High Speed Testing
The new all solid state programmable current source allows fast test algorithms. Test times are super fast, increasing productivity and lowering labor costs. Typical test times are:
1. Ramp up, verify ratio, iterate to test level, measure, compare to limits, display results: 4 seconds 2. Polarity check and reversal: + 1 second. 3. Degauss function: + 1 second.
One advantage of high speed testing is low heating. Due to the ramped modulation and low duty cycle of the current waveform, the R.M.S.. heating of the CT under test and test system components is approx. 1/5 that of conventional test systems. Low heating allows smaller and lighter test system components, making Model CT- 4000 smaller, lighter, more reliable and less expensive than competitive equipment.
Auto-Ranging
The Auto-Range software option is especially useful if the CT to be tested is mislabeled or the ratio is not known. Auto-Ranging software does not require the operator to program a ratio. The test system will automatically find the correct ratio for the CT under test and display RCF and Phase data Auto ranging software requires the Universal Reference.
Non-Standard Ratios
In normal use, Model CT-4000 will allow the user to program only the ratios defined in the test system specifications. Other ratios will not be accepted and will generate error messages. If the Model CT-4000 test system is equipped with the Universal Reference** option, then any ratio may be programmed and tested within the allowable range of ratios and currents. Universal Reference ratios must be integers. There is no loss of accuracy when testing universal ratios. |
Multiple Test Points
A test point is defined as a specific combination of ratio, test level and burden. It is sometimes desirable to measure CT RCF and Phase at various test points while the CT is connected to the test fixture.
Two test modes are available:
1. Single point testing. If the single point test executive algorithm is selected (by clicking on a desktop icon), the displayed form will prompt the operator to select the test conditions from the stored test program data base, or enter the test conditions manually. Test conditions are always checked for illegal data before testing can start. When the operator presses the START button, measured values of RCF and Phase are compared to test limits and displayed. The RCF and Phase data may be printed in a certificate and/or may be saved on disk (archived) for future reference. Test Data saved to disk is in CSV format suitable for Excel or Access.
2. Multiple point testing. If is desired to test a CT at multiple points, such as at different test levels or burdens, then the multiple point test executive should be used. The multiple test algorithm prompts the operator to enter the name of a user defined test sequence table. Each sequence table contains a list of test programs. Each test program in the list defines a different test point. The multiple point test executive tests the CT test according the test programs in the list, generating an array of RCF and Phase data for each test program. The multiple point RCF and Phase data may be printed in a test report and/ or may be saved on disk (archived) for future reference.
Saving the test data to disk takes only milliseconds. Printing a certificate or report may take a few seconds, but the multitasking capability allows simultaneous testing and printing.
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**Patent Pending |