Issues turning on AE Pinnacle with TwinCAT 3 RS232

[DIN509E]

We have a Pinnacle power supply from Advanced Energy which we'd like to control using TwinCAT 3, via an EL6002 and RS-232.

I got the communication to work and can set every parameter I care for, but have issues with turning the output on.

I send the command to turn DC on [[FONT=&quot]08 | 02 | 0A], receive a positive answer [[/FONT][FONT=&quot]09 | 02 | 00 | 0B[/FONT]] and indeed, the power does rise, but only for a few milliseconds before the Pinnacle turns the output off for no apparent reason.

I used an RS-232/USB adapter and sent the same command via Python's serial library and the power stays on. No other parameters, like limits and timeouts, have been changed in between those tests.

I created minimalistic code to make sure no other communication was interfering. The first FB is creating the content of the message and adds it to the buffer, the second is running in a separate, faster task dedicated to background communication.

Message to buffer FB:

[...]
VAR
  fb_sendData : Tc2_SerialCom.SendData;
  [...]
END_VAR
--------------
IF b_dcOnButton THEN
  b_dcOnButton := FALSE;
  an_message := M_createMessage(2);
  fb_sendData(
    TXbuffer:= TxBuffer,
    pSendData:= ADR(an_message),
    Length:= SIZEOF(an_message)
  );
  b_error := fb_sendData.Error <> COMERROR_NOERROR;
END_IF

[FONT=&quot] Background communication FB:
[/FONT]

FUNCTION_BLOCK FB_backgroundCom
  VAR_IN_OUT
  TxBuffer : Tc2_SerialCom.ComBuffer;
  RxBuffer : Tc2_SerialCom.ComBuffer;
[...]
END_VAR
----------
fb_pinnacle_srlLineCtr(
  Mode:= SERIALLINEMODE_EL6_22B,
  pComIn:= ADR(stIn_pinnacle),
  pComOut:= ADR(stOut_pinnacle),
  SizeComIn:= UINT_TO_INT(SIZEOF(stIn_pinnacle)),
  Error=> b_pinnacle_ctrlError,
  ErrorID=> e_pinnacle_ctrlErrorID,
  TxBuffer:= TxBuffer,
  RxBuffer:= RxBuffer
);

[FONT=&quot]
Does anyone have any idea why this behaviour could appear or what I could test?

We have other issues with the device. I don't think they're relevant to this particular issue, but who knows.
[/FONT][FONT=&quot]1. When we control it using Profibus and set it to pulse between roughly 70 and 350 kHz, we get a "E051 PROFIBUS Watch Dog Expired" error.[/FONT]
[FONT=&quot]2. Having disconnected all bus cables and using manual control, we receive a "E020 Interlock Open: User". when operating pulsed above ~70 kHz. It's not an issue of an open interlock though.[/FONT]
[FONT=&quot]In both cases we suspect EMI.

Since I don't have a lot of experience, I welcome even the most obvious suggestions.
[/FONT]

 

[AlfredoQuintero]

Hello an welcome to the forum. I am not familiar with this device but I am familiar with Profibus and what you describe is consistent with what you are thinking. Problems with EMI. You must verify the grounding.
In the case of USB/RS232C make sure the cable is as short as possible and the baud rate should be the slowest the device allows. Also for Profibus, if you are able to use a slow baud rate it may be worth trying. Needless to say, you must use standard Profibus cables, connectors and terminators.

 

[DIN509E]

The issue was with the line

Length:= SIZEOF(an_message)

it sends too many bytes. After changing the code to transmit as many bytes as are in the specific message, the power supply stays on.