CNC10 Version 2.36 on Boss 5 machine

[748rdave]

Bit confusing but its this contactor which clicks in during startup. Shown at the top of the first picture on page one of this post. Added a larger picture to hopefully help.

[cncsnw]

In the absence of wire markings and a corresponding schematic, there is no way to tell what a contactor does, except to follow all the wires that are connected to it.

Since it appears to be the only contactor outside of the spindle starter set, it is reasonable to assume that it is intended to be the emergency stop. However, it might also be a latching power-on contactor, if the person who built your control liked to do things that way.

If it is the emergency stop contactor, and yet it closes (and later opens again) even when you have the hand pendant and/or the lower drive relay output plug unplugged, then it is not wired per standard or recommended practice, and it is anyone's guess how it actually is wired.

At some point you may need to just hire a competent local technician to figure out how your control was wired, how it was supposed to work, and why it is no longer working.

[748rdave]

I'm learning a bit on electrics here and tomorrow I will trace the wires back to see exactly where they go. I have the original drawing for the system wiring.
Title : Ajax cnc control for a bpboss. Date: 040903. Filename BPBOSS1.S01. Drawn by: RRJ.

I've always thought it to be the contactor shown in C5 section of the drawing.


Thanks for all your help cncsnw

[cncsnw]

If the large wire on the 43-44 pole is the positive DC leg, coming from the rectifier and going to the VM+ terminal of the DC3IO, then yes, that is likely intended to be the emergency stop contactor.

The main challenge will be to follow the coil circuit: how does power get to its A1 and A2 terminals?

All that said: if your issue is really that the control starts up normally, and runs normally for a minute or two, and then the computer spontaneously shuts down, then you probably have a faulty computer power supply. It is likely an ordinary ATX supply, installed in the PC case.

[748rdave]

My PDF file will show the wiring from the contactor. I have also left a message with the guy who did the original install if he's still about.
PC runs after cut-off displaying a " no VGA signal "

[cncsnw]

There should be two more terminals on the contactor, typically labeled "A1" and "A2", for the coil power circuit. Somewhere near the A1 and A2 terminals, the contactor should have a label indicating what the coil operating voltage is.

The circuit through the 13-14 normally-open contacts apparently prevents the spindle contactors from closing if the E-stop contactor is open.

The circuit through the 43-44 normally-open contacts apparently prevents the servo drive from getting motor power if the E-stop contactor is open.

The device in your lower picture (green board with capacitor) is a 3-phase rectifier for making DC power for the servo drive to power the motors. I hope there is a step-down transformer somewhere, so that the 3-phase AC input is 110VAC or less leg-to-leg.

[cncsnw]

PC runs after cut-off displaying a " no VGA signal "

The PC and the monitor are separate things, running from separate power supplies.

What evidence is there that the PC is still running, when the monitor is displaying "no signal"?

[748rdave]

There are two more wires connected one goes to the grey terminal block to the right of the contactor and the other goes down to another terminal block shown in the first picture on page one of my post roughly in the middle right hand side. I will check to see what the coil operating voltage is.

The step down transformer is located at the bottom left of the cabinate also shown in my first picture.

The PC fan is still running and the start button flashes slowly.

[cncsnw]

Does the PC start button also flash slowly when it is working properly (showing a display on the screen and responding to keyboard input)?

[tblough]

Slowly flashing (breathing) start buttons usually mean the computer is sleeping.