Woodward AtlasPC, Hardware Manual

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Manual 85586V1 AtlasPC Digital Control, Vol. I
Woodward 65
CJ update time 5 ms
Latency 1 ms for odd channels and 3 ms for even
numbered channels
Failure detection Open wire detection provided for thermocouples
Isolation All input channels are isolated from the rest of
the AtlasPC platform to 500 Vac, however they
are not isolated from each other. The inputs are
differential, with a high impedance between
channels.
CJ accuracy ±3 °C worst case at 25 °C, (±1 °C typical at 25
°C) uncalibrated
±1 °C worst case at 25 °C, (±0.5 °C typical at 25
°C) calibrated
±4 °C over the full temperature range (–40 to
+85 °C) uncalibrated
±2 °C over the full temperature range (–40 to
+85 °C) calibrated
•
Loop power for the analog inputs must be supplied by an external supply, if
needed.
•
4–20 mA, or type J or K T/C is selected in the GAP block software, for each
input. GAP configuration sets input gain via software.
•
Maximum wire size, one 16 AWG (1.5 mm²), or two 20 AWG (0.5 mm²)
wires.
•
Channels 1–10 must be configured in pairs, that is, channels 1 and 2, 3 and
4, etc., must both be configured as 4–20 mA inputs or must both be
configured as thermocouple inputs.
•
Any “unused” channel of a pair, Channels 1–10, must have its input shorted
to prevent measurement errors on the “in-use” channel of the pair.
External loop powered transducers must be individually protected
with a 100 mA fuse on each channel.
RTD/4–20 mA Analog Inputs
Number of channels 4
Input type 100 or 200 Ω 3-wire
Max. input current 24 mA, if configured for 4–20 mA
Max. input resistance 781 Ω , if configured for RTD
RTD range European Curve (Type 385):
100 Ω RTD: 18.49 Ω (–200 °C/–328 °F) to
390.48 Ω (850 °C/1562 °F)
200 Ω RTD: 37.04 Ω (–200 °C/–328 °F) to
533.10 Ω (457 °C/854.6 °F)
American Curve (Type 392):
100 Ω RTD: 59.57 Ω (–100 °C/–148 °F) to
269.35 Ω (457 °C/854.6 °F)
200 Ω RTD: 119.14 Ω (–100 °C/–148 °F) to
538.70 Ω (457 °C/854.6 °F)
Common mode rejection –80 dB minimum for analog inputs
–96 dB typical for analog inputs
–96 dB minimum for RTD inputs
–115 dB typical for RTD inputs
Input common mode range ±11 V minimum
Safe input common mode volt ±40 V minimum
Input
impedance 103 Ω (±1%) for 4–20 mA inputs
Anti-aliasing filter 2 poles at 10 ms
Resolution 15 bits