The Yokogawa SNT501-53 is an Optical ESB Bus Repeater Slave Module used in Yokogawa ProSafe-RS Safety Instrumented Systems (SIS).
It functions as the slave-side optical communication module, working together with a master module (such as SNT401 / SNT411) to extend ESB bus communication via optical fiber. This enables long-distance, high-reliability data transmission between safety controllers and distributed I/O nodes.
The suffix “-53” indicates a specific configuration:
- -5 = Standard type (no explosion protection)
- 3 = ISA G3 environmental rating (-20°C to +70°C)
Technical Specifications
| Parameter | Specification |
|---|---|
| Brand | Yokogawa |
| Model | SNT501-53 |
| Product Type | Optical ESB Bus Repeater (Slave) |
| System Compatibility | ProSafe-RS / ESB bus architecture |
| Function | Optical signal reception & regeneration |
| Pairing Module | SNT401 / SNT411 (Master) |
| Network Type | ESB optical fiber communication |
| Topology | Star / Chain connection |
| Max Connection Stages | 2 stages |
| Transmission Distance | Up to 5 km per segment (up to ~10 km total) |
| Data Rate | Up to 1 Mbps |
| Power Supply | 24 V DC |
| Current Consumption | ~0.5 A |
| Operating Temperature | -20°C to +70°C |
The module ensures stable optical transport of ESB signals, maintaining deterministic communication required in safety systems.
Physical Characteristics
| Item | Specification |
|---|---|
| Dimensions (L × W × H) | Approx. 143 × 130 × 33 mm |
| Alternative Compact Form | 82 × 19 × 25 mm (module-only variant) |
| Weight | Approx. 0.3 – 0.75 kg |
| Mounting Type | Rack / repeater unit (e.g., SNT10D) |
| Structure | Optical repeater slave module |
| Installation | SIS control cabinet |
Recommended Related Models
- Yokogawa SNT401 – Optical ESB Bus Repeater Master
- Yokogawa SNT411 – Advanced ESB optical master module
- Yokogawa SNT10D – Optical repeater rack unit
- Yokogawa SNB10D – Safety node unit
- Yokogawa SEC401 / SEC402 – ESB coupler modules
Popular Yokogawa Models
- Yokogawa SNT501-53 – Optical ESB slave module
- Yokogawa SNT401 – ESB master repeater module
- Yokogawa SNT411 – long-distance optical ESB module
- Yokogawa NFCP100 – communication processor
- Yokogawa CENTUM VP – DCS platform
