Campbell Scientific CR9000X Measurement and Control System - Manual (Page 110)

Section 3. CR9000X Measurement Details
• The CR9058E has a slower maximum scan rate than the CR9050, but
this is somewhat balanced by the fact that the CR9058E measures all of its
channels simultaneously, as each channel has its own 24 bit sigma delta
analog to digital converter. Conversely, the measurements from the
CR9050(E) are multiplexed sequentially through a single A to D
converter.
3.2.1 CR9058E Supported Instructions
The CR9058E currently supports three CR9000X measurement instructions:
1. VoltDiff (Dest, Reps, Range, ASlot, DiffChan, RevDiff, Settle, Integ,
Mult, Offset)
2. TCDiff (Dest, Reps, Range, ASlot, DiffChan, TCType, TRef, RevDiff,
Settle, Integ, Mult, Offset)
3. ModuleTemp (Dest, Reps, ASlot, Integ)
3.2.1.1 CR9058 setup variances with the CR9050/CR9051E
These instructions operate the same as with the CR9050 with these differences:
• DiffChan must be within 1..10.
• VoltDiff supports these voltage ranges: V2 (+/- 2 Volts DC), V2C (+/- 2
Volts with open channel checking), V20 (+/- 20 Volts DC), and V60
(+/- 60 Volts DC).
• TCDiff will work with the same range settings as the VoltDiff instruction,
but only V2 (no open thermocouple checking) or V2C ( +/-2 volt range
with open thermocouple checking) should be used with TCDiff due to
resolution concerns. When the range is set = V2C, an open circuit will
report an over-range condition to the CR9000X.
• The Settle time parameter is unused.
• The minimum scan interval when using VoltDiff or TCDiff , without
input reversal, for the CR9058E is 1520 microseconds for integration
times under 192 microseconds. If the integration time is greater than 192
microseconds, then the minimum scan interval is 1320 + integration time
(microseconds).
• The minimum scan interval when using VoltDiff or TCDiff , with input
reversal, for the CR9058E is 3880 microseconds for integration times
under 192 microseconds. If the integration time is greater than 192
microseconds, then the minimum scan interval is 3680 + (2 x integration
time) in microseconds.
• If open circuit detection is selected for the 2 volt range (range code =
V2C), add 1520 microseconds to the minimum scan time calculated above.
If an insufficient Scan Interval is set in the program, the CR9000 will
report an error code at compile time.
• The Integ parameter in VoltDiff and in TCDiff (not in ModuleTemp) can
be set to –1, -2, -3, -4, or -5 and the CR9058E will set the corresponding
Sinc filter order to 1, 2, 3, 4, or 5. The integration time will be maximized
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