MES Integration Series · Part 3
Real-Time vs Batch Data Upload
Should the machine send data continuously, on events or in batches?
There is more than one way to send machine data to the MES. Live tags show what the machine is doing now. Event messages record that something happened. Batch uploads send summaries at an interval. On-demand uploads move big files when someone asks. The right choice depends on how soon the MES needs the data and how much the network and the MES can carry. This page lets you compare them on your numbers. The values are examples.
| Method | Messages per hour | Data per day (MB) | Average delay | Worst delay |
|---|
The model makes parts at the rate you set. Continuous sends the streamed tags at a fixed sample interval. Event-triggered sends one message per part. Batch sends one summary at each interval. On demand is a person asking once an hour. The chart shows what the MES knows at each moment for the method you pick; the gap to the parts line is the delay.
| Data | Best method | Why |
|---|
Pick a data item and your own choice; the page compares it with the usual advice. There are good reasons to differ: a rule here is a starting point.
Every message is sent, and the MES acknowledges it. If the acknowledgement is lost, the sender cannot tell and sends the message again, so the MES can see it twice. With a unique ID the MES can recognise the repeat and store it once. Try the sliders: without retries data is lost, with retries and no unique ID the counts are wrong, with both the count is right.
The ID must be the same when a message is retried, and different for every different event. Combine the fields that identify one event; a timestamp alone is not enough if two machines can send in the same second.
The same part seen by each method. The delay before the MES knows is what you trade for lower load.
| Stage | Tools shown in the case | What they do here |
|---|
The tools are examples, not recommendations. Choose by what your team owns and what your machines and PLCs support.
The simulations are simplified teaching models. Choose update rates with the MES supplier and your IT team, and test the retry and duplicate logic with real failures.