SEL-2902 RJ45 to DB-9 Adapter Panel

Easily adapt the SEL computer platform's RJ45 serial ports to DB-9 connectors

Key Features and Benefits

Retrofit Applications: Retain existing serial cables and transceiver installation when upgrading an SEL-3530 Real-Time Automation Controller (RTAC) or SEL-2020/SEL-2030/SEL-2032 Communications Processor to the SEL-3350 Automation and Computing Platform and SEL-3355 Automation and Computing Platform.
Flexible Mounting Options: Use rack-mount, surface-mount, or DIN-rail mounting options to support several different types of installations.
Secure Transceiver Mounting: Provide solid mounting for SEL serial transceivers when used with the SEL-3350 and SEL-3355.
Cable Management: Use the included rack-mount brackets to allow the use of existing cable management solutions.

Product Overview

The SEL-2902 is a 2U rack-mountable adapter panel designed to convert RJ45 serial ports to DB-9 connectors. It facilitates the integration of older serial equipment with modern SEL computer platforms.

Figure 1: SEL-2902 2U Adjustable Rack Mount, Front. This view shows the front panel with 16 built-in RJ45 ports, labeled 1 through 16. The SEL logo and product name are visible.

Figure 2: SEL-2902 2U Adjustable Rack Mount and Surface Mount, Rear. This view shows the rear of the unit, featuring 16 built-in DB-9 female ports, labeled 1 through 16. Rack-mount brackets for cable management are also depicted.

Figure 3: SEL-2902 2U 19-Inch Adjustable Rack Mount, Top. This view illustrates the top of the rack mount assembly, highlighting its adjustable depth feature, which can be set from 7 to 11 inches.

Connector Pinout Diagram

Table 1 details the pinout mapping between the SEL-3350 Series EIA-232 signals, the RJ45 connector, and the DB-9 connector.

SEL-3350 Series Signal (EIA-232)	RJ45 Connector	DB-9 Connector
-IRIG-B out (GND)	1	6
+5 Vdc^a	2	1
+IRIG-B out	3	4
Signal Ground (GND)	4	5
Receive Data (RXD)	5	2
Transmit Data (TXD)	6	3
Clear to Send (CTS)	7	8
Request to Send (RTS)	8	7
SHIELD	SHELL	SHELL

^a Software-enabled on the SEL-3500 series.

Grounding

Connect all chassis grounding terminals labeled GND on the rear panel to a rack frame ground or main station ground for proper safety and performance. Use 14 AWG (2 mm²) or larger wire, less than 3 m (10 ft) in length, for this connection. All ground terminals connect directly to the internal chassis ground of the SEL-2902.

Applications

SEL-2020, SEL-2030, SEL-2032, and SEL-3530 Retrofit Application

The adapter panel, with its adjustable-depth rack-mount option, can be configured between 7 and 11 inches in depth to match existing SEL-2020, SEL-2030, SEL-2032, or SEL-3530 installations. This compatibility allows existing communications cables with DB-9 connectors to be retained. An SEL-CA605 cable or equivalent shielded Ethernet patch cable can be used to connect the adapter panel RJ45 port to the ports on an SEL-3350, as depicted in Figure 4, or an SEL-3355 that utilizes optional SEL-3390S8 Serial Adapter Cards.

Figure 4: SEL-2902 Installed Below an SEL-3350, Using the Ethernet Cable Kit (915900638) and Retaining Existing Serial Cables and Transceivers With a DB-9 Connector. This illustration shows the physical connection setup between the SEL-3350 and the SEL-2902 adapter panel, highlighting the use of Ethernet and serial cables.

SEL-3350 and SEL-3355 and Secure Mounting of Transceivers

Securely mount the adapter panel using the surface-mount option to a solid surface, a 19-inch rack-mount panel, or DIN rail via the optional DIN-rail mounting kit (915900639). Connect serial transceivers with a DB-9 male connector to the DB-9 port. An SEL-CA605 or equivalent shielded Ethernet patch cable can connect the RJ45 port to the SEL-3350 or SEL-3355 ports.

Installation

Unit Location and Placement

For reliable operation, install the SEL-2902 following these guidelines. Mount the SEL-2902 with the SEL-3300 series device in a sheltered indoor environment (e.g., a building or enclosed cabinet) that adheres to the unit's temperature and humidity ratings (refer to Specifications on page 10). The unit is rated as Installation/Overvoltage Category II (at <5 km altitude) and Pollution Degree 2. These ratings permit indoor mounting or mounting in an outdoor (extended) enclosure, provided the unit is protected from direct sunlight, precipitation, and wind pressure, even if temperature and humidity are not controlled. For safety, install the unit within a suitable fire/electrical/mechanical enclosure.

To achieve optimal EMI and EMC performance, the SEL-CA605 cable or equivalent shielded Ethernet patch cable connecting the SEL-3300 series device to the SEL-2902 RJ45 port should not exceed 2 meters (6.6 feet) in length.

Mounting Bracket Adjustment

The adjustable-depth mounting option is shipped at a default depth of 8 inches, as shown in Figure 5. The depth can be adjusted in 1-inch increments from a minimum of 7 inches to a maximum of 11 inches, as illustrated in Figure 6.

To adjust the depth: Remove four screws from the side and eight screws from the bottom, as indicated by arrows in Figure 7. Move the adapter panel to the desired depth, as shown in Figure 8. Reinstall the screws, as shown in Figure 9. Torque all screws to 12 in-lb.

Figure 5: Adjustable Rack Mount Configured to Depth of 8 Inches. This image shows the rack mount bracket set to its default 8-inch depth.

Figure 6: Adjustable Rack Mount Configured to Depth of 11 Inches. This image displays the rack mount bracket extended to its maximum 11-inch depth.

Figure 7: Remove Screws. This illustration visually guides the user on which screws to remove from the side and bottom of the rack mount bracket to adjust its depth. Orange arrows indicate screw locations.

Figure 8: Move to Desired Depth. This diagram shows the adapter panel being slid within the rack mount bracket to achieve the selected depth.

Figure 9: Reinstall Screws (11-Inch Depth Configuration Shown). This illustration depicts the process of reinserting screws after the adapter panel has been moved to the desired depth, specifically showing the 11-inch configuration.

Surface Mounting

To mount the adapter panel using the surface-mount option, refer to the dimensions shown in Figure 14 and drill holes no larger than 3/16 inch (5 mm).

Figure 10: Surface-Mount Option. This image shows the SEL-2902 adapter panel mounted onto a flat surface.

DIN-Rail Mounting

To utilize the optional DIN-rail mounting kit (915900639), snap the two DIN-rail clips onto your DIN rail. Align the DIN-rail clips with the center of the adapter panel mounting ears, as shown in Figure 11. Thread the included #8 plastic screw through the hole and into the DIN-rail clip. Torque the screw to 12 in-lb after it is fully seated.

Figure 11: DIN-Rail Mounting Example. This illustration demonstrates the SEL-2902 adapter panel attached to a DIN rail.

Cable Management

Each SEL-2902 configured with the adjustable-depth bracket includes accessory mounting ears and hardware, as shown in Figure 12. The mounting ears can be installed by torquing screws to 12 in-lb after the adapter panel is in place. Use third-party cable management brackets compatible with 2U, 19-inch rack-mount holes.

Figure 12: Installed Mounting Ears. This image shows the accessory mounting ears attached to the sides of the SEL-2902 adapter panel.

Dimensions

Figure 13: Adjustable Rack-Mount Adapter Panel. This technical drawing provides detailed dimensions for the adjustable rack-mount configuration, including height, width, depth, and mounting hole specifications. The adjustable length is noted as 7.00 - 11.00 inches [177.8 - 279.4 mm].

Figure 14: Surface-Mount Adapter Panel. This technical drawing provides detailed dimensions for the surface-mount configuration, including overall size and mounting hole patterns.

Specifications

Compliance

Designed and manufactured under an ISO 9001 certified quality management system.
47 CFR 15B Class A: This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when operated in a commercial environment.
UL Listed: Meets U.S. and Canadian safety standards (File E220228; NRAQ).
CE Mark
RoHS Compliant

General

Connectors: Female DB-9, Shielded RJ45 Jack
Power Requirements: None
Dimensions: See Figure 13 and Figure 14.
Relative Humidity: 5 to 95% noncondensing
DB-9 Jack Screw Torque: 6 in-lb
Operating Temperature Range: -40° to +85°C (-40° to +185°F)
Ground Screw: #6 Crimp Ring Terminal is Recommended. Warning: When using stranded wire, use crimp ferrules to safely capture all wire strands before assembling and attaching the plug or ground wire.
Insulation Ratings: 300 V, 90°C (194°F), minimum

Wire Material

Material: Copper
Size: 12–18 AWG (4.00–0.75 mm²)
Length: <3.0 m (<9.8 ft)
Tightening Torque Min/Max: 0.9–1.36 Nm (8–12 in-lb)

Mounting Brackets

Tightening Torque Min/Max: 2–4 Nm (18–35 in-lb)

Type Tests

To ensure protection-level EMI and EMC performance, type tests were performed using shielded serial cables with the shield grounded at both ends of the cable.

Electromagnetic Compatibility Immunity

Conducted RF Immunity:

IEC 60255-26:2013
EN 60255-26:2013 § 7.2.7
IEC 61850-3:2013
EN 61850-3:2014
EN 55011:2009+A1:2010
EN 55022:2010+AC:2011
EN 55032:2015 + A11:2020
CISPR 11:2009+A1:2010
CISPR 11:2015 + A1:2015 + A2:2019
CISPR 22:2008
Canada ICES-001 (A)/ NMB-001 (A)
CISPR 32:2015 + A1:2019
ANSI C63.4:2014
CSA CISPR 11:19
ICES-001, Issue 5
47 CFR Part 15.107
47 CFR Part 15.109

Other type tests and standards are inherited from the SEL-3350 Automation and Computing Platform and can be found in Section 1: Introduction and Specifications in the SEL-3350 Instruction Manual.

Technical Support

Schweitzer Engineering Laboratories, Inc. welcomes your interest in SEL products and services. For questions or comments, please contact us:

Schweitzer Engineering Laboratories, Inc.
2350 NE Hopkins Court
Pullman, WA 99163-5603 U.S.A.
Tel: +1.509.338.3838
Fax: +1.509.332.7990
Internet: selinc.com/support
Email: info@selinc.com

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