STARTER always has two copies: the offline project on your PC and the online parameter set in the drive. They drift whenever the drive is changed without updating the project. The online/offline comparison (while connected) lists every difference. It tells you what differs; deciding which side is right — upload or download — is your engineering call.
- A project is a snapshot, not a live mirror.
- Compare first, export the list, then decide.
- Learn the benign differences: name, IP, hours.
- When unsure, upload.
Two Copies of the Truth
| Offline project | Online drive | |
|---|---|---|
| Lives on | Your PC (project folder) | Control unit memory |
| Updated by | Upload (Load to PG) | Download, keypad, BOP-2, PLC writes |
| Available | Always | Only while connected |
| Represents | A past moment | What the machine does now |
What Makes Them Drift Apart
| Cause | How it shows up |
|---|---|
| Keypad / BOP-2 edit during a breakdown | Ramps, limits or minimum speed differ, with no record |
| Another engineer’s project copy | Many differences everywhere |
| Motor ID repeated | Stator resistance/inductance differ slightly |
| Drive replaced, project not updated | Device name, IP, serial-linked values |
| PLC wrote parameters acyclically | Values changed with no human involved |
| Macro changed on site | p0015 plus a large BICO block |
Learn to audit a drive properly
Hands-on STARTER comparison, backup discipline and change control on live SINAMICS hardware.
Running a Comparison (Try It)
Open the matching project → Connect → select the drive → start the online/offline comparison → review the list before touching anything. Practise below: create a change, compare, export, then sync.
| Parameter | Offline (project) | Online (drive) | Group |
|---|
Simplified trainer, not Siemens software. Parameter numbers are typical G120 examples.
Reading the Results
| Group | Examples | Action |
|---|---|---|
| Expected | Device name, IP, operating hours, serial-linked | Ignore |
| Meaningful | Ramps, current limit, min speed, macro, control mode | Investigate |
| Alarming | Motor nameplate, telegram, safety configuration | Stop and resolve |
Deciding Which Side Wins
Hands-On Lab: Find a Change Nobody Documented
Hands-on- '+LABPRE+'
Prove the copies match
Open the backup, connect and compare before anything changes.
Let a colleague change three things
A ramp, a minimum speed and a current limit, saved with p0971 = 1, without telling you.
Find them
Reconnect and run the comparison.
Export before acting
Save the list and note, per parameter, which side should win and why.
Sync the safe way
Upload the drive into the project and compare again.
Spot the macro signature
Change p0015 on the drive, save, and compare.
'+CHECK+'
Frequently asked questions
What is the difference between the online and offline project in STARTER?
The offline project is the file on your PC, accurate as of the last upload or download. The online data is what is in the drive now. Nothing keeps them synchronised, and because the drive can be changed from the keypad or by a PLC, the project is usually the stale copy.
How do I find out what someone changed on a drive?
Connect to the target system with the matching project open and run the online/offline comparison. It lists every parameter where the two differ, with both values. Export the list before you act.
Which differences are normal and can be ignored?
Device name, IP address, operating hours and serial-linked values differ by design on a renamed or replaced unit. Ramps, limits, macro and control mode are meaningful. Motor nameplate data, telegram selection and safety configuration should stop you until you know which side is correct.
Should I upload or download after finding differences?
Upload when the drive runs well and the changes look like deliberate on-site tuning: you capture knowledge and change nothing. Download only when you can justify replacing the drive’s behaviour, after uploading the current state. When unsure, upload.
Why did a comparison suddenly show dozens of differences?
Usually because p0015 (macro) was changed. A macro rewrites a whole block of BICO interconnections at once, so one change produces a long list. Check p0015 first.
Why should I compare before making my own changes?
So the list shows only what was already there, not a mix of someone else’s changes and yours. It is the cheapest documentation habit in drive engineering.