MPG on port 3 problem

[M250cnc]

I have some movement using the MPG

But only forward and it is erratic

The pins on port 3 SS are marked 1 to 6

1 to 3 are inputs

4 to 6 are encoders

So that makes 9 pins numbered 1 to 6 

Any other help appreciated in setting the ports and pins correctly on port 3

Thanks
Phil

[Hood]

you dont need to put it on port3, I have mine on port2. Having said that it should work fine on port 3, I have the buffered outputs from my spindle servo drive on port3. There are two sets of inputs, cant remember which are which but some are differential and the others single ended. That means if you wish to use them for single ended MPG or for that matter just general inputs you will have only six available. The three differential have six terminals a+ a- b+ b- i+ i- if you are just hooking up a single ended encoder/mpg then the - ones dont get used.

Hood

[M250cnc]

Hi Hood,

Put it on a standard BOB it works fine

Which for me is a result 

Phil

[M250cnc]

Here is what doesn't make sense to me

9 pins excluding 5V & Gnd only 6 numbers to go round

Hope you see the pics

[Hood]

1A, 1B and 1I are inputs 1,2 and 3 on Port3
 2A+, 2B+ and 2I+ are inputs 4,5 and 6
2A- 2B- and 2C- are only used if you are connecting a differential encoder or Differential MPG to Port 3. A differential encoder will have A+ A- B+ B- I+ I-, a single ended encoder will only have A B and I

So if your MPG is single ended you just connect to  1A and 1B and then in ports and Pins, MPG page set it up as Port3 Pin1 for A and Port3 Pin2 for B.

Hood

[M250cnc]

Sorry Hood you have mad a mistake there.

There is the type that i have which has A, B, 0V & +Vcc 

So for dummies like me

A goes to 1A
B goes to 1B

And it would allow a total of 3 of these

1I & 2A = No 2

2B & 2I = No 3

Phil

[Hood]

yes, if you wanted 3MPGs then you could do that, you could also connect them to any pin on port2 or any of the inputs on Port1
But why would you want 3 MPGs? You related to Brett or something and have extra hands
Hod

[M250cnc]

No extra hands but i will have two MPGs so i can use my lathe manually (Sad i know)

I just love to turn the handles

And a index timing pulse for the spindle

It seems to me to be better to put the pulses directly in the SS without going through a BOB

Plus it means i don't need a second BOB which is a Scottish trait coming out. 

Phil

[Hood]

Well I know you cant have any Scots blood in you or you would be ashamed to have that avatar

Hood

[M250cnc]

The only Scots I've had in me is Scotch. 

Just tried the Mpg works a treat.

Now i just need to get me brains sorted. 

Phil