SAJID HUSSAIN ANSARI
Joined: 04 Jun 2008
Posts: 1
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 13 Jun 2009 22:26 PROBLEMS IN USING THINGET PLC |
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I have used 1st time the Chinese brand PLC i-e Thinget Model No. XC3-60R-C with the following expansion modues :
(i) RTD Module for PT100 (XC-E6PT-P),
(ii) Analog Input module (XC-E8AD) ,
(iii) Analog Output Module (XC-E2DA). and
(iv) Color HMI Screen TP560
I found the following problems :
(i) For the Relay output module I used the following logic for operating the relay Y5,Y6 & Y7 as follows :
M103 Y5
|-----| |---------------------------------------|-------( S )----------|
| Y6 |
|-------( S )----------|
| Y7 |
|--------( R )----------|
| |
M103 | Y5 |
|-----| / |-------------------------------------- |-------( R )-- -------|
| Y6 |
|-------( R )---- -----|
| Y7 |
|--------( S )-- ---- -- |
The logic is working properly and the set relays are monitored on PLC as operated relays (Their respective LEDs ON), but the contacts of relays are not shorted / closed. Hence the actual device / load is not working due to not operating of physical relays Y5, Y6 & Y7 (however the Online program and LEDs on PLC are showing correct status of energized relay). I Have also checked that the same output relays are not used at any other location of program. Please identify that whether it is software problem or hardware and what is its solution. We replaced one PLC unit with other PLC unit but the same type of fault has occurred on both PLC units. Some contacts of relays are working and some contacts are not working. It is also to be mentioned that I also used internal relay contacts i-e M5,M6 &M7 instead of relays Y5,Y6 & Y7 for set / Reset and the from that relays I operated Y5,Y6 & Y7 but the condition remains the same.
(ii) The second problem was faced in HMI Screen where the HMI software was used to develop buttons for activation of different tasks. We observed that the buttons formed in centre position of HMI Screen are not activating using touch screen, however the buttons formed in upper & lower portion of screen are operating well. This is also observed that when the same buttons are shifted to upper & lower portions of screen then they starts working.
(iii) The 3rd Problem was faced in RTD module, where the temp value received from RTD module has an error of many degrees C. whether it is possible to calibrate the module so that the correct reading can be obtained from the RTD module.
SAJID HUSSAIN ANSARI
C&I ENGINEER
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