Q-series coms / E-view

[Guest Guest_MIKE]

Can anyone help me? I would like to know what the best way to communicate a Q (00j or 01) with a master system that is allen bradley PLC-5. Help! gotta sort out soon in China. Also I have a problem with 'E-view'. The A2N PLC connected to PC running E-view 1.02 via ethernet. Rarely and randomly held on bits in the PLC prog when momentary mouse click. M0-100 are mapped as e-view bits and are used only on the ehternet. when mouse click a bit it can stay on continuously until PLC is reset. I have checked everything i can think of. Mitsi say my ethernet ladder logic is ok. E-view settings are all ok (momentary setting). It's weird cause the bit thats latching itself on is used once in the whole program (like a pushbutton). I'm planning on taking out all the 'momentary' mouse click bits in e-view and the ladder and just having 'set' function in e-view and reset in program. This is more fail-safe for com links, but it makes the program larger!

[navillusi 2]

I have heard of someone connecting a mitsubishi Q to an AB using the QC24 serial comms card and writing the DF1 comms code themselves, so it is possible, just depends on how much time you have!! The simple solution is to use an inexpensive HMI such as an E200 as a "babel box", connect both PLC's to it and use the "message exchange" function. This does work well, I have done it myself, though if you are also using the HMI to the usual HMI things, the data exchange can slow it down somewhat.

[JimRowell 1]

I'd like to know more about this problem you're having. Is it always the same bit(s) that sticks? What device number? Do you sometimes have to click more than once in E-View to get it to set? Do you have several that work properly (never stick) even though you are using them from E-View? There has to be 2 commands sent from E-View to produce a momentary action since there is no true momentary action available in the plc. First a set command is sent then after a short pause, a reset command is sent. There is reasonable (albeit not great) error checking done by the plc and a good/bad reply is returned to the sender (E-View) after each command. If noise is a problem I'd be surprised if only the reset command is being botched. I suppose it's possible that E-View does not properly check for the reply. You are there clicking until the bit gets set but then it's up to E-View to reset it on its own. If it's not checking the reply, then it's not resending the command until it gets through and that could explain it. However, I'd be surprised if E-View's programmers were that lax. As a workaround, you only need to add a single RST command into your existing code in the plc for each affected value. eg. change your code from: LD M0 [perform action] to: LD M0 RST M0 [perform action] Nonetheless, I'd really like to find out what's causing this problem you're having. If you post some or all of your code, we could perhaps offer some more help. If this is a problem with the plc or E-view, I'd like to understand it. If it's a problem with your code, I'm sure you'd like to understand it. Either way, you're a winner. While you're at it, why not register on MrPLc?