Ready Steady Eddy

[EddyCurrent]

Good timing lads !

@silyavski, the temperature switch was already built into my spindle, it is closed normally and opens at high temperature.
@cncJim, see latest drawings

Here are my latest drawings



Features
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Strategy 1

* Emergency stop immediately signals VFD to stop and several seconds later (time to be assessed but possibly 6 seconds) delayed contacts of Guardmaster safety relay open to operate STO (Safe Torque Off) feature of VFD which disables control voltage and power semiconductors.
* Power removed from Stepper Drivers via Guardmaster safety relay and K1
* Stop command issued to Mach3 via K1 (even if Mach was still active the VFD and Stepper Drivers would still be disabled)

Strategy 2

* Stop signal sent to VFD via K3 relay
* Stop command issued to Mach3 via K3
* Enable (ENA) signal activated via Mach3 and BOB to disable stepper drivers

Strategy 3

Not implemented - same as Strategy 2

Strategy 4

* Stop signal sent to VFD via K4 relay
* FeedHold command issued to Mach3 via K4
* Enable (ENA) signal activated via Mach3 and BOB to disable stepper drivers

Strategy 5

Not implemented


Notes:

Strategy 3 could be implemented by incorporating a relay contact from K3 into K1 coil circuit however because all 4 contacts of K3 are being used another single contact relay would have to be connected in parallel with K3.
Strategy 5 could be implemented by removing the Pause push button and having only K4-4 contacts operational.

* A PAUSE push button has been added, this will stop the VFD and send a FeedHold signal to Mach3, to continue the ON (RESET) push button is pressed.
* A Charge Pump relay has been added to the Emergency Stop circuit this so the system can initiate an Emergency Stop if the software stops or communication is lost.
* If the Circuit Breaker for the Stepper Drivers trips then K1 will de-energise and send a STOP signal to Mach3.
* ENA signal now connected from BOB to all Stepper Drivers

( ** As yet I have not cobbled together the Charge Pump relay but I think a small 5v coil one will do the job as my BOB can source 20mA. **)

Relays K2,K3 and K4 are these
http://www.ebay.co.uk/itm/1set-Base-...item5d388b7d84