Stated Torque Accuracy

This summary is intended to provide a comprehensive understanding of torque accuracy and the differences between full-scale and of reading accuracy specifications. Advanced Torque Products uses the of full scale method to provide customers higher usable accuracy throughout the torque range.

Accuracy of Full-Scale

Definition:

Torque tolerance remains constant throughout the full scale of the tool.

 

% Error of Full-Scale =
|Torque Reading – Target Torque|
Full Scale Torque
x 100
Torque Tolerance =
± ( Full Scale Torque × Accuracy of Full Scale )
  

Accuracy of Reading

Definition:

Torque tolerance increases by a fixed percentage of target throughout the full scale of the tool.

 

% Error of Full-Scale =
|Torque Reading – Target Torque|
Target Torque
x 100
Torque Tolerance =
± ( Torque Target × Accuracy of Reading )
  
Learn about our High Accuracy series

What will this example cover?

Below we will provide examples and explanations of a typical comparison our customers present us with, which is between a ±1% of full-scale option vs a ±3% of reading. The below example is a working calculator that you can also adjust to evaluate your specific scenario to help you more easily compare and summarize the different solutions you are looking at.

Wrench Capacity

5,000 ft·lbs

Wrench capacity is represented by the numbers along the bottom axis of the graph.

Target Torque

4,000 ft·lbs

The target torque for the example application is teal. The label represents margin of error.

Of Full-Scale Accuracy

± 1%

Of Full-Scale is represented by the blue lines and light blue label boxes in the graph.

Of Reading Accuracy

± 3%

Of Reading is represented by the red lines and light red label boxes in the graph.

Step 1: Wrench Capacity

Select the wrench capacity to meet your application needs. The selections are based on available ATP models.

Step 2: Target Torque

Select the closest target torque for your application. These options will change based on the wrench capacity you selected.

Step 3: Accuracy (Full Scale) ATP

Select the % accuracy at full scale for the ATP model wrench you are evaluating for comparison.

Step 4: Accuracy (Of reading) Other

Select the % accuracy at of reading for the other model wrench you are evaluating for comparison.

Note: The Full Scale vs. Of Reading comparison calculator shown below is only available on a desktop.

Advanced Torque Products uses the of full-scale method.

Our clients require the best accuracy we can provide. Since tools are generally used in the mid to high range of their capacity, we can provide our customers with better stated accuracy by listing our accuracy percentage of full scale rather than of reading. For those requiring greater accuracy, we also have our HA Series offering ±0.4% of full scale up to 30% of the tools capacity and then ±1% for the 31% to 100% range of the tool.

See ATP Digital Torque Multipliers

U.S. Patent Nos. 8,434,389 & 8,991,284

European Patent No. 2396147

Canadian Patent No. 2,752,088

Japanese Patent No. 5699338

U.S. Patent Nos. 8,434,389 and 8,991,284

European Patent No. 2396147

Canadian Patent No. 2,752,088

Japanese Patent No. 5699338