This equipment is used for testing AC and DC generators. The unit is mounted on a steel skid with blower motor, drive motors and motor starters. The control panel includes switches, meters and connectors. The unit is designed to operate on: 220/440 vac 50/60 HZ, 3 phase power. But may be modified and up graded for other service on request.
Output and Operational Characteristics
Type of test performed Tests AC & DC generators under load at rated RPM
Frequency range (measurement) 350 to 1000 HZ (AC)
AMP Range DC 0-600 AMPS
Type or indicator meter reading
Tachometer range: dual scale, 900 to 12.000 RPM
Voltmeter range 0 to 30 volts
Reversing switch Clockwise and Counter clockwise control
Low speed output: 2350 - 9000 RPM High speed output: 3000 - 11.500 RPM
Note: Speeds up to 18000 RPM on special request.
Motor assembly 70/105 HP varidrive
Drive motor constant speed 1200 RPM Elapsed time meter
Wattmeter range 0 to 7. KW and 0/30 KW Starter: Size 4: 110 vac, 50/60 cycle, 3 phase.
Introduction and General Description
1-2 The following contains descriptive data and operation and maintenance instructions for the Model AGT Aircraft Generator Test Stand, USAF Type A2,
1-3 General Information
1-4 Purpose and Capabilities The aircraft generator test stand is designed to test the operation and performance of 28-volt and 120-volt d-c genera-tors and 120-volt, 350 to l00 hertz, single-phase, a-c generators which are used in aircraft electrical Systems. Skids are provided on the frame to permit movement of the unit from one site to another. The unit is manufactured in accordance with Specification MIL-T-6333A.
1-5 General Description The generator test stand consists of a variable speed drive with related electric drive motor and a speed actuator or changer; a control panel to monitor and control operation; a load bank with resistive load units, cooling fan and contactors; and electric motor-driven blower with duct work for generator cooling; Contactors are pro-vided for motor starting as well as current trans-formers and circuit breakers for circuit protection. Components are supported and located on the welded steel, cabinet type frame which is provided with skids for transportation. Removable panels are provided for access to enclosed components.
1-6 Variable Speed Drive The variable speed drive is a reversible, motor-driven variable speed transmission contained in a cast iron housing mounted on the frame. The drive is a double belt type operating through four variable pitch pulleys, two on the lower drive motor shaft and two on the upper intermediate shaft. Gearing connects the inter-mediate shaft to high and low speed output shafts which are located at the generator mounting faces. The front (high speed) position range is from 3000 to 11600 rpm and the rear (low speed) position range is from 2350 to 9000 rpm. The speed of the output shafts with speed ratios of 6.21 and 4.92 to 1, is varied by changing the pitch diameter of the pulleys as regulated by the speed changer. Output shaft rpm is read on the tachometer at the control panel.
The drive is a variable speed unit is powered by a 70/105 horse power electric motor.
Generator test ratings 28 VDC to 600 amps, 120 VDC to 300 amps, and 120 Vac single-phase, 350 to 1000 hertz to 30 KW
Input Power requirements 220/440 Vac at 232/116 amps,
50/60 hertz, 3 phase
Variable Speed Drive
Make U.S. Electrical Motors
Type VEU-GSDT with double belt, variable pitch sheave
Low speed range 2350 to 9000 rpm
High speed range 3000 to 11600 rpm
Mounting face lO" B.C. (AND20007), drive type
Drive Speed Actuator
MakeU.S Electrical Motors
TypeRemote control, motor
Motor ratingSingle phase, constant speed, reversible
MakeU.S. Electrical Motors
Type Constant speed, reversible, 6 pole
Power requirements 220/440 Vac, 50/60 hertz, 3 phase
Generator cooling blower
Type Turbo-compressor, centrifugal
Output 200 cfm at 20 in. H20 pressure
Motor rating220/440 Vac, 50/60 HZ, 3 phase, 1 hp, 3450 rpm
Load bank cooling fan 1/20 HP, 3000 rpm, 115 Vac single phase, 8 in. dia blade.