Thyristor Semiconductor Products Page 58 Thyristor

2014 Littelfuse, Inc. Specifications are subject to change without notice. Revised: 12/14/14 Teccor brand Thyristors AN1006 3. Set observed dot to top left corner of CRT grid by turning the Horizontal position knob. When testing is complete in Quadrant IV, return dot to original position. 4. Repeat Procedure 16. Quadracs Quadracs are simply Triacs with an internally-mounted DIAC. As with Triacs, Quadracs are bidirectional AC switches which are gate controlled for either polarity of main terminal voltage. To connect the Quadrac : 1. Connect Trigger to Base Terminal (B). 2. Connect MT1 to Emitter Terminal (E). 3. Connect MT2 to Collector Terminal (C). To begin testing, perform the following procedures. Procedure 1: (+)V DRM , (+)I DRM , (-)V DRM , (-)I DRM Note: The (+) and (-) symbols are used to designate the polarity of MT2 with reference to MT1. To measure the (+)V DRM , (+)I DRM , (-)V DRM , and (-)I DRM parameter: 1. Set Variable Collector Supply Voltage Range to appropriate Max Peak Volts for device under test. (Value selected should be equal to or greater than the device's V DRM rating). 2. Set Horizontal knob to sufficient scale to allow viewing of trace at the required voltage level. (The 100 V/DIV scale should be used for testing devices having a V DRM rating of 600 V or greater; the 50 V/DIV scale for testing parts rated from 300 V to 500 V, and so on). 3. Set Mode to Leakage. 4. Set Polarity to (+). 5. Set Power Dissipation to 0.5 W. ( 0.4 W on 370) 6. Set Terminal Selector to Emitter Grounded-Open Base. 7. Set Vertical knob to ten times the maximum leakage current (I DRM ) specified for the device. Note: The CRT readout should show 1% of the maximum leakage current. The vertical scale is divided by 1,000 when the leakage mode is used. Procedure 2: (+)V DRM and (+)I DRM To measure the (+)V DRM and (+)I DRM parameter: 1. Set Left-Right Terminal Jack Selector to correspond with the location of the test fixture. 2. Increase Variable Collector Supply Voltage to the rated V DRM of the device and observe the dot on the CRT. (Read across horizontally from the dot to the vertical current scale.) This measured value is the leakage current. (Figure AN1006.18) WARNING: Do NOT exceed V DRM /V RRM rating of SCRs, Triacs, or Quadracs. These devices can be damaged. 50 nA 50 V E R T H O R I Z S T E P V DRM I DRM Figure AN1006.18 (+)I DRM = 51 nA at (+)V DRM = 400 V Procedure 3: (-)V DRM and (-)I DRM To measure the (-)V DRM and (-)I DRM parameter: 1. Set Polarity to (-). 2. Repeat Procedures 1 and 2. (Read measurements from upper right corner of screen). Procedure 4: V BO , I BO ,V BO (Quadrac Trigger DIAC or Discrete DIAC) To connect the Quadrac: 1. Connect MT1 to Emitter Terminal 2. Connect MT2 to Collector Terminal (C). 3. Connect Trigger Terminal to MT2 Terminal through a 10 resistor. To measure the V BO , I BO , and V BO parameter: 1. Set Variable Collector Supply Voltage Range to 75 Max Peak Volts. ( 80 V on 370) 2. Set Horizontal knob to 10 V/DIV. 3. Set Vertical knob to 50 A/DIV. 4. Set Polarity to AC. 5. Set Mode to Norm . 6. Set Power Dissipation to 0.5 W. ( 0.4 W on 370) 7. Set Terminal Selector to Emitter Grounded-Open Base. Thyristor and Rectifier Testing Using Curve Tracers (continued)

Previous Page
Next Page