Best Two Hand Control Safety Relay Solutions for Industrial Settings
Two-hand control safety relays are critical components in machine guarding, ensuring operators must use both hands to initiate or continue dangerous operations. This article reviews top two-hand control safety relay options from trusted brands, comparing features, voltage ratings, contact configurations, and mounting styles to help engineers and facilities managers select the right device for compliance and reliable operation. The selections below focus on DIN-rail compatible press-control units and safety relays that support two-hand control with reliable enabling contacts.
| Product | Brand | Key Features |
|---|---|---|
| Siemens 3TK28 34-2AB20 Safety Relay Press Control Unit | SIEMENS | Two-hand safety control, 24VAC, 2 NO enabling contacts, spring loaded terminals, 45 mm width |
| [2-Pack] DC 12V Relay Module 2-Channel | Valefod | Two-channel control, opto-isolation, high/low level trigger, NO outputs, max 10A AC/10A DC |
| Siemens 3TK28 34-1AJ20 Safety Relay Press Control Unit | SIEMENS | Two-hand safety, 115VAC, 2 NO enabling contacts, press-control |
| Siemens 3TK28 34-1AB20 Safety Relay Press Control Unit | SIEMENS | Two-hand safety, 24VAC, screw terminals, 2 NO enabling contacts |
| SICK RLY3-HAND100 | Sick | Two-hand control with application diagnostic output, 24 VDC, 2 enabling paths |
Siemens 3TK28 34-2AB20 Safety Relay Press Control Unit
The Siemens 3TK28 family represents compact press-control safety relays designed for two-hand operation. The 34-2AB20 model uses a 24VAC supply and includes two normally open enabling contacts, suitable for enforcing two-handed control at the machine perimeter. A sturdy 45 mm width allows integration into panel layouts with standard DIN rail mounting options and screw or spring terminal connections, depending on variant. This unit emphasizes reliability in control circuits where both hands must be engaged to proceed, helping meet ISO 13849 or EN 574 requirements when properly integrated with safeguarding devices and restart interlocks.
Siemens 3TK28 34-1AJ20 Safety Relay Press Control Unit
This 34-1AJ20 variant operates with a 115VAC supply, delivering two normally open enabling contacts for two-hand control. Like other 3TK28 units, it adheres to strict safety control principles by requiring simultaneous operator actions to release a dangerous function. Its screw-terminal configuration facilitates secure wiring, with a compact 45 mm width for flexible panel integration. It is a solid option when existing 115V control circuits are in place and a higher voltage operation is preferred for specific machinery configurations.
Siemens 3TK28 34-1AB20 Safety Relay Press Control Unit
The 34-1AB20 model mirrors the 24VAC variant with screw terminals and two NO enabling contacts, making it compatible with low-voltage control circuits common in modern automated lines. Its design emphasizes quick wiring and robust operation under demanding industrial conditions. This unit serves well in systems that require straightforward two-hand interlock with a compact footprint and a focus on dependable safety signaling in automated cycles.
SICK RLY3-HAND100 Two-Hand Safety Relay
The SICK RLY3-HAND100 provides a diagnostic output and monitoring for external devices, along with two enabling current paths and a 24 VDC supply. This configuration supports more complex safety circuits, enabling additional monitoring points that can indicate faults or misalignment in interlock devices. It is well-suited for high-availability environments where real-time safety status is critical, such as packaging lines or press automation where multiple safety paths must be tracked and maintained.
PILZ 750126 PNOZ s6.1 Safety Relay
The PILZ 750126 PNOZ s6.1 is a multi-channel safety relay designed for two-hand control applications, offering two hand control inputs with configurable NO/NC outputs. The device supports 24VDC operation and is part of a broader range of PILZ safety products renowned for reliability in safeguarding machines and operators. Its modularity and established safety performance make it a preferred choice for systems requiring detailed monitoring and robust fault management across multiple safety circuits.
Buying Guide: Key Considerations for Two-Hand Safety Relays
- Voltage and compatibility: Choose a unit that matches your control voltage (24VAC, 24VDC, or 115VAC) and harmonizes with existing control circuitry and wiring practices. Verify terminal type (screw vs. spring) and mounting style to fit your panel.
- Contact configuration: Ensure the relay provides at least two normally open enabling contacts for genuine two-hand operation. Some models also include additional outputs or diagnostic signals for advanced safety logic.
- Safety standards alignment: Confirm the device aligns with applicable standards (for example, ISO 13849, EN 574, or other regional requirements) and integrates with safeguarding devices like interlocks and emergency stops.
- Diagnostics and monitoring: If uptime is critical, select relays offering diagnostic outputs or fault monitoring (as in SICK RLY3-HAND100 or similar) to quickly detect misalignments or faults in the safety circuit.
- Wiring simplicity and reliability: Look for devices with reliable wiring options, including secure screw terminals or spring-loaded terminals, to minimize loose connections in harsh environments.
- Reliability and brand support: Trusted brands (Siemens, SICK, PILZ) often provide better documentation, spare parts, and integration support, which can reduce commissioning time and long-term maintenance costs.
- Physical footprint: 45 mm wide units are common for DIN-rail panels; verify the overall depth and mounting clearance to ensure compatibility with existing enclosures and adjacent devices.
- Future expansion: If your line may scale, consider modules that support additional safety paths or multi-channel configurations without a complete device swap.
When selecting a two-hand control safety relay, balance immediate safety requirements with long-term maintenance and compliance needs. The highlighted options represent a spectrum of voltage ranges, diagnostic capabilities, and mounting styles to help engineers match precise machine guard strategies with practical installation realities.