Cameron NUFLO 1141C, User Manual

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Appendix A: Specifications
81
Communications Port (cont’d)
RS-485 ports RS-485 is a two-wire, AC-coupled connection that uses
dedicated terminals that are separate from the RS-232C, with
switch-selectable biasing and termination resistors.
TTL ports The TTL has an 8-pin molex connector, with Tx (3.3V), Rx (3.3V
or 5V), RTS, CTS, GND, earth GND. Firmware-configurable for
normal or inverted orientation.
*DMA (Direct Memory Access) on Rx and Tx of ports A01, A02, and A21.
MVT/RTD Input
The MVT/RTD Multivariable Transducer uses a serial TTL interface to transmit differential pressure,
static pressure, and temperature to the Scanner EFM/RTU. This configuration can be used in Class I,
Division 2 applications.
MVT Inputs
Quantity 2 (1 static pressure and 1 differential pressure )
Accuracy Differential Pressure Accuracy (30 In. H2O): ±0.10%
Differential Pressure Accuracy (200 to 840 In. H2O)
:
±0.05%
Static Pressure Accuracy: ±0.05%
Temperature Performance ±0.25% of full scale over full operating temperature range
Effect on differential pressure
for a 100-psi change in static
pressure Span shift ± 0.01% of reading
Zero shift listed by URL:
Differential Pressure
URL (inches wc)
Static Pressure
URL (psi)
Zero Shift
(% of URL)
30 100 ±0.05%
200 300 ±0.007%
200 500 to 5300 ±0.01%
300 1500 to 5300 ±0.004%
400 1500 to 5300 ±0.004%
840 300 ±0.002%
840 1500 to 5300 ±0.004%
Stability Long-term drift is less than ± 0.05% of URL per year over a 5-
year period.