Strictly speaking this isn’t about the Onboard Ignition, but browsing other topics (like this particularly relevant one from 2017) makes me think I’m not too off-base asking here.
Summary: I’d like to access a number of numeric table entries from Ignition, but I can’t seem to figure out how.
I’ve been asked by a customer to set up some Ignition tags pointing to “all the alarms” in a SNAP-PAC-S2 that runs one of their systems. The alarms currently reside in a WonderWare/InTouch application that uses several topics configured in FSGateway to read the data.
When I arrived on the scene, the customer already had the CIrrus Link Opto 22 groov EPIC and SNAP PAC (v4) driver installed. They had had some trouble setting it up (detailed below in case it’s helpful, and because I have additional questions), but that seems to be behind us.
Now I’ve got the driver talking, and it’s finally time to get these alarm tags into Ignition, but they don’t show up when browsing tags. A closer look at the tags in WW reveals they are using array indices. Further investigating the control strategy (I’m not a regular user of SNAP-PACs by any means) tells me that these items belong to numeric tables. So I try a few variations on array indexing that do not work, and then I go looking and find the topic linked above. Unfortunately, the workaround link it points to has died in the meantime, and the Cirrus Link documentation no longer mentions tables at the top. As far as I can tell, this is from before the days when variables/tables had to be declared Public to be visible. I’m basing this on the fact that I can’t find anywhere I would do so. The controller firmware is R9.5h, from 2018.
So that’s my real question: How can I accomplish my goal of pulling this alarm data into Ignition? Ideally, I would prefer to do so without playing around in the controller itself (see: not a regular user).
We had a few issues with the driver that I didn’t understand. We’re working around both, but I’m hoping someone here can provide some clarity:
- Initially we were using an Allen-Bradley 1783-NATR (network address translation unit) to try to connect the SNAP-PAC-S2 to their plant network while also isolating it. I set up the public/private ports and the gateway on the SNAP-PAC such that pings were successfully travelling through the NAT device, and further added a rule to allow traffic through on port 22001, but I was never able to get the driver to show connected. In the end, we set the secondary IP of the device to an address on their plant network and just plugged in there. (Incidentally, I was astonished to discover that it seems to be impossible to put in three three-digit numbers for the IP address, so we had to switch from 192.168.100.149 to 192.168.100.79.) Are there other ports we need to set up, or is this just a non-starter of an idea?
- Once we got the driver talking with default settings (which took several minutes to go from Not Connected to Connected), we found that the WonderWare application was having a very hard time maintaining its own connection. It has a clock in the corner of the screen that normally updates once every second and change (so it misses about 20% of seconds), but as soon as the driver showed Connected it changed to often updating every 15 seconds or so. Fortunately, we don’t need the data in Ignition to be zippy, so I cranked the timeout and scan rate to 30 seconds and 2 minutes, respectively. It would be preferable to have smaller numbers, though, and I don’t like that as a workaround.