The ABB PLUTO B42 safety relay (order code 2TLA020070R1400) is a high-performance programmable safety controller with an integrated AS-Interface (AS-i) master. Designed for machinery safety applications up to SIL 3 according to IEC 61508 and PL e per ISO 13849-1, this relay simplifies the implementation of safety functions in automated systems.
Integrated AS-i master for direct connection to AS-Interface safety slaves.
8 safe digital inputs and 4 safe solid-state outputs.
Two relay outputs rated 6 A each.
Certified for emergency stop, light curtains, two-hand controls, and safety gates.
Configuration via Pluto Manager software with function block diagram.
Built-in diagnostics and status LEDs.
Supply voltage: 24 VDC (nominal). Inputs: 8 safe inputs, PNP type, 24 VDC. Outputs: 4 safe PNP transistor outputs (0.5 A each), plus 2 relay outputs (6 A). Safety integrity level: SIL 3 (IEC 61508), PL e (ISO 13849-1). AS-i master specification: M4, supports up to 62 AS-i slaves. Operating temperature: 0°C to 55°C. Dimensions: 110 mm x 45 mm x 115 mm. Mounting on DIN rail EN 60715.
The PLUTO B42 eliminates the need for a separate AS-i gateway. It directly communicates with AS-i safety components such as emergency stop buttons, guard door switches, and light curtains. The integrated master supports both standard and safety slaves, reducing wiring complexity and improving system responsiveness. Configuration includes automatic address assignment and safe data exchange via the AS-i Safety at Work protocol.
Typical applications include press brakes, packaging machinery, robotic cells, and conveyor systems. The relay's 8 safe inputs can monitor multiple dual-channel devices, while the 4 safe outputs provide control signals to contactors or safety valves. Use the logic configurable within Pluto Manager to create interlocks, time delays, and bypass functions without additional external relays.

Mount the device on a standard 35 mm DIN rail. Connect 24 VDC power to terminals A1 and A2. Wire safety devices to input terminals S1 through S8. Outputs O1 to O4 drive safety contactors. The AS-i interface connects via yellow flat cable on the top terminals. Use the USB or Ethernet port for programming. Download the safety program via Pluto Manager, verify the signature, and perform a function test.
CE marked, UKCA, cULus listed. Complies with Machinery Directive 2006/42/EC, EMC Directive 2014/30/EU, and RoHS. Approvals: TÜV Rheinland functional safety certificate. Suitable for applications up to PLe and SIL 3 when properly integrated into a safety-related control system.
The base unit includes terminal blocks. For programming, use Pluto Manager software (free download) and a standard USB cable (Type A to Mini-B). Optional accessories: AS-i power supply unit, addressing device, and termination resistor. The product is available through ABB distribution channels.



