Eaton Intrinsically Safe High Bandwidth Surge Protection Device with 10kA Surge Current for Industrial Signals
SD07R - Intrinsically Safe Surge Protection for RS-485 & 4-20mA Loops
The SD07R is a high-performance surge protection device designed specifically to protect RS-485, RS-232 communication lines, and 4-20mA process control loops from damaging transient overvoltages and lightning-induced surges. Part of Eaton MTL's trusted SD Series, this module delivers robust protection in an ultra-slim, space-saving package ideal for DIN rail mounting in industrial control cabinets, hazardous areas, and field junction boxes.
- Fire alarm and gas detection systems
- Process I/O and shutdown systems (ESD)
- Thermocouple and transmitter circuits
- SCADA and industrial communication networks
| Feature | Benefit |
|---|---|
| Ultra-slim 7mm width | Maximizes panel density - up to 12 modules per foot of DIN rail |
| 10kA maximum surge current (8/20 µs) | Robust protection against lightning and switching transients |
| < 1ns response time | Instantaneous clamping protects sensitive electronics |
| Fused disconnect / loop isolation | Safe maintenance - pull the fuse to isolate the circuit without removing terminals |
| Dual-channel protection | Protects 2-wire and 3-wire loops in one module |
| DIN rail mountable | Tool-free installation, standard 35mm rail |
| ATEX / IECEx certified | Suitable for hazardous area installations (intrinsically safe) |
| Auto-resetting after surge | No downtime - continuous operation maintained |
| 10-year product warranty | Long-term reliability backed by Eaton MTL |
| Parameter | Value |
|---|---|
| Model | SD07R |
| Nominal voltage (Un) | 7V DC |
| Max continuous operating voltage (Uc) | 7V DC |
| Nominal discharge current (In) | 3kA (8/20µs) |
| Max discharge current (Imax) | 10kA (8/20µs) |
| Response time (tA) | ≤1 nanosecond |
| Bandwidth | 50 MHz |
| Load current rating | 400 mA max |
| Protection modes | Line-to-line, line-to-ground |
| Residual voltage (clamping) | Low clamping voltage for sensitive equipment |
| Operating temperature | -40°C to +80°C |
| Dimensions (H x W x D) | 99mm x 7mm x 99mm |
| Weight | ~56g (0.077kg) |
| Mounting | 35mm DIN rail (EN 60715) |
| Certifications | ATEX, IECEx, CSA, UL (varies by region) |
The SD07R features multistage hybrid protection circuitry combining gas discharge tubes (GDT) and solid-state clamping components. This delivers both high surge handling capacity and ultra-fast response - essential for protecting expensive PLC cards, DCS I/O modules, and field transmitters.
Unlike standard SDX series protectors, the SD series (including SD07R) incorporates a built-in fuse holder. This allows technicians to:
- Isolate the protected circuit without removing wires
- Safely perform loop testing and maintenance
- Protect against fault currents that could damage downstream equipment
The SD07R is BASEEFA/ATEX certified as a simple apparatus, meaning it can be installed in Zone 0, 1, and 2 hazardous areas without compromising the intrinsic safety certification of the loop.
At just 7mm wide, the SD07R occupies minimal panel space - a critical advantage for retrofitting surge protection into existing cabinets where space is at a premium.
| Application | Specific Use Case |
|---|---|
| Fire & Gas Systems | Addressable loops, detector circuits |
| Process Control | 4-20mA analog inputs from pressure/temperature transmitters |
| Emergency Shutdown (ESD) | Safety PLC digital inputs |
| Communication Networks | RS-485, RS-232, Modbus, Fieldbus |
| Telemetry & SCADA | Remote terminal unit (RTU) protection |
| Hazardous Area Barriers | Downstream of zener barriers or galvanic isolators |
| Model | Description |
|---|---|
| SD07R | 7V surge protector with fused disconnect |
| SD16R | 16V version for 4-20mA loops |
| SD32R | 32V version for higher voltage signals |
| SD55R | 55V version |
| SD07X | 7V version without fused disconnect (standard SDX series) |
Cross-reference: Compatible with and replaces legacy MTL SD07R units. Backward compatible with SD series mounting bases.
- ✅ Genuine Eaton MTL products - factory sealed, full warranty
- ✅ Competitive pricing - volume discounts available
- ✅ Fast global shipping - stock available for immediate dispatch
- ✅ Technical support - application engineering assistance available
- ✅ Bulk/packaging options - inquire for OEM and project quantities
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