YHSM-04S-A is a 4-channel leak detection control module designed for YHSP-SA and YHSP-SA-Ex leak point sensors, supporting up to four sensors. It provides real-time leak monitoring, LCD status display and user-adjustable sensitivity. Relay outputs include two contacts per channel and four common contacts. RS-485 (Modbus RTU / YH-BUS) supports host system integration. An MTL7760ac Zener barrier is required when connecting YHSP-SA-Ex in an intrinsically safe system.


YHSM-04S-A: A 4-Channel Control System for Integrated Management of Multiple Detection Points
Separate and Manage Solvent & Oil Leak Detection Zones by Channel
For sites with multiple detection points, YHSM-04S-A supports four-channel leak monitoring and host system integration. YHSM-04S-A 4-Channel Leak Detection Control Module connects up to four YHSP-SA or YHSP-SA-Ex leak point sensors for organic solvents and oils. It provides LCD monitoring, adjustable channel sensitivity and NO / NC relay outputs, with RS-485 communication for PLC, DCS and SCADA systems.
⚡️ 4-Channel Leak Monitoring & Alarm Output
• Supports up to four leak point sensors and provides NO / NC relay outputs for leak alarm signaling.
• Provides real-time leak monitoring and control through one 4-channel module.
🔗 Compatible Sensors & System Configuration
• Designed for YHSP-SA and YHSP-SA-Ex leak point sensors for organic solvents and oils.
• An MTL7760ac Zener barrier is required for an intrinsically safe system using YHSP-SA-Ex.
🖥️ Integrated LCD Monitoring & Field Configuration
• View operating status and settings on the LCD (60×33mm).
• Adjust sensitivity for each channel to match site conditions.
⚙️ Per-Channel / Common Contacts & Monitoring Integration
• Provides 2 relay contacts per channel and 4 common contacts for alarm and control integration.
• Supports RS-485 communication with Modbus RTU and YH-BUS protocols for integration with PLC, DCS and SCADA systems.
"From four-channel leak monitoring to relay outputs and host system integration,
YHSM-04S-A supports up to four compatible point sensors for organic solvent and oil leak detection."
| Model | Type | Detection Targets |
| YHSP-SA | Electronic Leak Point Sensor | For Solvent & Oil | Organic solvents and oils. (Up to 4 compatible sensors per module) |
| YHSP-SA-Ex | Intrinsically Safe Electronic Leak Point Sensor | For Solvent & Oil; MTL7760ac Zener barrier required |
| Item | Specification |
| Model | YHSM-04S-A (4-Channel Leak Detection Control Module) |
| Number of Channels | 4 Channels |
| Supported Sensors | YHSP-SA / YHSP-SA-Ex Leak Point Sensors |
| Sensor Capacity | Up to 4 Sensors |
| Detection Method | Level Shift |
| Display | 60 × 33 mm LCD Status Display |
| Power Input | DC 24 V (±10%) |
| Power Consumption | Max. 3 W |
| Power Indicator | Power status indicator (PWR) |
| Alarm Output | • Relay Outputs (NO / NC) for leak alarm signaling • 2 relay contacts per channel and 4 common contacts |
| Communication | RS-485 (Modbus RTU / YH-BUS); 2-wire interface |
| Baud Rate | 9,600 / 14,400 / 19,200 / 38,400 / 57,600 / 115,200 bps |
| Maximum Communication Distance | Up to 1,200 m depending on cable type |
| Operating Temp / Humidity | -20 to +60 °C / 10 to 90% RH (non-condensing) |
| Storage Temperature | -30 to +70 °C |
| Materials | ABS, PC, Aluminum |
| Mounting | Panel Mount |
| Dimensions (W×H×D) | 94 × 178 × 32 mm |
| Weight | Approx. 500 g |
| Key Functions | • Sensor capacity: up to four YHSP-SA or YHSP-SA-Ex leak point sensors • LCD monitoring: integrated viewing of settings and status via LCD (60×33mm) • Sensitivity adjustment: user-adjustable settings for each channel • External communication: RS-485 (2-wire) interface to PLC, DCS and SCADA systems • Protocols: Modbus RTU and YH-BUS (proprietary protocol) • Intrinsically safe system: MTL7760ac Zener barrier required for YHSP-SA-Ex • Relay contacts: 2 contacts per channel and 4 common contacts |
We confirm applicability and recommend solutions based on your target liquid and site conditions.
Setting the trusted standard for liquid leak detection in industrial facilities.