Communication Management Modules

Industrial RS485 communication hubs that expand one master RS485 link into four or eight independently isolated slave branches, combining automatic baud-rate adaptation, branch isolation, surge protection, and status indication for reliable field-device networking in power and automation cabinets.

Product Capability

A robust MSCR900 Series RS485 hub platform that distributes one master bus to multiple isolated field branches while improving communication reliability, fault containment, and cabinet-level network organization.

Multi-branch RS485 expansion: MSCR902 provides one master RS485 interface plus four slave RS485 branches, while MSCR903 provides one master interface plus eight slave branches for denser field-device networks.
Independent electrical isolation: each RS485 port is optoelectronically isolated, with 2500 VDC isolation stated in the product manual, helping separate branch-side electrical disturbances and ground-potential differences.
Wide communication-rate adaptation: supports automatic baud-rate adaptation from 300 bps to 115.2 kbps, reducing configuration complexity when integrating conventional RS485 field devices.
Half-duplex automatic direction switching: the hub automatically manages RS485 transmit/receive direction, supporting transparent communication distribution without an additional direction-control signal.
Long-distance field communication: the product manual specifies communication distances up to 1.2 km within the stated baud-rate range, subject to cable quality, topology, termination, grounding, and site electromagnetic conditions.
Per-port surge protection: every RS485 channel is specified with 1500 W surge protection, improving resilience against transient disturbances on field communication wiring.
Power-system EMC design: the series is specified to Level 4 requirements for ESD, EFT/burst, and surge immunity under the referenced GB/T standards, supporting demanding secondary-circuit environments.
Visible local diagnostics: PWR, RX, TX, and ERR indicators provide immediate information on power status, data reception, data transmission, and communication abnormality.
Compact DIN-rail installation: 15-36 VDC supply, overall power consumption no greater than 3 W, DIN 35 mm rail mounting, and 22.5 mm / 45 mm widths support standardized cabinet integration.

Customer Value

Simplifies RS485 network architecture and helps prevent one field branch from becoming a single point of failure for the entire communication bus.

Reduce cascading communication failures by separating field-device branches through independent optical isolation instead of connecting all devices directly to one long daisy-chain bus.
Improve troubleshooting efficiency with clearly separated branches and dedicated PWR / RX / TX / ERR indicators, making it easier to distinguish power, traffic, and abnormal-communication conditions.
Simplify cabinet wiring by collecting multiple field RS485 branches into one master connection to an IED, gateway, RTU, PLC, or other host-side RS485 interface.
Scale communication density according to the project: use the narrower four-branch MSCR902 where space and device count are limited, or the eight-branch MSCR903 where more field connections are required.
Improve immunity to field disturbances through port-to-port isolation, surge protection, and Level 4 EMC performance designed for power-system and industrial electromagnetic environments.
Support retrofit projects with transparent RS485 communication, automatic baud-rate adaptation, half-duplex automatic switching, and standard DIN-rail installation without requiring a change to the upper-level communication architecture.
Make network structure easier to standardize across repeated cabinet designs by using a defined master-to-branch communication topology rather than project-specific field-bus splicing.

Product Series

Product series are configured according to users' usage and configuration preferences.

MSCR902

1 master RS485 + 4 slave RS485 branches

Four-channel RS485 hub for compact communication-distribution applications. It provides five completely independent RS485 interfaces in total and uses a 22.5 mm-wide DIN-rail housing.

MSCR903

1 master RS485 + 8 slave RS485 branches

Eight-channel RS485 hub for higher-density field-device networking. It provides nine completely independent RS485 interfaces in total and uses a 45 mm-wide DIN-rail housing.

View technical parameters by product series.

MSCR902 - 4-Branch RS485 Hub

Parameter(MSCR902)	Data(MSCR902)	Remarks(MSCR902)
Product model	MSCR902	MSCR900 Series Communication Network Management Module / RS485 hub.
Master RS485 channels	1	Host-side RS485 interface.
Slave RS485 channels	4	Four independently isolated field branches; five RS485 interfaces in total.
Dimensions	22.5 mm (L) × 88 mm (W) × 102.1 mm (H)	Compact single-width DIN-rail format.
Rated auxiliary supply	15-36 VDC	Common MSCR900 Series supply range.
Baud rate	300 bps to 115.2 kbps, automatic adaptation	Manual states 115.2 kbps-300 bps adaptive operation.
Communication distance	0-1.2 km	Specified for the supported baud-rate range; actual distance depends on cable and site conditions.
Network mode	RS485 half-duplex; automatic direction switching	Transparent transmit/receive direction management.
Interface standard	TIA/EIA-485-A	RS485 physical-layer compatibility.
Port isolation	2500 VDC optoelectronic isolation per RS485 port	Each RS485 port is electrically isolated.
Surge protection	1500 W per RS485 port	Transient surge protection stated in the manual.
Power consumption	<= 3 W	Overall product power consumption.
Protection degree	IP50 enclosure / IP20 terminals	As specified in the product manual.
Terminal capacity	Screw terminals; <= 2.5 mm² conductor	Manual also shows dual-wire terminal capability.
Recommended terminal torque	0.5 N·m	Product overview marking.
ESD immunity	Level 4: ±15 kV air / ±8 kV contact	GB/T 17626.2-2018.
EFT / burst immunity	Level 4: ±4 kV power; ±2 kV input/output	GB/T 17626.4-2018.
Surge immunity	Level 4: ±4 kV line-to-ground; ±2 kV line-to-line	GB/T 17626.5-2019.
Insulation resistance	>= 100 MΩ	Between conductive circuits and earth and between conductive circuits, per GB/T 14598.3-2006.
Dielectric strength	AC 2 kV, 1 min, leakage current 5 mA	Per GB/T 14598.3-2006.
Impulse withstand	1.2/50 µs, ±5 kV, 3 times	Per GB/T 14598.3-2006.
Operating / storage temperature	-25°C to +70°C / -40°C to +70°C	Environmental data stated in the manual.
Flame-retardant rating	UL94 V-0, 750°C / 30 s	Manual flame-retardant requirement.
Installation	DIN 35 mm rail	Standard cabinet mounting.

MSCR903 - 8-Branch RS485 Hub

Parameter(MSCR903)	Data(MSCR903)	Remarks(MSCR903)
Product model	MSCR903	MSCR900 Series Communication Network Management Module / RS485 hub.
Master RS485 channels	1	Host-side RS485 interface.
Slave RS485 channels	8	Eight independently isolated field branches; nine RS485 interfaces in total.
Dimensions	45 mm (L) × 88 mm (W) × 102.1 mm (H)	Double-width DIN-rail format for higher branch density.
Rated auxiliary supply	15-36 VDC	Common MSCR900 Series supply range.
Baud rate	300 bps to 115.2 kbps, automatic adaptation	Manual states 115.2 kbps-300 bps adaptive operation.
Communication distance	0-1.2 km	Specified for the supported baud-rate range; actual distance depends on cable and site conditions.
Network mode	RS485 half-duplex; automatic direction switching	Transparent transmit/receive direction management.
Interface standard	TIA/EIA-485-A	RS485 physical-layer compatibility.
Port isolation	2500 VDC optoelectronic isolation per RS485 port	Each RS485 port is electrically isolated.
Surge protection	1500 W per RS485 port	Transient surge protection stated in the manual.
Power consumption	<= 3 W	Overall product power consumption.
Protection degree	IP50 enclosure / IP20 terminals	As specified in the product manual.
Terminal capacity	Screw terminals; <= 2.5 mm² conductor	Manual also shows dual-wire terminal capability.
Recommended terminal torque	0.5 N·m	Product overview marking.
ESD immunity	Level 4: ±15 kV air / ±8 kV contact	GB/T 17626.2-2018.
EFT / burst immunity	Level 4: ±4 kV power; ±2 kV input/output	GB/T 17626.4-2018.
Surge immunity	Level 4: ±4 kV line-to-ground; ±2 kV line-to-line	GB/T 17626.5-2019.
Insulation resistance	>= 100 MΩ	Between conductive circuits and earth and between conductive circuits, per GB/T 14598.3-2006.
Dielectric strength	AC 2 kV, 1 min, leakage current 5 mA	Per GB/T 14598.3-2006.
Impulse withstand	1.2/50 µs, ±5 kV, 3 times	Per GB/T 14598.3-2006.
Operating / storage temperature	-25°C to +70°C / -40°C to +70°C	Environmental data stated in the manual.
Flame-retardant rating	UL94 V-0, 750°C / 30 s	Manual flame-retardant requirement.
Installation	DIN 35 mm rail	Standard cabinet mounting.

Resources & FAQ

Datatype - Download

Frequently Asked Questions

Q1. What is the main difference between MSCR902 and MSCR903?

The functional architecture is the same: one master RS485 interface distributes communication to independently isolated slave branches. MSCR902 provides four slave RS485 branches and is 22.5 mm wide; MSCR903 provides eight slave branches and is 45 mm wide. Choose primarily according to the required number of field branches and available DIN-rail space.

Q2. Do I need to manually set the baud rate or RS485 transmit/receive direction on the hub?

The MSCR900 Series is specified with automatic baud-rate adaptation from 300 bps to 115.2 kbps and automatic half-duplex direction switching, so the hub itself does not require a separate direction-control signal. The host and field devices must still use compatible protocol settings, baud rate, data format, device addresses, and project communication rules.

Q3. Can the hub prevent one faulty RS485 branch from affecting the other branches?

The architecture is designed to improve fault containment: every RS485 port is optoelectronically isolated and each branch has surge protection, so electrical disturbances on one branch are less likely to propagate directly through the communication network. This does not replace correct RS485 engineering. Cable quality, shielding, grounding, topology, termination, address allocation, protocol configuration, and site EMC conditions must still be verified for the complete system.

The current ODES product category is Communication Management Modules, and the MSCR900 Series instruction manual identifies MSCR902 and MSCR903 as the standard RS485 hub models. The ODES website currently displays MSCR903 as a representative product image. The technical values in this draft are taken from the MSCR900 Series RS485 Hub instruction manual, Version V2.0 dated 2024-07-18. Before website release, quotation, project approval, or ordering, confirm the latest revision of the manual, final model, terminal assignment, communication architecture, field-cable requirements, and applicable certification or type-test scope.