Drive Shows 100% Torque—but 100% of What?
A torque percentage is incomplete without its reference base. Check whether the displayed value relates to rated motor torque, drive capacity, or another configured quantity.
Illustrative percentage conversion; use the exact drive parameter documentation.
What is happening?
Drive estimates, motor ratings, and mechanical output torque describe different things. A percentage can change meaning after motor-data or scaling changes even when the screen label remains the same.
Check these five things
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Read the exact parameter definition in the drive manual.
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Confirm the configured motor data.
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Identify whether the value is estimated or measured.
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Check any PLC conversion applied to the drive parameter.
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Separate motor-shaft torque from gearbox-output torque.
Worked example
If an illustrative display is explicitly based on a 10 N·m rated motor, 150% corresponds to 15 N·m at that defined reference. It does not automatically mean that level is permitted continuously or available at every speed.
Quick diagnostic reference
| Question | Why it matters |
|---|---|
| Percentage base | Converts to physical units |
| Duration limit | Separates peak and continuous use |
| Measurement point | Avoids gearbox confusion |
The mistake to avoid
Do not increase torque limits to make a percentage look acceptable. Mechanical and thermal limits remain independent constraints.
How to verify the fix
Verify the displayed percentage against the documented base and operating envelope. Preserve the definition in HMI help or maintenance notes.
Field-work boundary: These are educational diagnostic guides. Use the exact equipment manuals and approved site procedures. Electrical testing and machinery changes belong to qualified, authorized personnel; control hazardous energy and validate affected functions before release.
Technical reference
Oriental Motor: Technical reference and motion sizing. The examples and diagnostic tables above are original teaching material; they do not replace the product manual.