html{display:none} SEL-3505/3505-3 Real-Time Automation Controller (RTAC) | Schweitzer Engineering Laboratories


Real-Time Automation Controller (RTAC)

Suitable for use in utilities and industrial environments, the SEL-3505 Real-Time Automation Controller (RTAC) is a lower-voltage version of the SEL-3530 RTAC. The SEL-3505 RTAC is compact and delivers all the standard features of an RTAC, making it an excellent option for protocol conversion and secure communication when space is limited.

RTAC Family Comparison Chart

Starting At

$830 USD

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Low-Cost Protocol Converter—With the RTAC, you can exchange data through DNP3, Modbus, IEC 61850 GOOSE, IEC 60870-5-101/104, LG 8979, SES-92, IEEE C37.118 for synchrophasors, SEL Fast Messaging, and Mirrored Bits communications. The RTAC also allows you to execute output logic for automation, perform math and logic functions, and convert data between protocols.

Dial-Up Engineering Access and SCADA Communications—The RTAC's serial ports, dial-up modem, and high-speed network connection give you several ways to gain secure, remote access.

IED Event Collection With Optional acSELerator Team SEL-5045 Software—By having all of the information from each intelligent electronic device (IED), filtered and processed through the RTAC, you get immediate notification of any issues through the alarms, Sequence of Events logs, and/or email messages. The optional integrated modem in the SEL-3505 expands your communications for SCADA and engineering access.

Time Synchronization—Implement time-code inputs, such as IRIG-B and Network Time Protocol (NTP), to distribute precise time to connected. In the absence of an external time source, use the internal information processor clock to generate IRIG-B for connected devices.

Integrate Power Management With Industrial Control—Provide a powerful gateway between the substation and the factory using EtherNet/IP. This popular industrial protocol facilitates reliable communication between electronic devices in industrial automation systems. Use the RTAC EtherNet/IP adapter to exchange critical data for real-time monitoring, process control, and power system integration.




RTAC How To Set Series

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RTAC How To Set Series

How to Set the SEL Secure Communications System

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How to Set the SEL Secure Communications System

Integrated Security
Make the RTAC the secure access point into your substation or plant using LDAP central authentication, local role-based user authentication, access logs, and secure engineering access. This increases your system security and helps meet regulatory standards.

Simple, Seamless Configuration
Quickly design an integrated automation system that includes protocol conversion, SCADA communications, synchrophasors, time synchronization, data management, and programmable logic. See how easy it is to set up and start using the SEL RTAC with our "How to" video series.

Renowned SEL Reliability and Support
The RTAC is designed and tested to meet or exceed IEEE 1613 and protective relay specifications for harsh environments and to withstand vibration, electrical surges, fast transients, and extreme temperatures. The SEL RTAC operates reliably, even in challenging environments.

Custom Logic
Create your logic solutions in the embedded IEC 61131 logic engine, which comes standard with every automation controller. Build custom user logic and access all system tags, including diagnostics, contact I/O, protocol data, and communications statistics, to provide unparalleled control flexibility.

Concentrate and manage data from new and legacy relays and other IEDs using our extensive set of protocols.


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