Configured for multi-device serial data exchange in STARDOM control architectures, the Yokogawa NFLR121-S50 (NFLR121 Serial Communication Module) provides direct physical/electrical execution.
The module incorporates channel-to-channel isolation and galvanic barriers between internal backplane logic circuits and external RS-422/RS-485 serial ports. Integrated surge protection and noise filtering networks prevent electrical transients from degrading data streams transmitted across multipoint communication lines. Serial-to-parallel data conversion firmware operates deterministically alongside analog processing loops (such as 4-20 mA HART loop protocol gateways) to maintain synchronization and prevent communication dropouts across dense control networks.
Frequently Asked Questions
Q: Can the two serial ports on the NFLR121-S50 be configured independently for different communication protocols?
A: Yes, each RS-422/RS-485 port operates independently, allowing distinct baud rates, parity settings, and duplex modes (half-duplex or full-duplex) to be assigned per channel.
Q: What termination requirements apply when configuring Port 1 or Port 2 for RS-485 multipoint networks?
A: A 120 ohm line termination resistor must be installed across the physical Rx+/Rx- or Tx+/Tx- differential pairs at the two extreme physical ends of the RS-485 bus to eliminate signal reflections.
Field Installation Guidelines
Insert the NFLR121-S50 module into the designated base rack slot of the STARDOM controller, pressing firmly until the retention latch locks into the chassis. Route twisted-pair shielded cables for RS-422/RS-485 bus connections, ensuring signal wiring maintains a minimum 150 mm separation from high-voltage AC lines. Connect outer cable shields to the nearest cabinet protective earth (PE) grounding bar using low-impedance copper conductors. Maintain cabinet ambient temperature between 0 and 55 deg C to ensure stable transceiver performance.
