Control Performance
© 2017 General Electric Company – All Rights Reserved.
ADTS 405 R/F Mk2 Instruction Manual-English | 105
8.4 Control Performance
8.4.1 Stability
The ADTS 405 Mk2 provides stable pressure values at the outlet ports and continues to
control smoothly without oscillation into volumes of up to 17 litres (1,000 cubic inches) on Ps
and a volume of up to 10 litres (600 cubic inches) on Pt at rates up to 6,000 ft/min. Lower
volumes enable higher rates of change to be achieved.
The following are the figures based on a 40 ppm of Ps full-scale or Qc full-scale over a
bandwidth of 0.1 to 1.5 Hz and using RMS values. Below are shown the two Qc ranges used by
the ADTS 405 Mk2.
8.4.2 Rate Control
The ADTS 405 Mk2 operates in both aeronautical rates and pressure rates, e.g. ft/min and
mbar/min and controls Ps, Pt and Qc parameters in either aeronautical or pressure units.
Table 8-5: Qc, Rate Qc and EPR Performance Expressed in Pressure Units
Parameter
Differential (Qc)
1000 kts
Differential (Qc)
850 kts
Rate Qc
EPR
Units
mbar diff
mbar diff
mbar/min
-
Maximum Range
a
a. Pressures below 35 mbar absolute and the peak rates of change are available but subject to the use of a
suitable vacuum pump.
-1352 to 3377
-1352 to 2700
10,000
0.1 to 10
Calibrated or
Standard Range
a
-1320 to 2500
-1320 to 1700
200
0.1 to 10
Accuracy
b
b. Accuracy, (expanded uncertainty K=2); includes non-linearity, hysteresis and repeatability over full
temperature range, 12 months drift and calibration standard uncertainty.
RSS of Ps and Pt
RSS of Ps and Pt
c
c. The accuracy figures stated assume that the auto-zero function is enabled.
±1%
Better than 0.005
Resolution
0.01
0.01
0.01
0.001
Table 8-6: Controller Stability
Channel
Pressure Range
Controller Stability
Ps
1,355 mbar (40 inHg)
±0.038 mbar (±0.0011 inHg)
Qc
1,700 mbar (50 inHg)
±0.045 mbar (±0.0014 inHg)
Qc
2,500 mbar (74 inHg)
±0.070 mbar (±0.0021 inHg)
