⚙️Two-Hand Control Module – ESPE ESRH-3A1B Series

Brand: ESPE | Safety Device for Stamping Presses
Compliant with ISO 13849-1 Category 4 / PL e — A mandatory solution in two-hand control systems, protecting operators from accidents due to incorrect operation.

📘Device Introduction

The ESPE ESRH-3A1B is a specialized safety relay module for control systems requiring operators to press two buttons simultaneously within a very short time interval (typically ≤ 0.5 seconds). This mechanism effectively eliminates unintentional single-handed operations, preventing serious accidents in the hazardous areas of stamping presses, hydraulic presses, industrial robots, and similar machinery.

The module acts as a “safety brain” — continuously monitoring signals from the two pushbuttons, checking for synchronicity, and only allowing machine operation when both hands press correctly according to safety standards. Upon detecting any fault (single-hand press, timing discrepancy, wiring fault, jammed button), the device immediately interrupts the control circuit, stopping the hazardous operation.

✨Key Features

• ✓Complies with the highest safety standards ISO 13849-1 Category 4 / PL e and SIL CL 3 (EN 62061).
• ✓Safety relay outputs 3 NO (Normally Open) + 1 NC (Normally Closed) auxiliary, easy to integrate into the machine's emergency stop circuit.
• ✓Cross-fault monitoring circuit continuously checks for short circuits between input and output channels, detecting potential hazards early.
• ✓Multi-status LEDs (Power, Channel 1, Channel 2, Fault) allow for quick diagnostics of operational status and fault identification on-site.
• ✓Input power protection: Overvoltage and reverse polarity protection enhance device stability and longevity.
• ✓Compact modular design for standard 35 mm DIN rail mounting, suitable for all modern industrial control cabinets.

🔧Application & Operating Principle

In stamping presses, robot loading stations, or high-risk operating stations, the ESRH-3A1B forces the operator to use both hands simultaneously to initiate the machine cycle. This ensures the operator's hands cannot be in the danger zone when the machine's moving parts operate.

Basic Principle:

• ✓Reset Mode: Can be configured for automatic Reset (connect Y1-Y2) or manual Reset (using an external Reset button) depending on the application requirements.
• ✓Normal Operation: When both pushbuttons (connected to S11/S12 and S21/S22) are pressed simultaneously within the allowed time window (≤ 0.5s), the safety relays K1/K2 close, enabling machine operation.
• ✓Fault Detection: If only one button is pressed, or the two buttons are pressed asynchronously (> 0.5s apart), or if there is a short circuit/jammed button fault, the safety relays K1/K2 will not close or will open immediately if already closed.
• ✓Dual-Channel Monitoring: Each pushbutton and its signal line are monitored independently to detect faults like short circuits or contact failures, ensuring the integrity of the safety system.

Implementing this solution helps businesses comply with international safety standards (ISO, EN, JIS), significantly reduce the risk of workplace accidents, and meet strict safety inspection requirements for machinery.

🛠️Installation Guide & Safety Notes

Warning: Always disconnect all power supplies to the machine and control cabinet before attempting installation or wiring. Working with live power can cause severe electric shock or damage the device.

1. Securely mount the ESRH-3A1B module onto a 35mm DIN rail inside the control cabinet.
2. Perform wiring according to the diagram provided in the ESPE technical documentation. Pay close attention to input connections (pushbuttons), output connections (safety relays), power supply, and the Reset circuit (if using manual Reset).
3. Thoroughly double-check all wiring connections before reapplying power.
4. After applying power, check the status LEDs and test the two-hand control function according to the proper safety procedures.

💎Benefits of Using ESRH-3A1B

• ✓Significantly enhances the safety level for operators of presses, stamping machines, and other hazardous equipment.
• ✓Complies with the highest international safety standards (PL e, Cat 4).
• ✓Easy integration into existing control systems without complex programming.
• ✓Durable design, long service life, reducing maintenance and replacement costs.
• ✓Meets mandatory inspection requirements from occupational safety authorities.

Related Keywords: ESPE ESRH-3A1B, Two-Hand Control Module, ISO 13849-1 PL e, safety relay 3NO 1NC, safety relay, press safety device, occupational safety, two-button control, PRESTEC.