pattyo

Thanks for taking the time to help me out!

So, considering the ETN21 was produced long before the EIP21, is the EIP21 better, or just different? They actually cost the same exact amount - I was quoted $1100 each. Side note - I am using a Keyence vision system that supports Ethernet/IP but I hadn't planned on using that feature yet. I'm not sure I can justify setting up this type of network considering our facility is pretty small and each machine has its own dedicated computer already. It's also a mixed network with all the computers and stuff so there is a lot going on. Does anyone have any resources for learning more about Ethernet/IP? I'm trying to do this right, but don't have much experience with it and no one here knows anything about it. Thanks for the help so far :)

Thanks for the reply PMCR. Based on my research, the CIF41 ended up being no more than a ethernet-serial convertor, and the data rate is actually slower than USB 1.1. It works alright when the network is isolated as you mentioned, but cannot handle an actual network with a lot of other devices. Could you explain in layman's terms just what the differences between the ETN21 and EIP21 are? I don't have experience using the FINS protocol either.

Hi guys, I'm ready to purchase an ethernet unit and need help narrowing down my selection. I believe what I want is either the EIP21 or ETN21. Unfortunately, my knowledge of PC-PLC networking is not that great. Currently on a couple machines we have a PLC primarily operating the equipment, and a PC connected via USB that sends and receives word/bit data through the active X control through a visual basic user interface. This way, if the computer restarts or crashes, the machine can keep working (without HMI) until we get the PC worked out. It's kind of slow, but it works when there is not too much data transfer going on. We tried before to hook up a CIF41 ethernet plug-in and connect it to our network, but the communication was spotty and unreliable we assume due to too much network traffic. The plan is to upgrade to a "real" ethernet unit that can actually filter out network traffic, and hook the machine directly to the network. Unfortunately, we cannot have a dedicated equipment network at this time, so everything (PCs, printers, etc) are on the same physical network. It would also be nice to have things like a server capability in case we decided to create an intranet based HMI, but this is not necessarily required. I think it would be cool though. Basically, the primary goal is to be able to plug our PLC into the network and have a reliable, fast PC-PLC interface with a PC on the network running our visual basic software. No more USB cable. I'm leaning towards the ETN21, simply because I don't understand the added features of the EIP21. Any tips? Thank you!

So perhaps would a CJ1W-EIP21 (Shielded twisted-pair cable (STP), category 5 or 5e or higher. Tag data links and message communications supported) a better option if we wanted to integrate directly to our LAN? I can find out more information about our network configuration if that would help. Thanks for the input thus far.

Sorry, I said that part completely wrong. What I meant to say was the PLC and PC would lose connection. The data being updated on the user interface would freeze frequently and sometimes not update at all. We are using the CIF41 ethernet option board. This very well could be a network configuration issue. Unfortunately, our IT guy can't figure it out and I don't know enough about it to fix it.

Hey guys, First I want to thank you for the support in the past. We have our machine up and running and have hooked it into our company network in order to collect SPC. We have the PLC running so it can be standalone, but also have a PC running XP attached for a Visual Basic user interface. We basically store SPC in an access database on the network. The first problem we had was when we connected the PLC and the computer to the network, the PLC software would keep crashing. When doing nothing, the activity light on the ethernet module was blinking. We think the PLC was receiving too much network traffic and being overloaded, even though I thought ethernet protocol shouldn't really let this happen. In order to fix this, we isolated the PLC from the network by installing another network card in the PC and put it on a different subnet. Now we have the issue that the PC is extremely slow when accessing the network. The VB software is laggy and even doing simple windows explorer tasks are very very slow. How the heck do big companies set up their PC/PLC/Network with many machines? We are clearly doing something wrong. Any guidance is appreciated.

Ok, thanks guys. I went into the memory and found that the Auto Tune was not working, P=80, I=0, and D=0 so I decreased P to 50 to reduce overshoot, and increased I to 20 to eliminate steady state error. Bam fixed.

We have our set point to 35 degrees Celsius but the controller only controls to ~32C. We have to set it up to about 38C to get a 35C actual temperature. The hardware is clearly capable of maintaining the temperature, but there seems to be some kind of offset in the temperature controller. Connected to a CP1H-40XA CPU. It was working perfectly fine before.... Any help?

and here is cx server using 99% of the cpu

Here is the screenshot of the error:

We are using Visual Basic to retrieve data from CX Programmer using the active x control in CX Server, and will get a stack overflow after extended periods of monitoring. My coworker suspects that we are not retrieving data the way you should, and that the CXDBMS.exe process is crashing us. I know this is a very open ended topic. Is there a guide to the proper way to handle these types of communications with the PC?

Thanks Michael, that worked perfectly!

Does anyone know if there is a memory location that counts actual pulses sent from a pulse output when using the speed instruction? We are trying to compare sent motor pulses to actual encoder pulses, and it's hard to compare an absolute counter to an instantaneous frequency. (Our frequency is constantly variable based on other inputs) Thank you!

On our CP1H-XA we have some analog position sensors feeding into the built-in analog, and outputting 0-5V to two stepper motor drivers. We used shielded twisted pair 24AWG wire and were getting a lot of fluctuations in the motor speed. Motor speed is measured with some 10,000ppr encoders. We fixed the output values (to eliminate the sensor input variable) and still got a lot of fluctuation, like 5-20% depending on my mood and the alignment of the planets. I switched the drivers over to our analog output extension module and now they run perfectly smooth with <.01% fluctuation. Are the built-in analogs inherently noisy, unshielded, or could something be wrong with our unit?