1-10 ARMY TM 9-6115-644-24 AIR FORCE TO 35C2-3-446-12 MARINE CORPS TM 09249A/09246A-24/2 DIFFERENCES  BETWEEN  MODELS. 1-10-1 The differences between models of the generator sets covered in this manual are as follows: a. Model MEP-805A is equipped with a 50/60 Hz generator, 50/60 Hz frequency meter, and 50/60HZ frequency selector switch. b. Model MEP-815A is equipped with a 400 Hz generator and 400 Hz frequency meter. 1-10-2 Performance characteristics for the two models are shown in TABLE 1-2. TABLE 1-2. Performance Charateristics (a). (b) (c) (d) (e) ( f (g) (h) (i) (j) Voltage wave form deviation  factor Single voltage harmonics: Voltage unbalance Phase balance voltage Voltage modulation Voltage regulation Short-term  stability (30 seconds) Long-term  stability (4 hours) Voltage drift (60° F (16° C) in 8-hour period) Dip and rise for rated load Recovery time Dip for low power factor load Recovery time MEP-805A 5%  (max) 2%  (max) 5% of rated voltage  (max) 1% of rated voltage  (max) 1%  (max) 1%  (max) 1% of rated voltage 2% of rated voltage ± 1% (max) 15% of rated voltage (max) 0.5 seconds 30% of no-load voltage (max) 0.7 seconds 85% of no-load voltage MEP-815A 5%  (max) 2%  (max) 5% of rated voltage (max) 1% of rated voltage (max) 1%  (max) 1%  (max) 1% of rated voltage 2% of rated voltage ± 1% (max) 12% of rated voltage (max) 0.5 seconds 25% of no-load voltage (max) 0.7 seconds 95% of no-load voltage 1-9