7/28/2013 6:25 PM | |
Posts: 18 Rating: (1) |
Hi All I have a problem with getting the analogue output redundany to work. I am using 414-5H PLCs and ET200M and the redundant analogue I/O cards. I have configured the cards to be redundant pair, i.e. PQW0 and PQW32. I am writing a value to QW0 (27000 about 20mA). I measured the output, display indicates correctly. Then I wanted to test whether this redundancy is working or not. I unplugged the connection from card with the add. PQW32. I still have the reading about 20mA. Then I placed the connection with logic add. PQW32 back and unplugged the connection from card with PQW0. My reading is gone. I read 0mA. So redundancy on analogue output doesn't really work. My analogue inputs redundancy setting worked perfectly. Below are my configuration and attached is the diagnostic file. OB 35 (process image PIP1)àFB450 RED_IN àMy FCs and My FBs àFB451 RED_OUT OB 72 (RED_FLT) àFC450 RED_INIT àFC451 RED_DEPA àFB452 RED_DIAG OB 82(I/O_FLT1)àFC451 RED_DEPA àFB452 RED_DIAG OB 83(I/O_FLT2)àFC451 RED_DEPA àFB452 RED_DIAG OB 86(RACK_FLT) àFC451 RED_DEPA OB 87(COMM_FLT) àFC451 RED_DEPA OB 100àFC450 RED_INIT OB 102àFC450 RED_INIT OB 122 (MOD_ERR)àFC451 RED_DEPA AttachmentDiagnose Redundancy.pdf (440 Downloads) |
7/29/2013 10:19 AM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308) |
Helloshenhao610, You should load OB70 (RED_I/O_FLT1). You should load OB85 and call FB452 (RED_DIAG) and call FC451 RED_DEPA at outgoing events of OB85.
Please use FB453 (RED_STATUS) to evaluate the 2 analog modules status before unplugging any of them to make sure they are redundant. When you unplug the 1st analog output module, read the module status word of FB453 and see if the unplugged module is already passivated. When you plug the module again, read the status word and make sure the modules are redundant again before proceeding with any further steps. Best regards. H-H
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7/29/2013 3:22 PM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308) |
Hellohshen-sync,
No, you don't have to call any FC/FB in OB70.
I can see that you are using channel redundancy software blocks. I don't have practical experience with channel redundancy but I'll try to help you as far as I can. It seems you start your test with an abnormal state. i think you have some channels that are already passivated before you start your test. I expect that your 2 modules are connected to some diodes and they are connected together to some terminal blocks. I hope all channels are connected. Do you have some free channels?! I recommend to put some test resistance of 1500 ohm across all terminal blocks of the 2 modules in question. This is to make sure that no undesired passivation takes place. When you finish connecting your resistances, You should go online in HW configuration window and make sure your redundant modules are working without any errors. Now, you should make a warm restart or you can call FC451 (depassivation function) to make sure all redundant pairs are working redundantly. You should start your test when you have ACTIV_L=1 ACTIV_H=1 CH_L =1 CH_H=1 If one of them is zero then one of them is passivated. This means redundancy is not even working to be tested. If it still gets you zeroes then we still have to diagnose why the modules/channels are not depassivated at start.
I've attached it for you. You can find it when you hit F1 on FB453, you will see a green link at the end called Depassivating channel groups that contains info. on module status word. Best regards. H-H
AttachmentPrinting _Depassivating Modules and Channels_.pdf (468 Downloads) |
This contribution was helpful to1 thankful Users |
7/30/2013 10:29 AM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308) |
Hellohshen-sync,
I'm glad you did it but I couldn't know where the problem was. I hope you would share your experience.
You can't use the VAT to write a value because the FB451 will always write the half value of required mA. Even if you don't use the QW, it is still configured as 4-20mA in HW. This means QW0 and its redundant QW (whatever) should be giving together 4mA all the time. The 2765 represents 2mA (half of 4mA) This means that RED_OUT is working correctly. If you are sure you don't use QW0 anywhere else in your program, you can use a simple move instruction but it must be calledbefore FB451. Best regards. H-H
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7/30/2013 12:11 PM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308) |
Hellohshen-sync, Thanks for sharing info.
No, It's just called once per process image partition. If your PIP is assigned to OB35 it must be called at the end of OB35.
If I may ask, Why did you split your code? You should move all your code to the OB to which the PIP is assigned. If your PIP is assigned to OB35 then you should move your code to OB35. If you need some separate sampling time of OB3X then we can start finding a solution but if you don't need such thing, then move all your blocks to a single OB3X. Best regards. H-H
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8/14/2013 2:21 PM | |
Joined: 2/29/2008 Last visit: 9/19/2024 Posts: 8 Rating: (0) |
Dearhshen-sync, I have a same configuration and have a problem in reading the Analog Input and Output. Can I have a sample program as u haved solved the problem. Thanking you, Pravin
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