Hurco Hawk 5M Retrofit w/ existing motors

Typically LinuxCNC does not deal with the tachometer outputs, as these are normally
connected to the motor drives for velocity feedback.

The Z encoder signal is the encoders index channel and connects to the 7I77 index input

If the motors have mechanical brakes you will first need to find how these are driven.
Brakes are often take considerable current so its not likely they can be driver directly by
7I77 outputs.

The hal side of brake control is often somewhat involved because you must typically
release the brakes about 100 ms before you enable the drives to avoid getting a drive fault.

In that case, then I won't worry about the brakes, at least not at this point. Just want to get operational first. For what its worth when I first opened the electrical cabinet on this machine the tach wire going from the x motor to the x drive was cut and zip tied to the other wires next to it. It was obvious that some had deliberately done this. I may be completely wrong but this led me to believe the tach feedback wasn't 100% required. So my connections would be as follows:

- Servo Pins -
Signal - Pin - Connection
Va1 - A - 7i77 qa0
Va1 - B - 7i77 qa0
Va2 - C - 7i77 qb0
Va2 - D - 7i77 qb0
Va0 - E - 7i77 idx0
Va0 - F - 7i77 idx0
Motor Earth - G - Ground/Earth
+5V - H - 5vdc power supply positive
0V - I - 5vdc power supply negative
B+ - J - brake unconnected
B- - K - brake unconnected
Shield - L - connected to cable shielding
T2- - M - tach unconnected
A2- - N - servo drive negative
T1+ - O - tach unconnected
A1+ - P - servo drive positive

- Servo Drive -
aout0 from the 7i77 and the gnd pin will connect to the drives diff sig in pins to provide the +-10vdc

If I hook all of this up I should be able to start the PID tuning process correct?

The original drive --> motor cabling should connect the tachometer to the drives
If the drives were setup for velocity mode (which is very likely) they _require_
tachometer feedback or they will not be controllable.

Also note that you should absolutely expect runaways (and running into hard stop and breaking things or hurting peole)
and so, its much safer to do initial tests with the motors disconnected from the linear axis.

The first thing you should get working on the servo drives is the enable logic
(so LinuxCNC can enable/disable the drives) This is a safety issue.

Regarding brakes, typically the motor will be locked unless the brake is powered
so if you do actually have brakes on the motors, the shafts will be locked with power off
(often brakes are only used on the Z axis to avoid coasting into the table when power is off)

Tha makes sense about the way the brakes are applied. I can confirm that with the power disconnected I can rotate each of the motors by hand, including the Z. The machine has belt reduction on all three motors too. I fully expected the runaways, I've got the motors off the machine and strapped down on the bench for testing. the drives are bolted onto a frame that included the DC power supply. It has the 3 drives with a connector on each for the diff signal, tach signal, and limit switch inputs. There is also power connection to each of the servos, Pins N and P. There is a single 24vdc controlled relay on the frame of the unit that interrupts the 115vac coming into the power supply. It appears as though this want meant to enable/disable the drives. After looking through the documentation I was sent from servo dynamics it does show that each of the drives has a pin to enable/disable it externally, however, it's not being used. I'm not sure If I should deviate from the "stock" wiring and connect these pins to an estop circuit or just rely on the relay that already there being controlled by the estop circuit.

Edit: the machine has a pneumatically actuated mechanical brake on the Z.

Well, I got a set of schematics from a very helpful gentleman at Hurco that has allowed me to finish the wiring on the servos and their controllers. Everything on the hardware side is ready for a bench test, I've got everything wired to Encoder 0 on TB3 and Driver 0 on TB5. I just can't make heads nor tails of the pncconf names for the pins. I'm stuck on this step: linuxcnc.org/docs/html/config/pncconf.html#_mesa_i_o_setup

When you start pncconf and get to the "Mesa Card 0" page, select:
"5i25-Internal Data"
and
"7i77x2 With One 7i77"
and then
"Accept Component Changes"

And the pin names should make more sense

Thank you very much for the fast reply. That's what I had done. on i/o connector 3 tab, I have Muxed Enc 0 set to X Encoder but I have no idea what X HALL and X Grey are. It keeps telling me to configure pwm or stepper signals.
Edit: Nevermind It wasn't showing all the pins because I told it I only had one encoder and one drive, it shows up now. I'm on the open loop test now trying to get it to move the servo.

Your picture showed that you have the wrong card and firmware selected (5I20 and SVST4_8)
did you skip the "Accept Component Changes" step?

that link just points to the linuxcnc documentation page that I was working through to get this up and going. I have the 5i25 and 7i77 with the 7i77x2 firmware installed and verified. I can use the cli to toggle the LEDs on the card so I know I am communicating with it. I went back and made sure I clicked Accept Componet Changes which gives me a connector 2, connector 3, 7i77i/o, and 7i77 pwm tab. I selected the encoder and output. Still not getting any movement though, I'm completely lost at this point. I was trying to follow the documentation to avoid asking so many questions but I'm stuck.

Before even connecting the 7I77 I would verify that you can move the motors with a 1.5V battery
(with the drives enabled) If this doesn't work you need to find out why before proceeding