Product Description
Benefits & Applications
The Siemens 3SB3400-0D is a dual 2NO (Normally Open) auxiliary contact block designed for use with Siemens 3SB3 and SIRIUS ACT pushbuttons, selector switches, and operator devices. With two independent NO contacts in a single compact module, the 3SB3400-0D is ideal for circuits requiring redundant or dual “start” signals, parallel PLC inputs, or multi-channel enable logic.
Its rugged construction, long mechanical endurance, and secure snap-on mounting make it a reliable solution for industrial control panels, automation systems, motor starters, and OEM machinery. Installation is fast and tool-free, allowing technicians and panel builders to expand control circuits without modifying the operator housing.
Typical Applications
- Dual start circuits and multi-channel enable functions
- Redundant PLC input or signaling paths
- Motor control and interlocking logic
- Industrial automation and machine panels
- OEM equipment requiring two NO contacts in a single block
Technical Advantages
- 2 Normally Open (2NO) auxiliary contacts
- Tool-free snap-on mounting for quick installation
- High mechanical and electrical endurance
- Reliable low-current control for PLC inputs and signaling
- Compact modular format suitable for tight control cabinets
- Compatible with Siemens 3SB3 and SIRIUS ACT operator systems
Compatibility Notes
The Siemens 3SB3400-0D works with the following product families:
- 3SB3 modular pushbuttons (metal and plastic)
- SIRIUS ACT pushbuttons and selector switches
- Key switches and emergency stop operators
- Control stations and OEM operator assemblies
If your application requires a compact auxiliary unit that provides two NO contacts, the 3SB3400-0D is the correct Siemens OEM replacement or expansion module.
Frequently Asked Questions
Q: What does “2NO” mean for the 3SB3400-0D?
“2NO” means the block contains two independent Normally Open contacts, both of which close when the pushbutton or switch is activated.
Q: Is the 3SB3400-0D compatible with SIRIUS ACT components?
Yes, it works with SIRIUS ACT operator heads that share the 3SB3 mounting interface.
Q: Can this auxiliary contact be used for PLC input circuits?
Yes. Both NO contacts provide reliable low-level switching suitable for PLC control and signaling.
Q: Can multiple auxiliary contacts be stacked?
Absolutely. Siemens 3SB3 contact blocks can be stacked to create additional NO/NC combinations for advanced control logic.
Q: How does the 3SB3400-0D differ from 3SB3400-0B, 0C, and 0E?
• 3SB3400-0B = 1NO
• 3SB3400-0C = 1NC
• 3SB3400-0D = 2NO (dual NO)
• 3SB3400-0E = 1NO + 1NC (changeover)
