Microtest cable/harness tester adds the quick intermittence open circuit function
In addition to the following measurement items of Microtest cable/harness tester series 8740, 8751 and 8761: (1) Open/Short;(2) Conductance; (3) Components; (4) AC Hipot; (5) DC insulation/ Hipot; (6) Quick conductance (7) Intermittence O/S, and a new test item “(8) Quick Intermittence open circuit” is newly added.
The quick intermittence open circuit is an extended function of the existing intermittence short open circuit. Regardless of the short circuit or the open circuit, the intermittence short open circuit will analyze all of the loop states of the tested line. Therefore, the scanning time is in mS (milliseconds). The quick intermittence open circuit only analyzes the open-circuit state. Analysis of short-circuit state needs to locate the corresponding short-circuit connecting points. Therefore, it takes longer for the overall test. Since the open-circuit state only needs to analyze whether the connecting points are on-state or not, it reduces significantly the test time. The time for detecting the open-circuit is 40μS (microseconds), which represents a 40μS or more open-circuit activity that has guaranteed detection. The quick, intermittence open-circuit and the intermittence short open-circuit can be set separately, to be included or excluded in the test items, or both to be ticked included in the test items.
Currently on the market, there are many cable/harness products that welding is not used to fix the connecting points during the manufacturing process but the clamping piece or the contact spring is used instead. This way of manufacturing is easier to cause an intermittence open circuit. Since it is fixed with the clamping pressure, the resultant open-circuit phenomenon is merely momentary. The mostly seen is the Dupon wire, which will cause no short-circuit problems. The connection end also uses the clamping pressure method, which is the functional detection that needs the quickest intermittence open-circuit test.
The early intermittence short open-circuit testers only have the function of determining PASS/FAIL. The number of the single function testers is now getting less and less because of its few scanning point positions and few test result files. Therefore, most intermittence short open-circuit testers have been integrated with cable/harness testers.