Welcome Products Applications Support Contact Us Login Suggested testing for Pulse and Signal Pulse - AT Editor Schematic The above schematic can be easily converted into an AT Test program using the AT EDITOR software. The simple schematic is shown here AT Editor schematic Pulse - AT Fixturing The 786 series of pulse transformers can be easily connected using a Kelvin pin fixture. As the winding resistance is low, (<1 Ohm), the testing will benefit from the improved accuracy provided by 4 wire measurements. Simple kelvin pin fixture Pulse - AT Test Program The resistances of the two coils are first checked to be below the specified maximum of 0.6 Ohms on each winding. Next the inductance is checked to validate the core operation, The limits here specify a minimum inductance rather than a nominal and tolerance, so only a check for greater than 2 mH is performed (although the AT will record the actual measured value anyway) Get PDF of test program Get At Editor ATP file for program Get AT Series Editor software Turns ratio is checked next to check the 1:1 ratio to limits of +/- 1%. If the actual number of turns is known, then it is best practice to use these as the nominal, with +/- 0.5 turns as the tolerance. Inter-winding capacitance and leakage inductance are checked next, again in line with the published data. As both these are largely governed by the design, some users may prefer to run these tests as occasional audit tests to save test time, whilst maintaining quality auditing. Finally the Isolation is checked using a standard AC HI-POT test. # Test Description Pins and Conditions Reason 1 R DC resistance Pins 1-3, Check < 600 mOhms To check the winding resistance is below a maximum. Also acts as a check of correct wire gauge and good termination. 2 R DC resistance Pins 6-4, Check < 600 mOhms To check the winding resistance is below a maximum. Also acts as a check of correct wire gauge and good termination. 3 LS Series Inductance Pins 4-6, 1 kHz, 100mV, Limits check L >2 mH To check the correct number of turns and correct operation of the core material 4 TR Turns Ratio Energise primary pins 1&3 at 1 kHz, 100mV, secondary 4&6, check for 1:1 ratio, +/- 1%, Positive polarity. To check correct turns and phasing on Primary to Secondary 5 C Inter-winding Capacitance 5V, 100 kHz, Pins 1&3 Hi, Pins 4&6 Lo, limits 49 pF+/-10% The capacitance is usually a function of the design of the winding positioning and topology, so is usually set by the design. However, you may occasionally wish to audit this during manufacture. 6 LL Leakage Inductance 50 mA, 300 kHz Pins 1-3 with 6-4 shorted, limits ; better than 470 nH Checks that coupling between winding does not result in excessive loss of magnetic flux transfer 7 HPAC AC Hi-Pot 1 kV 50 Hz AC, 1 second, Pins 1&6 High, Pins 2,3,4 & 5 Lo. Check current <1 mA To check isolation from primary to secondaries. AT5600 Run time 1.77 sec (AT3600 Run time 3.68 sec) NOTE: Many pulse transformers also define a “Volt time product” to define the energy capacity of the transformer. This is effectively already checked in the above test scheme, as the factors affecting this are a) the core, the core area and the saturation flux density of the core material (checked by the inductance test) b) the number of turns (checked by the TR test) AT Test Results for Pulse Transformers Pulse and Signal Links / References Murata homepage Murata 78601/1C datasheet A general article on Pulse Transformers Fixturing for pinned transformers Our App Note on 4 wire Kevin connections Our tech note on testing ferrite transformers Email Voltech USA 1-239-437-0494 EUR 44 1235 861173 ASIA 44-1235-364-012 Products Applications Support Service Contact Us Terms Of Business Terms Of Use Privacy Any problems or questions using this website? Let us know! Voltech © 2021 This site uses cookies on your computer to help improve your experience. Please read our Privacy Statement in the footer for further information. Otherwise, click AGREE and you're OK to continue. Cookie Information Agree