What is the main cause of composite error?
Analysis of the results from laboratory studies show, that for such condition primary current up to which the current transformer will comply with the requirements for composite/ratio error is decreased. This is caused by increased magnetic flux density in the magnetic core, which may even lead to its saturation.
What is total composite error?
Total Composite Error – error in the part gear comprised of both run-out and tooth-to-tooth error, checked using a master gear.
What is composite method of gear inspection?
The composite test of a gear is a method of inspection in which the work gear is rolled in tight double flank contact with a master gear. AGMA defines this type of inspection as “radial composite deviation.” No backlash is provided, as the work gear is spring-loaded against the reference gear on the inspection machine.
How do you calculate CT ratio error?
To calculate the percentage ratio error,divide the exciting current by the secondary current times 100.
What is composite error in CT?
Composite Error of a Current Transformer (CT) is defined as the rms value of difference between the ideal secondary current and the actual secondary current. Composite error is used to express the accuracy of protection class CT. You might have seen protection class CT 5P.
What is composite error in current transformer?
Accuracy of a current transformer is measured by the composite error. This is defined as the difference between the ideal secondary RMS current and that of the actual secondary current. The ratio of the accuracy limit current to the rated current is the ‘accuracy limit factor’.
Why is composite test performed on a gear?
Composites provide much improved mechanical properties such as better strength to weight ratio, more hardness, and hence less chances of failure. So this work is concerned with replacing metallic gear with composite material so as to improve performance of machine and to have longer working life.
Which instrument is used for composite gear inspection?
Dial indicator primarily measure irregularities in the gear under inspection. A dial indicator of high resolution is used to measure the composite error, errors due to runout, tooth-to-tooth spacing, and profile variations.
How is CT calculated?
The CT ratio is the inverse of the voltage ratio. In this example, the voltage ratio is 1:5, so the CT ratio is 5:1. This means the current level is stepped down 5 times where, if the primary current is 200 amps, the CT output is 40 amps.
What is TPS current transformer?
TPS – low leakage with performance defined by secondary excitation and turns ratio error. TPX – defined by peak instantaneous error during specified transient duty. TPY – as per TPX, but remanent flux limited to 10%
How to fix USB composite device error in Windows solved?
USB Composite Device error in Windows Solved 1 Press Windows key + R to bring up Run command 2 In Run command window, type control panel and click OK 3 In the search bar of Control Panel window, type troubleshooting 4 Click on Troubleshooting 5 Click Hardware and Devices 6 Follow the on-screen instructions to run the troubleshooter
What is the composite error of a current transformer?
Definition: Composite Error of a Current Transformer (CT) is defined as the rms value of difference between the ideal secondary current and the actual secondary current. It includes ratio error, phase error and the effect of harmonics present in the exciting current. Composite error is used to express the accuracy of protection class CT.
When to use composite error for protection class CT?
Composite error is used to express the accuracy of protection class CT. You might have seen protection class CT 5P. Here 5P means a Protection class CT whose composite error shall not exceed 5% at its accuracy limit primary current. To be more clearer, consider 5P10 CT.
When does composite error of CT not exceed 5%?
To be more clearer, consider 5P10 CT. This means that the composite error of CT will not exceed 5% when primary current is 10 times of the rated current. Before we go into the calculation part, first of all we understand the term ideal secondary current. Ideal secondary current means the CT secondary current when following are assume: