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● NC-200A1 PLC Program


There is problem between display screen (Monitor) signal to PLC unit (DVP-28SV), normally PLC (DVP28SV) send the all signals through RS-232 cable to monitor (Display screen unit) , If Monitor can not receive signal during 0.5 sec (few second) , the Monitor (Display screen unit) will send out the alarm message “ TIME OUT –COM-232”.


We need to focus the signal between DVP28SV and Monitor , There are following possible reasons:

  1. The RS-232 cable connector loose ---- Please check the RS-232 cable was connected well to motor (display screen) end and PLC unit DVP28SV end or not ? Besides there is another RS-232 middle connector in the side cable box at right side , Please open the Wire box and check the middle RS-232 connector was connected well and confirm the RS-232 cable is perfect , no problem,You can use electrical meter to confirm the RS-232 cable signal is OK. no problem.
  2. The other reason , Maybe it cause the PLC unit DVP 28SV fault , But in our experience , Few chance the DVP28SV happen problem , If you confirm the DVP 28SV was faulty , We can send you need DVP 28SV with PLC program for you to  replacement the PLC unit then you just send back the damaged DVP-28SV to us for checking purpose.
  3. The monitor side problem , We think it’s few chance happen the problem because the RS-232 signal wire is very low voltage


Regarding the wire (9) which is servo on signal for Y axis servo motor , Please connect to Y10 of DVP28SV position,
As for the PLC program , Hereby we send you the PLC program and install software and instruct manual  of PLC unit (DVP28SV) .
Please click the link below for PLC program information:


The most possible reason come from RS-232 cable , check RS-232 cable firstly then  check PLC unit DVP-28SV ,