DA Form 7468-R at a glance
What it is: DA Form 7468-R is the Engine Generator Set Inspection Checklist; for use of this form see TM 5-694.
A filled-in DA Form 7468-R example: a technician records the visual checks and insulation resistance
How to fill out DA Form 7468-R, box by box
Section A - Customer data
In Section A, fill in 1. Plant/Building, 2. Location, 3. Job Number, 4. Equipment, 5. Circuit Designation and 6. Date (YYYYMMDD).
Fill in 7. Test Equipment Type/Brand and Calibration Date and 8. Tested By.
Section B - Equipment data
In Section B, fill in 9. Manufacturer, 10. Styles/S.O., 11. Voltage Rating and 12. kW Rating.
Fill in 14. Wet Bulb Temperature, 15. Dry Bulb Temperature and 13. Circuit Breaker Size/Interrupting Rating.
Section C - Visual and electrical/mechanical inspection
Under COND, enter A for acceptable; R for needs repair, replacement or adjustment; C for corrected; NA for not applicable.
Section C is Visual and Electrical/Mechanical Inspection; each CHECK POINT has COND and NOTES.
Check: Exterior of Equipment, Equipment Identification, Completeness of Assembly, Bracing, Equipment Rotation, Proper Phase Connections, Check Oil Level, Reference Drawings, Check Fuel Level, Working Clearance, Proper Equipment Grounding, Anchorage, Check Meters/Gauges, All Filters and Vents Clear, Check Equipment Environmental Classification, Check for Provisions of Spill Container, Tightness of Bolted Connections, Verify Governor and Regulator, Check Vibration, Control System, Check Batteries, Check Fuel Filter, Check Alarm Indicators: Proper Color for Each Function, Check Radiator Fluid and Proper System Ground.
17. Insulation resistance
In Section D, Electrical Tests, enter 17. Insulation Resistance for A-GRD, B-GRD, C-GRD, A-B, B-C and C-A.
Polarization index ratio
Enter the Polarization Index Ratio = 10 minute/1 minute for A-GRD, B-GRD, C-GRD, A-B, B-C and C-A.
DC overpotential test
For the DC Overpotential Test, 18. Notes say: 1. Perform 5 measurements at one minute intervals. 2. DC hipot measurements should begin at 20% of maximum test voltage and increase in equal intervals; max DC test voltage = R (2 x nameplate rating) x 1.6, where R = .8 for DC test on installation and R = .6 for DC test after service.
Test measurements should not exceed manufacturer's recommendation.
More rules for DA Form 7468-R
On page 2, Section D - Electrical Tests (Continued) has voltage and current measurements (19.) and 20. Load Tests as a Percentage of Generator Rating: No Load, 25 %, 75 %, 100 % and 110% (Prime Engine Only).
1. Voltage measurement to be made after generator is started and connected to load (can use load bank).
During commissioning of generator sets or any equipment, a representative of the manufacturing company or supplier must be present to witness and/or perform the tests.
Engine generator testing is a very intensive process and requires a 10 to 14 hour day depending on the equipment being commissioned.
Verify all system check points during load changes and record per specified requirements and/or equipment manufacturer; perform and record engine manufacturer's recommended checks and inspections.
Sources
[1] DA Form 7468-R (AUG 2002), Engine Generator Set Inspection Checklist, U.S. Army (the Official source link on this page).