Mesa 7i76e setup help!

Does my board needs to be powered with 24v? Right now I'm using P3 connector with a 5V power supply.
From what you said I understood that that for the limit switch one wire will be connected to one of the TB5-TB6 pins 1-16
I thought the other wire should go at GND, from what you're saying I understand that it should go to +5V.
PS: thanks for the encoder advice!

The isolated field I/O section needs to be powered by 12V to 24V (Orange connector)

Then limit swiches should be wired from field power (+12 or +24V) to the isolated field inputs (TB5 and TB6 pins 1 through 16)

Hi guys,

I've finished putting all the electronic in the box and I got the motors and spindle encoder running.
Now I will have to work with I/O pins. I have a 12v power supply, but I don't know exactly on which of the power connector to link it.


Why are there 1 to 4 VFIELD pins? Can I supply different voltages on each of them?
I suppose I should wire the GND to pin 8.

What are the other pins for?
I will need to link an mpg pendant, and the encoder requires 5v power supply.
How do I get the 5v from field power? Do I need to use a dc to dc transformer?

The VFIELD pins are duplicated to limit the maximum current per pin to < 1 A for long term reliability.
If your total field output load is 1A or less you can just use one VFIELD pin.
DO NOT connect different voltages to the VFIELD pins as the pins are connected together on the 7I76E

The MPG encoder can be powered by any convenient 5V source
if you do not require isolation from the 7I76Es logic 5V you can use that
Otherwise a switching regulator or even a LM7805 running from field power will do

Hi PCW

With your advices I've managed to wire the limit switches and the spindle encoder. So far I was testing turning the encoder by hand (not mounted on the machine), and the software updates the rpm in the user interface.
Today I've mounted the encoder on the spindle and noticed that the RPM is much lower than the spindle speed itself.
Before buying mesa board, I was using a board over the paralel port, and the rpm was correct.
I have configured in the Pncconf the spindle encoder scale, mine has 360ppr, so it calculated 1440.
The spindle runs at about 150RPM, and the software says its 37-38RPM.
Any idea why this is not correct?
Thanks for your help so far!

can you post you current hal/ini files here?

Edit:
Also 37/38 is pretty much exactly 150/4 which
suggests a wrong counter mode setup or
encoder spec issue

How much does the encoder rawcount pin change with a single turn of the spindle?

Here are my .hal and .ini files
I have disconnected the limit switches so that's why you don't see them here.
I've looked over them, I don't see anything suspect...
I just hope there is not a hardware issue with the mesa board

The encoder has 360ppr, that's what I've set in the tab where it asked me the ppr of the encoder. It multiplied that by 4.
Not sure I understand the last question:

How much does the encoder rawcount pin change with a single turn of the spindle?

I have changed in the ini file the value of encoder scale 1440 to 360 and now the speed reading is correct.
Is there a bug or it it something I'm missing out?

with a 360 points per revolution quadrature encoder you will have 360*4 counts per revolution. If you turn one time the spindle it should count 1440.