My 7i76e Connection Sheet

thx for the quick reaction i can go work on mine project in thise way prepairing a 180puls enconder is ABZ enough or do i need also the inverve pulse-A-B-Z
an other problem why an unloaded steppermotor stall at higher speed ?
i make several test and always the same result the stepper motor will not run
i use a mesa 7i76e
i try a nema 17 motor with a lowcost stepper driver 6600 from alliexpressalso
i try it with a leadshine dm556 driver
from xinlichuan the mc425e and mc442e driver with all the same result
i use a small, the adjusted and a high a curent
what more can i try ?

fons wrote: thx for the quick reaction i can go work on mine project in thise way prepairing a 180puls enconder is ABZ enough or do i need also the inverve pulse-A-B-Z

The inverse pulses would be generated by a line-driver, not by the encoder itself.
Single-ended works fine.

why an unloaded steppermotor stall at higher speed ?

Steppers have a lot of poles, so the back-emf becomes a problem at lower speed than with a lower pole-count motor.

To run faster, use a higher voltage. What voltage are you using? what is the max that your drives can handle?

Hello Norbert,

I´m working to retrofit an EMCO VMC100 Mill, your connection sheet helped a lot for wiring.
Thank you for the great job you´ve done. MESA´s documentation to their 7i76e delivered more questions than answers to me ...

Robert

This sheet helps me a lot.
Just a question. I connected my 7i76e b board with a 5v isolated Power supply at P3 First just left it like that to test Stepper Motors etc. Then I added field power to Tb1 as on your sheet however I did not connect it to Tb3 since I assume that is powered by the 5 volt power supply. When starting linuxcnc I get an error. It warns me about undervoltage.

Also if I measure on pin 5 I get 24 volt.
But there is no power on pin 1-4

I see the manual says both power supplies should have common ground. In my case both are isolated power supplies. Does that mean I should connect the negative poles of the two power supplies together?

@newbynobi

Thanks again for the connection sheets.

However there seems to be a minor flaw in it concerning the Field Power connection as pointed here out by PCW: forum.linuxcnc.org/plasma-laser/40517-do...ons?start=120#193043

Nothing should connect to TB1 pin 5 (VIN)
VFIELD (TB1 pins 1..4) is where +24V power goes

From the manual:

The isolated field I/O on the 7I76E runs from a switching power supply that can be powered by field power or a separate supply (VIN) with ground common with field power.Normally the 7I76E will be powered with field power and an on card jumper, W1 allows VIN to be connected to field power. If you wish to use a single power supply for the 7I76Es field outputs and field logic power, W1 should be placed in the left hand position. This connects field power to VIN. If you wish to use a separate supply for VIN, W1 Should be placed in the right hand position.

Your schematics works but the bulk of the field power current goes through the Jumper W1 instead of just the power for the field I/O processor. Also manipulation of the jumper when powered might damage the output drivers.

Quick question regarding pull up resistors and opto couplers driving the input pins. As my servo driver uses opto couplers for outputs.

With VField @ 24v a 2k 0.5 Watt resistor would suffice per input ?

(24^2)/2000 = 0.288W

As the alarm output from the driver pulses a 1hz the HAL flip flop comp would be the best way to catch the alarm signal ?