Thursday, May 29, 2014

Semi Conductor Tester - SemTest Part 4

Testing was done in part 3, this last part is consist of following:
Final assembly
The front panel assembly can now be lowered down onto the case. Make sure that the three ribbon cables are folded neatly into the space above the lower PCB and not caught between the edges of the case or lid. Fasten the case together with four M4 screws into the corner holes, then fit the knobs to the rotary switch and the pot and the assembly is complete. 

Testing the HV crowbar
It’s now necessary to check that the HV crowbar circuit is working correctly. To do this, power up the unit, wait a few seconds and then press the Menu Select button. You will get a display like this:
Device to Test:▲
1:Diode/Zener▼
Press Enter and then the Up button. The display will then show:
Test parameter:▲
Irev(OPV)▼
Press Enter again. Set the Device Operating Voltage to 25V, using the right-hand knob. Then press the Test On/Off button to start the test.