Is there an easy way to change output from 220 to 440V on the MEP804B

[Rik]

I have an MEP804B Genset. I have some items at my shop wired for 220v 3PH and some items wired for 440v 3PH. When I need to switch between the outputs I have to open the panel door, remove the 12 nuts on the panel plate and change it's position and rear attach 6 nuts and reassemble the protective plastic plate and so forth each time.

Is there possibly a way that I can wire a switch that I can merely flip/rotate/move to make the output switch between the 220V to 440V easily and quickly?


Thanks

 

[Scoobyshep]

There are switches made for that, it takes some work . Keep in mind this makes things more difficult for keeping 220 and 480 seperate

What kind of loads are you running? It might be better to set up a transformer

 

[Rik]

There are switches made for that, it takes some work . Keep in mind this makes things more difficult for keeping 220 and 480 seperate

What kind of loads are you running? It might be better to set up a transformer

The largest draw I run is the air compressor on the 220, but other the start it's not drawing that large of a load. Possibly 30%. 440 is just a mill and the load doesn't really show on the meter as it's just a 1hp motor.

Thing is, only one mill is 440, the other mill/lathe/bandsaw/AC and such that I have are all 220 and I've unsuccessfully tried to switch the one mill to 220 so this is way I want to make it easier as I have to switch the Gen to 440 every time I jump from the lathe to the mill and back to the lathe.

 

[Scoobyshep]

If the 1 hp mill is the only thing running at 440, just get a transformer and step the voltage up

 

[Rik]

If the 1 hp mill is the only thing running at 440, just get a transformer and step the voltage up

That's a lot more $ and work than a switch

 

[2Pbfeet]

That's a lot more $ and work than a switch

You've probably considered this, but why not replace the the motor, or possibly adjust the internal wiring to support 220V? 1HP is not usually an expensive motor compared to some of the possible switching solutions, unless it is an unusual rpm. A lot of the Bridgeports came 450/230V.

All the best,

2Pbfeet

 

[Rik]

You've probably considered this, but why not replace the the motor, or possibly adjust the internal wiring to support 220V? 1HP is not usually an expensive motor compared to some of the possible switching solutions, unless it is an unusual rpm. A lot of the Bridgeports came 450/230V.

All the best,

2Pbfeet

It's a Bridgeport Series II and there's more to the mill than just the 1HP (could be 2hp come to think about it) motor as there's a large electrical panel on these machines and they are using the 440 wiring in more places than just the motor. Else, that'd be a great idea.

 

[Scoobyshep]

That's a lot more $ and work than a switch

Upfront yes, the labor involved with switching back and forth (or the inevitable accident of wrong voltage) to me would be worth the investment.

On another note
The last machine in had to convert was motors and power supplies. It wasnt too difficult

 

[G744]

3PH Voltages 208, 230, and 480 have been standard for over half a century now...

110, 220, and 440 are long gone, as well as 416.

 

[peapvp]

It's a Bridgeport Series II and there's more to the mill than just the 1HP (could be 2hp come to think about it) motor as there's a large electrical panel on these machines and they are using the 440 wiring in more places than just the motor. Else, that'd be a great idea.

is this your Bridgeport II ?

If so, then Transformers T1 and T2 just need to re jumped for either 208 or 230 and so does the spindle motor.

It’s fully explained in the manual starting on page 3-4
Some fuses have to be exchanged to higher current ratings for the lower voltage

 

[peapvp]

3PH Voltages 208, 230, and 480 have been standard for over half a century now...

110, 220, and 440 are long gone, as well as 416.

Normally the lower voltage rating dictates the higher voltage rating
It’s
208 / 416
230 / 460
240 / 480

 

[Scoobyshep]

3PH Voltages 208, 230, and 480 have been standard for over half a century now...

110, 220, and 440 are long gone, as well as 416.

416 is common in plants that have 4160 coming in, 230 as well for 2300. Think big industrial like paper mills.

That being said there are tolerances, some equipment is made for 480 but is rated at 460 which makes it useable between 440 and 480.

My last plant had 346\600 coming in. Current facility is closer to 500v and the drives are running 650 DC.


Point being standards aren't as standard as you think.

 

[peapvp]

416 is common in plants that have 4160 coming in, 230 as well for 2300. Think big industrial like paper mills.

That being said there are tolerances, some equipment is made for 480 but is rated at 460 which makes it useable between 440 and 480.

My last plant had 346\600 coming in. Current facility is closer to 500v and the drives are running 650 DC.


Point being standards aren't as standard as you think.

I was talking about Motor ratings or Genset heads.
Since all 6 windings are normally equal

we require all our customers to install step down transformers from 480 to 440 on our equipment for a variety of reasons and encourage them to buy the 208/230 Volt units rather then the 440 V units

 

[2Pbfeet]

Here's a Bridgeport II schematic. As @peapvp points out, it looks set up to convert;
http://igor.chudov.com/projects/Bridgeport-Series-II-Interact-2-CNC-Mill/07-Schematic/schematic.jpg

 

[87cr250r]

That's a lot more $ and work than a switch

A transformer from the most expensive place to buy transformers from is $214.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

Motors with 9 leads or more can be rewired to run on 208-240 or 440-480 volt ranges. Can you rewire your motors? You can use a much smaller transformer to boost the voltage for your control circuit of you don't want to make changes there.

 

[Rik]

is this your Bridgeport II ?

If so, then Transformers T1 and T2 just need to re jumped for either 208 or 230 and so does the spindle motor.

It’s fully explained in the manual starting on page 3-4
Some fuses have to be exchanged to higher current ratings for the lower voltage

Thanks, I’ll look into this

 

[Rik]

Here's a Bridgeport II schematic. As @peapvp points out, it looks set up to convert;
http://igor.chudov.com/projects/Bridgeport-Series-II-Interact-2-CNC-Mill/07-Schematic/schematic.jpgView attachment 949162

I’ve rewired the quill motor but it doesn’t run unless I jump the contact’s in the back of the machine and it will only run in one direction but when the machine is put into low range or high range, the rotation will need to be changed and problem #1, problem #2 is the fact that it’s not safe jumping it. I’ll look for the T1 and T2 and see how I can move the wires to enable the machine to run on 220v

Thanks

 

[peapvp]

The Spindle Motor, or Quill Motor as you called it, has to be rewired directly on the Motor Terminals it self:



I usually replace the Overloads with 230V versions, the 460V overloads will trip after a few seconds when operated on 230V
eBay is a good source for those at very low prices

the two transformers T1 and T2 have to have only one wire moved. @2Pbfeet posted the wiring diagram

once the two Transformers are connected to 210V ( for 208V 3P ) or 220V ( for 230V 3P ) by just moving the wire #107 from TFU 2 on T2 and wire #112 from 5FC TB#4 on T1, then everything else will fall into place

T1


T2

 

[peapvp]

@Rik let me know if you need any help re configuring your Bridgeport.
A few years ago, a friend gave another friend of mine a Bridgeport clone made in Yugoslavia back in the mid 70’s.
This machine has a Siemens motor to drive the spindle. The Siemens motor is a 230 / 460 3 Phase 3KW motor which was retrofitted in the 90’s and had a burnt coil because they let it single phase.
We had the motor rewound for about 300 bucks locally.

I then converted the entire machine to run on 240/120 Single Phase with the help of the “3 phase capacitor converter box” available at the time via eBay,
I used one for the Siemens spindle motor with 5KW rating and the other for the 3 phase table motor with 1KW rating
The cooling pump is 120V

the only issue with those capacitor boxes is the loss off power. Spindle Motor is now derated to 1.5 KW which is fully sufficient in the low rpm range since this is a belt driven system

The table motor is now rated at 0.5 KW which is equally fine at low table advance speed, since my friend is mostly machining 1/4” and 3/8” thick Stainless Steel

 

[Rik]

The Spindle Motor, or Quill Motor as you called it, has to be rewired directly on the Motor Terminals it self:

View attachment 949170

I usually replace the Overloads with 230V versions, the 460V overloads will trip after a few seconds when operated on 230V
eBay is a good source for those at very low prices

the two transformers T1 and T2 have to have only one wire moved. @2Pbfeet posted the wiring diagram

once the two Transformers are connected to 210V ( for 208V 3P ) or 220V ( for 230V 3P ) by just moving the wire #107 from TFU 2 on T2 and wire #112 from 5FC TB#4 on T1, then everything else will fall into place

T1
View attachment 949171

T2
View attachment 949172

I swapped the 6,5,4 and 1,7- 2,8 - 3,9 together in the past to try to get the motor to run on the 220V and when I jumped the relays in the back of the machine the motor would work but......