• Home
  • Download PDF
  • Order CD-ROM
  • Order in Print
The Amperite Regulator-Cont.
PLUG IN THE POWER SUPPLY AND LOOK FOR

Neets Module 06-Introduction to Electronic Emission, Tubes, and Power Supplies
Page Navigation
  138    139    140    141    142  143  144    145    146    147    148  
3-48 Up to this point we have discussed only the individual sections of the electron tube power supply. In the next section, we will discuss the techniques of troubleshooting these individual sections and the total power supply. Q41.   What is the purpose of the amperite regulator? Q42.   As the tube filaments in the load heat up, will the circuit current increase or decrease? TROUBLESHOOTING POWER SUPPLIES Whenever you work with electricity, you must follow all the appropriate safety precautions. In the front of all electronic technical manuals, you will always find a section on safety precautions. You should also find posted on each piece of equipment a sign listing the specific precautions for that equipment. One hazardous area that is sometimes overlooked, especially on board ship, is grounding of equipment. By grounding the return side of the power transformer to the metal chassis, manufacturers can wire the cathodes of the tubes in both the power supply and the load being supplied by the power supply directly to the metal chassis. This eliminates the necessity of wiring each tube directly to the return side of the transformer, saving wire, and reducing the cost of building the equipment. While this solves one of the problems of the manufacturer, it creates a problem for you, the technician. Unless the chassis is physically grounded to the ship's ground (the hull), the chassis can be charged (or can float) several hundred volts above ship's ground. If you come in contact with the metal chassis at the same time you are in contact with the ship's hull, the current from the chassis can use your body as a low resistance path back to the ship's ac generators. At best this can be an unpleasant experience; at worst it can be fatal. For this reason Navy electronic equipment is always grounded to the ship's hull, and approved rubber mats are required in all spaces where electronic equipment is present. Therefore, before you start to work on any electronic or electrical equipment ALWAYS ENSURE THAT THE EQUIPMENT AND ANY TEST EQUIPMENT YOU ARE USING IS PROPERLY GROUNDED AND THAT THE RUBBER MAT YOU ARE STANDING ON IS IN GOOD CONDITION. As long as you follow these simple rules, you should be able to avoid the possibility of becoming an electrical conductor. TESTING There are two widely used checks in testing electronic equipment. The first is the VISUAL CHECK. Do not underestimate the importance of this check. Many technicians find defects right away simply by looking for them. A visual check does not take long; in fact you should be able to see the problem in about 2 minutes if it is the kind of problem that can be seen. You should learn the following procedure. You will find yourself using it quite often, as it is good not only for power supplies but also for any other type of electronic equipment you may be troubleshooting. 1.    BEFORE YOU PLUG IN THE EQUIPMENT, LOOK FOR: a.    LOOSE TUBES—A tube that is not properly seated in its socket may not be making proper contact with the rest of the circuit. It may very well be the source of your problem. Push the tube completely into place. b.    SHORTS—Examine any terminal or connection that is close to the chassis or to any other terminal for the possibility of a short. A short in any part of the power supply can cause considerable damage. Look for and remove any stray drops of solder, bits of wire, nuts, or screws. It sometimes helps to shake the chassis and listen for any tell-tale rattles. Remember to correct any problem that may cause a short circuit. If it is not causing trouble now, it may cause problems in the future.






Western Governors University

Privacy Statement
Press Release
Contact

© Copyright Integrated Publishing, Inc.. All Rights Reserved. Design by Strategico.