Door Interlock

[Talyrond]

Hi,

When I press feed hold and open the door the program aborts. I’d like to be able to close the door and continue. I can’t see any parameters related to this on the Oak. I can see Acorn has 985 that looks related, but that does not appear on the OAK

Any ideas?

Thanks

Julian

[cncsnw]

There is no pre-written feature that is just waiting for you to set a parameter, to configure the countless variants of door interlock logic.

Instead, you will need to modify the PLC program logic to do what you want.

Your PLC program is based on the factory "Centroid-Mill-Standard-OAK-r7.src" program, and includes the following default logic:

Code: Select all

;================================================================
   SafetySwitchInterruptStage
;================================================================

IF DoorClosed_I THEN (SafetySwitch_M)
IF !SafetySwitch_M && (SpinStart_M || KbSpinStart_M || M3_SV || M4_SV)
  THEN ErrorMsg_W = SAFETY_SWITCH_SPINDLE_MSG_C, SET ErrorFlag_M

IF !SV_JOB_IN_PROGRESS THEN SET SafetySwitchToolCheck_M
IF !SafetySwitch_M && !SafetySwitchToolCheck_M && SV_JOB_IN_PROGRESS
  && !(M3_SV || M4_SV)
  THEN ErrorMsg_W = SAFETY_SWITCH_OPEN_MSG_C, SET ErrorFlag_M, SET SafetySwitchToolCheck_M

IF SafetySwitch_M THEN RST SafetySwitchToolCheck_M

There appear to be two error conditions related to having the door open.

The first, which displays the message "8093 Close Door to Operate the Spindle", is triggered if the door is open and either the spindle is running in Auto spindle mode; or if the door is open and you start the spindle in Manual spindle mode. Interestingly, it does not appear to be triggered if you start the spindle in Manual spindle mode with the door closed, then open the door.

The second, which displays the message "8092 DOOR INTERLOCK OPEN", appears to be triggered if the door is open while an automatic program cycle is running (SV_JOB_IN_PROGRESS); and Auto mode spindle run has not been requested (no M3 or M4 request); and the "SafetySwitchToolCheck_M" flag is not set. That flag is a little puzzling, as it does not appear to have anything to do with Tool Check. Its effect seems to be to make the 8092 error appear if the door is opened while a cycle is running; but to prevent the 8092 error if you start the cycle with the door already open.

Regarding your request, to suppress one or both of these errors, if the control is in Feed Hold: you could simply add "&& !FeedHoldLED_O" to either or both of the error tests. However, that would then allow the spindle to continue running while the door is open.

Do you want your operator to be able to open the door and reach into the machine, during a program cycle, with motion in Feed Hold but with the spindle running? Or do you want to require that the spindle be stopped as well; else trigger an error that will stop the spindle and the cycle?

[Talyrond]

Hi Mark,

Thanks for the info. Firstly you are correct in that if I start the spindle manually then I can open the door and it still runs. Also the program will start with the door open and the axis move but it will stop when a spindle is commanded, I’d rather the axis did not move, while in auto, at all with the door open.

I don’t get any message if I try and start the spindle manually with the door open. It won’t start, which is good, but should I see ‘8093 Close Door to Operate the Spindle’ in the message panel?

Nor do I get 8092 DOOR INTERLOCK OPEN when trying to start in auto with the door open, again it does not start, so that’s good. The only message I get is when I open the door when running, and that is ‘Operation abort: job cancelled’.

My wish is to be able to open the door, reach inside, and then close the door and continue. When the door is open, I’d like no axis movement and the spindle must turn/stay off. I’m happy to have to press feed hold and manually turn off the spindle to open the door, but if it could just feed hold and stop the spindle on door open that would be even better. I guess I would have to manually start the spindle or could that be done as well?
My door switch is just that, no solenoid to keep closed.

I may get you to do all this for me to be honest, anyway let me know what you think

Many thanks

Julian

[cncsnw]

While it is nice to have everything happen automatically, it does make the PLC logic quite convoluted.

In contrast, an implementation where the operator must first pause motion and spindle; then opens the door and works inside; then manually restart spindle and motion, is quite straightforward.

[Talyrond]

OK, understood. I'll contact you off line directly.

Thanks

Julian