tapped holes won't line up. Then you have to find suitable switches to control the power feed, coolant pump etc. Are you going to at least nod to the 'elfins and use an NVR switch on the power in? Another thing to source and find a place for. Better do a wiring diagram too. 'cos you won't remember where it all goes! And if it doesn't work you get to figure it all out yourself. (It'll be something silly, always is.).

Aaaargh!

Not that I'm frightened of wiring but sometimes life is too short. At least with factory you have a nice picture of how everything is supposed to go. Objectively best way is to spend £100 to £200 ish to replace all the contactors, switches and fuse gear with nice new stuff which will just work for the next couple of decades. DIN rail mounted contactors and fuse carriers so you don't hafta curse fit umpteen "can't quite get straight on to them" screws. Far better than fixing, patching and making old stuff do for a few more years. Like we all do. I'm as bad even tho' I know fixing'n fiddling adds up to lots longer than simply slotting new stuff in. I guess its 'cos its cheaper.

Clive
 
Clive,

On this side of the pond, most of the stuff in the control box is not required unless you have 440 VAC service or higher. On a 220 VAC service, all that is used is the drum switch on the side of the head. No need for starter relays and such.

I'd have to look at the transformer taps, but most of the 6F and 8F DC drives were designed to run from 110-120 VAC. Even if the UK version was designed to run on 220 VAC, a simple step down transformer and the drive in a 6 X 6 NEMA 1 box on the back of the mill looks so much cleaner. That's less than $50. The 6F drives are problematic anyway. A rebuilt drive board is some where around $150 exchange. For about the same money, you can purchase a new drive. For a little more, you can get a Minarik.
JR
 
The only place that I know of.
BptParts.com: Bridgeport Machine & CNC Machine Replacement Parts

Or, go to something like this from Polyspeed for $150
OC1-25

Or, go to a Minarik drive for about $300
Minarik Drives your source for AC and DC Drives

Mark,
You must check the motor leads to see what voltage your motor is wired for. If you are going to run that mill on 220 VAC 3 phase, the motor leads need to be connected as the "low voltage" diagram shows on the motor plate. By the description on the machine data plate, this machine was wired for higher voltage. If you don't know how to check or change the voltage connections on the machine, you'll be burning up more than a 6F board.
JR
 
Just to add my two pence worth I have stripped all the contactors out of my British built BP and run the motor directly from an invertor (VFD ? ). The Erskinne unit driving the X axis drive -powered at 110VAC from the transformer- gave up the ghost and let out its smoke and I found it impossible to either repair it myself (No wiring digrams) or find anyone to repair it. Having said that I did notice someone selling exchange boards on ebay some time ago. I went with a chinese x axis drive which works well for me.
It is kind of strange to wonder how a British machine presumably built under licence from Bridgeport ends up being exported to the Sates
 
The only place that I know of.
BptParts.com: Bridgeport Machine & CNC Machine Replacement Parts

Or, go to something like this from Polyspeed for $150
OC1-25

Or, go to a Minarik drive for about $300
Minarik Drives your source for AC and DC Drives

Mark,
You must check the motor leads to see what voltage your motor is wired for. If you are going to run that mill on 220 VAC 3 phase, the motor leads need to be connected as the "low voltage" diagram shows on the motor plate. By the description on the machine data plate, this machine was wired for higher voltage. If you don't know how to check or change the voltage connections on the machine, you'll be burning up more than a 6F board.
JR

Thanks for that info , I checked the motor T leads and it is wired like the low voltage diagram.
 
Update, I can get it to run but it shuts off unexpectedly. I then found the stop button wasn't working on the lower control panel. I also found that the #3 red wire was loose and laying in the box. I don't know where the #3 wire is supposed to land and the info I have read through doesn't cover it , any ideas ??
 
Mark

Is the loose #3 wire in the big box on the side or in the control station on the knee?
If no answer surfaces before the week-end I'll open mine up and see what's in there. As I recall matters mine still has all the original number sleeves on the wiring.
Non working stop switch on the control station suggests that someone has been playing as those switches are normally uber reliable.
Although the big circuit diagram looks complex its actually quite simple in concept so once you get your head round where stuff goes in the box troubleshooting is no great problem.

Essentially the stop side is just a string of normally shut switches, overloads and push button, in the line between the transformer high side output (110 V on mine) and the coil hold-on contacts on the contactor. Any problems in the string will shut everything down. When I had the intermittent shut-off problem it was either dirty contacts or bad setting of the manual / auto reset mechanics in one overload relay. When Mike-the-pilot had it it was a combination of a loose wire on the stop switch and rotary phase converter gremlins.

Clive
 
Thanks Clive------- it is in the small control box under the knee. One of the red wires in there. Thanks for the info, I will look at it again today. The stop switch is missing the red mushroom head so it may be damaged internally too ?
 
Mark

10.15 pm and I'm not getting anything I should be doing done so I unbuttoned the box a couple of hours early.

Most of the wires, all the ones we are interested in are red and nearly all the marker sleeves are there.

Red #3 goes to one side of the spindle power toggle switch, leftmost on the box but S3 on the wiring diagram you have. That terminal is daisy chained on to one side of the other toggle switches aux head S2, long feed S4, coolant pump S1. My #3 wire corresponds to LL3 feed from fuse SFU2 to toggle switches on the diagram. Wires on other sides of toggle switches are marked #6, #7, #0 and #1 in same order.

Stop button "feed" wire sleeve is #T, other terminal goes to one side of the start button and daisy chains into the wiring back to the big box. No number sleeves on either wire in the knee mounted box on mine but clearly this would run to the "keep alive" contacts connecting to the contactor coils. Corresponds to LL1 feed from fuse SFU1 on the diagram coming down through the overloads and the stop button. Wire on t'other start button terminal is sleeved #8 and runs back into the big box to daisy chain the contactor coil connectors to provide the power to initially energise the selected contactor coils(s) turning things on so the keep alive contacts can take over.

As that wiring diagram is a PDF it should be no trouble to blow up and print the appropriate section large enough to annotate then its just a matter of probing with your meter set to Ω and ticking off the good circuits, fixing as you go. Probably easiest to hook onto the start button terminals and verify feed from the two fuses (with appropriate switch settings) and work outwards from the knee box. My own print out has all the wires in that section ticked. An extra long meter lead with a good clip on it helps when the wire has an end in each box. Note that my wiring sleeve numbers are very different from those on the diagram. For example my #8 running from start button to contactor coils would be #1 if it followed the diagram.

Hope this helps. Don't need the machine till Monday so I'll leave it open if you need more.

Can fire up the digicam for picture(s) if need be.

Clive
 
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Maybe someone else noticed this and replied, but I just skimmed the posts.

This machine doesn't have heating elements in the thermal switch in the American way. The Europeans (and most of the rest of the world) did it differently, and more sensibly. Your thermal switch is adjustable and is shown clearly in photos 2 and 5. The dial, the adjustable part, says amps on it- to increase the setting turn it to a slightly higher number and see if that makes a difference. The reset button is that hex shaped thing right beside it. Loose terminations on either side of the thermal can also make it trip early.

Neil
 








 
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