110 module will not boot reliabily

[shorton]

I use 110 modules and have one that has developed a problem. If it is powered up, it works properly on the initial power on. Heartbeat LED blinks.

If I turn it off, and then turn it back on, the module will not "boot". There is power to the board (24v) but the heartbeart LED is not blinking.

I found that if I leave the module off for a few minutes, it will power back up properly.

I tested the voltage on the power pins and it reflects 24v on power up, and upon power off the input voltage measured at the board connector slowly ramps down from about 2.4v and begins to level off at about 0.5v.

Also, I have found that if I 1)power the modlue on, and 2) leave it on for just a few seconds, then 3) turn it back off, and 4) wait for the input voltage line to sink to about 0.8v, then 5) power it on, it will boot properly.

On the other hand, if I power the module on, then leave it on for 15 or more seconds, I must wait for over a minute before I can power it back up and have it boot properly.

The device is turned on and off "softly" via a solid state relay as was suggested by Trinamis some tiem back. The input line voltage (at teh board connector) tested disconnected does not exhibit the slow ramp down described above. It cust from 24.3v down to 0v in a second or so. The ramp donw is coming from the board itself.

I looked at a "good" module and it *appears* the good module ramps down a little more quickly, but I dont' really ahve anything to measure the voltage ramp-down speed.

To be thorough, I did a factory reset on the module and reloaded my code to be sure software was not the casue. My code is stable and in use in hundreds of other identical modules. So far, only this board is exhibiting this issue. The issue is obvious as my code is set to auto-start and since this board will not boot reliabily, it never gets to the autostart code.

On a "good" module, I can power it off, then back on immediately. It will boot properly even if I switch it off then back on with a second.

Can someone with Trinamic identify or suggest what the problem is with this board?

Thanks in advance as always.

[Olav Kahlbaum (TRINAMIC)]

This sounds as something got wrong with the hardware. I can only make some guessses: maybe the 5V linear regulator (the 7805 on the back side of the board), one of the bigger capacitors. It could also be the CPU itself. Please measure the 5V in a case where the module does not work.

[shorton]

This sounds as something got wrong with the hardware. I can only make some guessses: maybe the 5V linear regulator (the 7805 on the back side of the board), one of the bigger capacitors. It could also be the CPU itself. Please measure the 5V in a case where the module does not work.

Olav, thnk you as always for the reply. My apologies for not getting the next test done more quickly.

I did check the 5v on the board while the board was in it's failure condition. When I apply 24vDC as described above, the 5v appears on the 5v output pins instantly. When I turn the 24v back off, the 5v line goes back to 0 (0.1v) again, very quickly. The 5v regulator appears to be working properly.

So with that piece of information, can you suggest what the casue of the boot failure described above may be? Is there something I can test next to isolate the issue?

My concern is not so much this single board, but the many others in service.

Thanks.

[Olav Kahlbaum (TRINAMIC)]

It is always not very easy to make a remote diagnosis on such issues, but I guess that something is wrong with the CPU itself. Please exchange the board (it would be good for us if we could have it for analysis/repair so that we have a chance to see more exactly what went wrong there).

[shorton]

It is always not very easy to make a remote diagnosis on such issues, but I guess that something is wrong with the CPU itself. Please exchange the board (it would be good for us if we could have it for analysis/repair so that we have a chance to see more exactly what went wrong there).

I understand completely. I will contact my distributor today and see if I can arrange to ahve them return it. Otherwise I'll get you to get me a shipping address and I'll send it directly. Thanks, Scott