Topics

1

General Mach Discussion / What is this relay? See attached image and what is the "charge pump" cct for?

« on: December 13, 2011, 08:54:25 PM »

Hello Everyone,
Ive been diagnosing a problem with my machine. Last week a PC power supply went BANG!! and it took something else out along with itself when this happened. Since that time, I have not been able to get the various relays to engage in order for the machine to run.. this where my problem lay.

I have a campbell B/O board. I am not sure if it is functioning as it should. I have been able to trigger all the relays.. So I suspect that its intact. Im missing somethng and I just cant put my finger on it...

Firstly, what exactly is a charge pump and how it is usually incorporated into a safety cct? IE Estop cct?

Secondly, As I was investigating the various relays and their functions, I found one on top of the Z axis servo, situated between the motor case and the encoder.. It is a 24 vDC relay and I am not sure of its purpose.. does this sound like a typical placement for a relay? what would its purpose be?  Any insight would be very much appreciated.

Thanks in advance. 

JR.

2

General Mach Discussion / bench testing the parallel port and pins -questions and issues

« on: December 10, 2011, 03:42:06 PM »

HI all,
I'm pretty new to this side of the game. I have a basic knowledge of how mach runs off a parallel port,but before i do something potentially foolish, I'm wondering if someone could give a little direction.

First of all, I just d/l'd mach and licensed it. Its not yet connected to anything. I opened up the ports and pin page, set the e-stop to active low (green tick mark) saved it and returned to the main screen. Port address is good also just in case..
Correct me if I'm am wrong but I should be able to press e-stop and be in a ready state? Correct?
Ive watched Art's video and what he is doing does not match the results that I am experiencing...something is amiss.
If I return to ports and pins and change e-stop to active high (red x) and save settings, when I return to the main screen and press e-stop, I should NOT be able to clear the stop... Is this correct?

the reason I ask is because regardless of the pin setting, Mach will clear the e-stop if I depress the button. Am I missing something?

And lastly,

Ugh.. Is it okay to place a jumper directly into a  printer port? - to activate the e-stop cct? or a limit sw. and if so can whatever input pin that is selected be grounded to any to the pins between 18 and 25? ie.. to e-stop on a campbell b/o board pin 10 port1 to ground.
the reason I ask is because my multimeter is reading 5 v on all pins... -except 18-25... Is this right? I feel that I am missing something and when I realize what that is. I'll feel kinda silly, but enlightened.

I hope this sort of make sense.. I'm really really fresh and green when it comes to this side of things..

Thanks in advance..

JR.