Classic Chart secondary Y axis

I see it mentioned briefly in the Ignition manual, but no instructions on how to do it. I would like to add a secondary Y axis to a Classic Chart. I have three pressure values and three volume values. They’re related, but on drastically different scales. The pressures are between 0 and 100 PSI, while the volumes are between 0 and 21 SCFM. I’ve easily done this in Excel, so I know what I want to see.

I’m bringing the data into the chart via a SQL query. So how do I associate three data points with one axis, and the other three with a second axis?

under chart customizer>Datasets, add a new dataset. you would then build a query that contains all of the points that you want on your 2nd axis in that dataset. after you do that go to the tab for y-axis and add a new y axis. after that go to the tab for dataset properties and click on the new dataset that you created. from there under dataset properties change the y axis dropdown to your new y-axis.

1 Like

I’d love to see a screen capture video on how to do that. I swear I must be doing something wrong because I just can’t figure it out, and instructions on it are scant.

I dont have time for a video but Ill export the window. it is a 7.5.11 project

Thanks for that example. I opened it up and I see how to do… at least part of what I was looking to do. I still can’t figure out how to make the chart look exactly how I want. I’ve attached a screenshot of a chart I’ve created in Excel. I want to recreate it in Ignition.

Notice the primary Y axis (on the left) has a scale of 0 - 80. The secondary Y axis (on the right) has a scale of 0 - 16. Based on what I saw in your example, I can’t figure out how to make the scale of the secondary axis display on the right side of the chart like in my picture.

Did you try this?

Right-Click on the chart and go to the Chart Customizer.
Click the Y-Axis tag and change its “Axis Position” to BOTTOM / RIGHT.

Yup. Tried that. There appeared to be no change whatsoever in the chart. I’m going to delete this one and start over.

EDIT: I just tried it on the graph diat150 sent me and it worked, so something must be messed up with my chart.

UPDATE: I just realized I have to go to the Dataset Properties tab and tell the chart the second dataset which Y axis to use. GRRR! It’s working now. At least this part.

I still don’t like how the charts display gaps in time if a batch starts up today, and is re-processed in two weeks. Why would I want to see two weeks of nothing in the chart??? Doesn’t make sense to me. I’d rather just see the data for the batch together in the chart, without any gaps in time. But that’s a discussion for another thread I guess.