Woodward AtlasPC, Hardware Manual

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Manual 85586V1 AtlasPC Digital Control, Vol. I
Woodward 79
Specifications
Utility and Generator PT Voltage Inputs
Input Voltage (Typical) 77, 120, 240/277 Vac, transducers externally
powered.
Max. Input Voltage 300 Vac
Input Current 3 mA maximum
Input Frequency 45—70 Hz
Common Mode Voltage ±450 Vdc minimum
Common Mode Rejection Ratio –63 dB minimum
PT Temp Drift
(Vrange =
70/120/240 Vrms)
–40 to +85 °C Any 40 °C change
Typical (1 σ ): < 0.4 % of Vrange < 0.3% of Vrange
0.28V, 70V scale 0.21V, 70V scale
0.48V, 120V scale 0.36V, 120V scale
0.96V, 240V scale 0.72V, 240V scale
Max (3 σ ): < 1.2 % of Vrange < 0.8% of Vrange
0.84V, 70V scale 0.56V, 70V scale
1.44V, 120V scale 0.96V, 120V scale
2.88V, 240V scale 1.92V, 240V scale
Input Impedance
400 k Ω or greater
Isolation see HAZARDOUS LIVE section above
Utility and Generator CT Current Inputs
Input Current 5 A rms full scale
Max Transient Input Current 7.07 A rms
Input Frequency 45—70 Hz
Common Mode Voltage ±250 Vdc minimum
Common Mode Rejection Ratio –63 dB minimum
Accuracy see PT/CT Accuracy Table
CT Temp Drift
(FullScale = 5 Arms) –40 to +85 °C
Any 40 °C change
Typical (1 σ ): < 0.4% or 20.0 mA < 0.3% or 15.0 mA
Max (3 σ ): < 1.2% or 60.0 mA < 0.8% or 40.0 mA
Input Impedance
0.030 Ω
Isolation see HAZARDOUS LIVE section above