Two-handed button is a common safety starting device, commonly seen in punching press, press, cutting machine and other equipment; The purpose is to force operators to leave the dangerous area with their hands when driving the machine, so as to avoid contact with dangerous moving parts and cause safety accidents.

Standard theory of two-handed control

Two-handed control is not a simple two-button control, it is actually a specific relevant standards can refer to. ISO 13851 (GB/T 19671-2022 Mechanical Safety two-handed control device design and selection principles) specifies three types of two-handed control, respectively Type I, Type II and Type III, for different safety requirements, in order to be suitable for different scenarios.

When the two-handed control is required to achieve the safety level of PLc above ISO 13849-1 (GB/T 16855.1), the two-handed control device of Type III must be used, and its functions must meet the three main points:

Continuous operation with both hands is required to release either one or two buttons to terminate the output immediately
The time difference between the two hands is less than 0.5 seconds. If the time exceeds this time, release the two hands button and press it again
The output can only be triggered again after both buttons have been released (i.e. releasing only one button and pressing it again will not perform the output); In addition, for Type IIIC two-handed control devices (corresponding to PLe security level), there are also dual-channel and contact fault detection requirements

Combined with the above requirements, two-handed buttons usually need to be used with a special two-handed button controller (two-handed button safety relay). In addition to the safety function requirements of two-handed control on a device, there are often emergency stop, safety door, safety grating and so on. For complex applications with more requirements for safety functions, programmable safety controllers can be used, such as our PNOZ multi series safety controllers. For simple applications, such as only one emergency stop and two-handed control, it is generally to match a safety relay to the emergency stop, and then through wiring to achieve the logic control between the emergency stop and two-handed button.

A new solution for simple applications

For simple two-handed control applications, there is now a more flexible and efficient option – the modular safety relay MyPNOZ. This is a security solution that can be “tailored” to the needs of the user.

With myPNOZ Creator, an online configuration tool, users can quickly, intuitively, and accurately configure the security functions they need, perform simulation to verify the logical results, and export the hardware configuration table or even the wiring reference with one click. Compared with the previous single function safety relay, it greatly saves the time of selection and learning, improves efficiency and saves cost.

Summary of advantages:

Easy to operate, flexible, modular safety relays with internal combinatorial logic
Easy-to-use myPNOZ Creator comes with a logical editor, emulation, and documentation
Pay-as-you-go: Modules can be customized
Customers receive products that are individually assembled, configured, and tested, ready directly for commissioning
No software required (programming or configuration)

Custom myPNOZ for two-hand controlled air beer machines

A simple two-handed control of the air beer machine, generally only involves the emergency stop, two-handed control or a safety door safety function requirements, next to show you the specific customization process of myPNOZ.

With myPNOZ Creator, you can select emergency stop, two-hand button, safety door, and safety output by clicking the mouse to complete the corresponding hardware configuration.

Head module yh1: emergency stop

Input module yi1: Type IIIC two-handed button control, security door

Output module yo2: Security output *3

Logic: Three safety functions “and” logic, release two-handed button, press emergency stop or open the safety door will immediately cut off the safety output

The safety logic results of two-handed button pressing or emergency stop are verified by simulation.
Click “Display Hardware Information” to view the technical details of each hardware module.
Through the connection reference quickly understand the connection mode to improve the drawing efficiency.
Export the PDF file on the “Order Summary” page to save all the above configuration information and connection modes.