Centroid CNC control sales, service, training and support
The RTK2 has LEDs to indicate the status of its power supplies and its communication fibers.
Power status is indicated by five green LEDs on the short end board (RTK2D).
Fiber communication status is indicated by three red LEDs at the top end of the middle board (RTK2B).
In normal operation, with power applied and with the CNC software on the PC up and running, all five green LEDs should be lit, and the red "SHIFT" LED should be dimly lit.
With both 24VAC and 120VAC applied, and with the on-board switching power
supplies functioning properly, all five green LEDs will be lit.
If the 24VAC supply is absent, then the first two green LEDs ("PLC +5" and
"PLC +24" will be out. Also, all three red fiber communication status LEDs
on the RTK2B board will be out, and the PC software (CNC7 or CNC10) will report
"401 PLC failure detected".
If the 120VAC supply is absent, then the last three green LEDs ("OPTO +5",
"+12 VDC" and "-12 VDC" will be out. Fiber communications will be normal,
but all PLC inputs will appear to be open.
With 24VAC logic power applied, and with the PC software (CNC7 or CNC10)
up and running, the red OUT16 and OE LEDs will be out, and the red SHIFT LED
will be lit dimly. It appears dim because it is blinking on and off very
With logic power applied, but with no communication from the PC software, the red OUT16 and OE LEDs will be brightly lit, and the red SHIFT LED will be out. This is the normal condition when the control is first powered on, and the PC has not yet booted up and started the CNC7 or CNC10 software.
If this condition appears after the CNC7 or CNC10 software is up and
running, then there is a problem with at least the CKS (#2)
fiber, and you will probably have a "401 PLC failure detected"
message on the screen.
With logic power applied, and with a good signal on the CKS (#2) fiber coming from the PLC, but no signal from the TXS (#1) fiber, the red OUT16 LED will be brightly lit, and the red SHIFT LED will be dimly lit.
This condition should also cause a "401 PLC failure detected"
message on the screen.
If you have a "401 PLC failure detected" message on the screen, but all the status LEDs are normal, then the problem is likely with the RXS (#3) fiber, which carries communication from the PLC unit back to the PC.
CNC Services Northwest Home
Copyright © 2020 Marc Leonard
Last updated 21-Jan-2020 MBL