TTB-9-2920-225-34-1 Regulator Check Out and Repair 100 Amp 2920-00-900-7993 Download
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TB 9-2920-225-34-1 CHAPTER 2 VAP-AIR MODELS Section I. INTRODUCTION 2-1. Introduction. Four models were produced by Vap-Air, a division of Vapor Corporation. Code Ident 80234 (FSCM) Vapor Corp. 6420 W. Howard St. Chicago, IL 60648 In 1978, the voltage regulator product line was sold to DC Electronics Corporation. Code Ident 34904 (FSCM) DC Electronics Inc. 544 N. Highland Ave. Aurora, IL 60506 TELEPHONE AC 312844-5170 DC Electronics now provides parts and engineer- ing support for all Vap-Air models. The Vap-Air part numbers for each model are: 26440001-01 26440001–03 26440001-04 26440001-05 2-2. General Inspection. This chapter applies to all Vap-Air models. a. Regulator Box Assembly (external). Check for missing or stripped cover, connector mount, retainer screws, and voltage adjustment access plug. Check connectors for signs of arcing, bent, or pushed in pins, broken connectors, and thread damage. Correct deficiencies by utilization of serv- iceable components from unrepairables or requisi- tioning components from the manufacturer. (1) The pin receptacle (J2) is P/N 7064706 FSCM 19207 or MS3102A28-22P FSCM 96906 per MIL-C-5015. (2) The socket receptacle (Jl) is P/N 7064- 706 FSCM 19207, an Army number for which there is no equivalent NSN number. An assembly is available from Bendix. CODE IDENT 77820 (FSCM) Bendix Corp. The Electrical Components Div. Sherman Ave. Sidney, NY 13838 It should be ordered as part number 60–42228- 10S; it will arrive as a complete assembly with the shell marked 8701337. b. Regulator Box Assemblly (internal). If water leakage or corrosion is detected, it is possible that extensive damage has been done and the regulator cannot be easily repaired. Components should be performance tested and retained if acceptable. Check for disconnected or burnt wires, missing components, and replace repair as necessary. Carefully remove the transistor mounting plate, noting the position of the screws, washers and rubber insulators. Visually inspect the circuit board for burnt components. Replace the circuit board through cannibalization if burnt compo- nents are found. Carefully reinstall the transistor mounting plate. c. Regulator Verification Check. After perform- ing the above inspection, if the regulator appears to be in good condition, check its performance on a test stand. If the regulator fails this check, pro- ceed to the following component tests. 2-3. Bench Testing. Figures 2–1 and 2–2 show the method for testing NPN transistors; these figures apply to all models in this chapter. If the original transistors are replaced with substitute part num- bers, the repaired regulators should be carefully tested to ensure proper operation. 2-1