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Question 1:
Is there an output pin for an external Estop/reset safety circuit to read the status of 7i77 WDT? If not, would it be feasible to use one of the existing pin outputs by Keeping this output pin ON while the watchdog timer has NOT bit. Here where the catch 22 comes into play, when the WDT bites, the hostmot2 driver disables the digital outputs therefore my external hardwired circuit will not be able to determine the WDT output pin status (see diagram Highlighted in RED). One way I can think of to solve this puzzle is to restrict the WDT from internally disabling the digital outputs, and have WDT just set a flag and let the hardwired safety circuit take care of disabling the power to the digital outputs.       Or I am out to lunch?Question 2:
7i77 field terminal block has several terminals I am hoping to be able to keep the field power OFF to the digital outputs until the safety lockout circuit is reset and the field digital inputs and VIN powered while the ESTOP circuit is active. If you look at the wiring diagram, I need the numbers of the terminal blocks marked with question mark (highlited in green). Nomenclature:
CR# – CONTROL RELAY
MCR - MASTER CONTROL RELAY
F# - FUSE
DI – DIGITAL INPUT
DO – DIGITAL OUTPUT
PB – PUSH BUTTON
WDT – WATCH DOG TIMER
L1 - MAIN SUPPLY LINE 120 VAC
N - MAIN SUPPLY NEUTRAL
PL- Pilot Light A brief explanation to what this hardwired circuit does follows this diagram.
  The wiring circuit diagram below  is a hardwired circuit that will allow power to be removed from digital outputs, servos and spindle. The circuit achieves the following:

• If power is lost during operation the machine will not restart when power is re-established.
• If an Estop is activated or a fault occurs during operation, the circuit will inhibit (prevent) power to digital outputs, servos and spindle. The rest of the machine control circuit will stay in the ON state; this will enable you to troubleshoot and resume operation without major reinitialization of the machine.
• Machine will not restart until all faults are corrected and operator presses reset button.

This hardwired circuit is the equivalent of safety relay without guided contacts.

I've got a 5' x 10' CNC router with a failed Mach 3 control. It has Yaskawa Servos (SGMGH-09ACA61) and was set up for step/dir with an ethernet smooth stepper. It was "open loop" with that control. It has four motors for the 3 main axis and a 5th motor for a rotary axis. I might not use the 5th axis but I do have a crazy idea for an automated dust collection "axis" that would probably use stepper motors. 

I have a Mesa 7I76e that I bought several years ago for another machine that has yet to be completed and I think this would be my fastest/easiest control to drop in but would still leave me open loop to the control. Instead I've been thinking of running with analog servo signals and the encoder feedback into LinuxCNC using a 7I92TF with a 7I77 or a single 7I97T. It seems the 7I97T might be a bit light on general I/O since the machine has an ATC spindle and several other pneumatics that need to be controlled and sensed so I'm leaning towards the former combo. 

Any suggestions wrt to Mesa card availability and the advantage of using analog vs step/dir in this application? 

 

Why a 7i96 and a 7i77? Can't the VFD be set up to accept an analog speed command, and therefore controlled by one of the free axis on the 7i77? These are both FPGA cards, so you end up with a lot of reduntant processing, and also a lot of unused features on the 7i96.

Are all your outputs on the same voltage? I ended up short of 24V outputs, as I had to put one rail of the 7i84 on 5V.
Good choice on a 7i73 in the user interface panel is a huge time saving in wiring reducing the wiring from the User interface down to the electrical panel to a single Cat 5E, plus one discrete for the E Stop.
Are you not using encoders for Jog/spindle/feed overides? These are slow enough to use normal pins and software encoder.

Have you considered 7i97/7i84/7i73?

Another option is the way I did it on my lathe. I split up all the functions with:
7i92 for the FPGA, plugged straight into:
7i85 interfacing the axis and spindle encoders, and providing 5 channels of RS-485 SSfor:
7i84 I/O (I might need to add a second one)
7/83 Analog servos
7/73 User control panel.
That leaves two spare RS-485 SS ports, so it will be easy to connect in the second 7i84 (once I find space for it in the electrical cabinet), and maybe a second 7i84 for jog wheels down on the apron.
 

Hello,

I am in the process of ordering the necessary components to retrofit my CNC mill. I just worked my way through the mesa selection guide and worked with the configuration tool. Now I would like your help verifying my selection so that as a beginner I don't make a costly mistake that could have been avoided.
The requirements are as follows:
3 analog servo drives with feedback from glass scales
1 Spindle vfd
3 mpg handwheels
34 digital inputs
18 digital outputs

At some point I would like to add physical buttons to the operators console, which would be realised with an 7i73 in the console.

The PC is in the operators console as well, and can only be connected to the mesa cards via ethernet.

In another post tommylight suggested I use the 7i97t, which can support my servomotors and the mpgs as well as a few inputs. Ideally i would expand this with a 7i76, however that is not available for me in europe.

Following the guide I came up with a different setup. As FPGA card I could use 7i96s and then connect 7i77 with the 25 pin connector. That leaves the smart serial connection for later use with the 7i73.
7i96s: Main FPGA board, controls spindle, 3 MPGs(6 inputs), 5 inputs, 6 outputs
7i77: controls the servo motors, takes the feedback from linear scales, 32 inputs, 16 outputs
7i73: keys and encoders on the operator control

so that should have me covered, or am I missing something?
 

Hey guys

just a quick update here.

we worked out the original diagrams of the machine and connected up a lot of  the hydraulics to allow basic operation of the machine

first we connected up the hydraulic pump and checked it was rotating the correct direction.  for those that don't know if a three phase motor is going backwards just swap any 2 of the 3 wires and it will reverse

so we swapped the 2 wires on the main line in and then repowered up the machine

halcmd -fk is your friend here

just type it into the terminal  and then you get auto complete of all the loaded pins on the machine and signals etc.  It is a seriously awesome tool

just to be crystal clear.  "quote marks" mean that this is a Hal command

also i am guessing at the actual pin names just to be clear they are probably not correct..

so the command "setp" turns a pin on or off
 setp hm2-7i92.0.7i77.output.00 1  (this will turn the first output on the mesa 7i77 card which will turn a relay on which will then turn on my hydraulic part.

we did this for all the hydraulics and got to a stage where we could remove the tool in spindle
spindle is hydraulic which is nice and easy

next plan of attack was to get the pallet changer going

current status is all hydraulics are working.  just need to get the motor working to rotate the pallets and swap them and it should be working

I will code a few things in classic ladder just to make it automatic.  and then i need to go through and setup timouts just in case there are other issues and i am not watching.

and thats it for now

hopefully next week i get more time to work on it and get some videos going etc

cheers 

andrew