SR3D Safety Switching Device – Universal Safety Technology for Combustion Systems

The SR3D is a versatile safety switching device with three secure relay outputs. It is specifically designed for continuous operation in combustion systems and complies with the requirements of EN 50156-1. Certified by Germanischer Lloyd (GL) under approval number 32915-06HH, the SR3D is also approved for maritime applications, such as waste incineration plants on ships.

The SR3D combines multiple safety functions into one device. It monitors emergency stop buttons, sliding protective doors, and light curtains, and also serves as a secure coupling relay. With a safety classification of PL e, Category 4, and SILCL 3, it meets the highest safety requirements. Thanks to its compact width of only 22.5 mm, it can be easily integrated into control cabinets, saving space.

The SR3D offers flexible start options, supporting both automatic and monitored manual start. It operates with a variable power supply (AC/DC 24 V, AC 115 V, or AC 230 V). The maximum switching capacity is 8 A at 250 VAC (ohmic load), ensuring reliable control. The device has three instantaneous safety contacts and an additional signaling output for status monitoring.

For easy installation, the SR3D is available with fixed screw terminals, pluggable screw terminals, or push-in spring terminals in TWIN design. Additional accessories such as pluggable terminal sets and spacers are available to ensure secure and flexible installation.

Technical Data:

Feature:

• Safety function: Emergency stop monitoring, sliding protective door monitoring, light curtain monitoring, secure coupling relay
• Certified according to: EN 60204-1, DIN EN ISO 13849-1, EN 62061, EN 50156-1, EN 746-2, IEC 61508 Parts 1-2 and 4-7, IEC 61511-1
• Approvals: CE, TÜV, GL
• Supply voltage: AC/DC 24 V / AC 115 V / AC 230 V
• Number of safety contacts: 3
• Max. switching capacity of safety contacts: 8 A / 250 VAC (ohmic load)
• Number of signaling outputs: 1
• Number of instantaneous safety contacts: 3
• Number of delayed safety contacts: -
• Start behavior: Automatic start or manually monitored start
• PL, Cat., SILCL (EN ISO 13849-1, EN/IEC 62061): PL e, Cat. 4, SILCL 3
• Width: 22.5 mm

Ordering Information:

• Item No. Fixed screw terminals: 472272 (24 V) / 472271 (115 V) / 472270 (230 V)
• Item No. with pluggable screw terminals: 474272 (24 V) / 474271 (115 V) / 474270 (230 V)
• Item No. with push-in spring connection in TWIN design: 475272 (24 V) / 475271 (115 V) / 475270 (230 V)

Accessories:

• Item No. EKLS4; Set of pluggable screw terminals: 472592
• Item No. EKLT4; Set of push-in spring connections in TWIN design: 472595
• Item No. Spacer for defined minimum distance between two safety relays (see derating): 472596