Haas indexer M-FIN signal

[Elam Works]

Hello all,

I have a 2006 TM-1 that I am installing a Haas indexer on. I have the Haas indexer control box, and initial thoughts were to hook up the 4-pin DIN cable (also Haas) to the spare M21 relay so the control can send the signal to the remote box and trigger the indexer to increment one line in its program. Down the road I hope to go full 4-axis, but that is a question for another thread. For now I am working with what I have on hand.

So in the indexer manual connecting to the spare m-code relay is straight forward. (Also it is explained well in the TM-1 manual.) In the indexer manual it also mentions the indexer control box can send a signal back to the mill that the index is done, and I would like to use that. This would save having to insert a dwell in the program, proportioned to the length of the index, before the tool moved back in to resume the cut.

So I located the unused socket on the TM-1 main board for "M FIN". Rather than the expected two terminals, I have four. Two have 12v (presumably the signal voltage) and two nothing. The question, is the M-FIN duplicated and able to receive a return signal from two independent devices? I suppose I could write a simple program to test this and complete the circuit between each pair of terminals, but I am always leery about back feeding voltages into circuit boards. Even if it is only 12v.

Another curiosity is the manual for the indexer it states the signal voltage is 24v. Readily available (low) voltages on my TM-1 are 5v and 12v. However I assume that if M-FIN provides 12v, it expects 12v back. So I suspect the manual is really stating is 24v is the maximum signal voltage that the indexer control box relay will handle.

So, has anyone else already tapped into their M-FIN?

Regards,
Doug

Ref: 2006 TM-1, 2002 TRT indexer

[Al_The_Man]

I have not implemented I/O on a Haas, But I would think the two optional FIN signals are or-ed in the controller, if there are two of them.
But normally the logic that implements an M code is written to either expect a FIN signal or to output without waiting for FIN, my question is, are you sure the M21 waits for a FIN signal?
For what is required on the FIN input, you need to know the nature of the input card? Is it sink or source contact closure?
I am just going by experience in Mitsubishi and Fanuc, I assume Haas uses the same principle.
But there I could be wrong!!
Al.

[Elam Works]

Al,

The M-FIN signal is optional, so no the M21 does not wait for it. Or so I am lead to believe, since the TM-1 manual makes no mention of the M-FIN in conjunction with M21 (except in the context of assigning it to an optional – not installed – extended range of M-code relays.)

Which does pose a new question, is there a Haas parameter to turn on/off a forced wait for return signal (activate M-FIN)? I will have to look in the parameter list for that. If it is default on, that is fine as I do want to use the M-FIN signal rather than estimating an appropriate dwell in the program.

The Haas spare M-function relays can be wired either normally open or normally closed. The indexer requires a normally open relay, and closing of the relay contact (for 0.1 second) triggers the indexer.

Sorry, I do not know what you mean by "or-ed".

-Doug

[Elam Works]

Actually a quick MDI program shows a M-FIN signal is required after a M21 is called. However I also found the parameter that turns the 'wait for M-FIN' on and off.

-Doug

[Al_The_Man]

However I also found the parameter that turns the 'wait for M-FIN' on and off.

-Doug

How does that affect M codes that do not require the FIN, is it selective or across the board?
Al.

[Elam Works]

Al,

Presumably it only effects the user assigned M-code relays where the machine control would otherwise not know if the signal was acted upon. Obviously any internal control M-codes (coolant/spindle on/off) the machine controler would know (withing its sensory abilities) if the command executed. I say obviously, as it has been running normally with the M-FIN parameter activated since 2006.

-Doug

[KenFoulks]

Do you still require assistance, or is this matter solved?

[Elam Works]

The use of M21 and resetting of the relay via the M-FIN signal is clear enough. However I still do not know why the M-FIN terminal has four conductors, two 12v and two null, except my original postulation that it is to allow for two independent M-FIN signals.

I have been waiting on a bulkhead connector to arrive so as to make a neat job of the M-FIN cable to the index control box. That should arrive in a day or so. If no responses by then, I was going to try the experiment I previously mentioned. Which is take the 12v M-FIN signal current and short it to the two null terminals and see if that clears the relay(s) as I suspect.

-Doug

[Elam Works]

I was sent a copy of the VF series manual, and in there it explained the 12v signal from MFIN is shorted to ground. This is not explainined in the TM-1 manual. While I figured the signal went out to the remote relay to complete the connection, it did not occur to me that it would be shorted out to ground. But indeed that is how it works.

What still remained unsolved where the four terminals (P100 on a 2006 TM-1) A little experimentation showed that bridging the center two terminals had the desired effect of cancelling the M21 relay. What the other two terminals are for remains a mystery, but I have a working MFIN signal now communicating with my indexer.

Thanks to all who offered help and suggestions.

-Doug