TP48-3-I-NDI DIN Rail Mount 48V DC 3-Wire Intrinsically Safe Surge Protection Device for Industrial Transmitters
The TP48-3-I-NDI is a high-performance surge protection device (SPD) from the Eaton Crouse-Hinds series MTL TP48 range, specifically engineered to safeguard 3-wire field-mounted process transmitters from damaging voltage transients and lightning-induced surges.
Unlike conventional surge protectors that require complex wiring or conduit modifications, the TP48-3-I-NDI installs with unprecedented simplicity — it screws directly into an unused conduit entry of the transmitter, providing robust protection without affecting normal operation. The device resets automatically after each surge event, ensuring continuous, maintenance-free protection.
With ATEX certification for hazardous area installations, the TP48-3-I-NDI is the trusted choice for oil & gas platforms, chemical plants, pharmaceutical facilities, and other explosive atmospheres.
| Code Segment | Meaning |
|---|---|
| TP48 | Series — Surge protection for field-mounted transmitters |
| -3 | 3-wire transmitter configuration |
| -I | ISO thread — 20mm (M20 x 1.5) |
| -NDI | Certified version — ATEX/IECEx approved for hazardous areas |
The "NDI" suffix indicates full hazardous area certification (ATEX/IECEx), while non-NDI versions are for general-purpose applications.
- Direct Transmitter Mounting: Simply screws into an unused conduit entry — no additional wiring, conduit modifications, or expensive extras required
- 3-Wire Protection: Specifically designed for 3-wire field-mounted transmitters, providing complete protection for power, signal, and return lines
- Hazardous Area Certified: ATEX, IECEx, and other international approvals for use in potentially explosive atmospheres (Gas Groups IIA, IIB, IIC; Temperature Class T6)
- High Surge Capacity: Handles impulse ratings of 10kA peak current (8/20µs) and 10kV peak voltage — far exceeding optional transient protection from transmitter manufacturers
- Automatic Reset: Self-resetting after each surge event — no manual intervention or replacement required
- No Signal Degradation: Low impedance design introduces negligible resistance into the loop, preserving signal integrity
- Rugged 316 Stainless Steel Housing: Built to withstand harsh industrial environments, including offshore and marine applications
- 10-Year "No Fuss" Warranty: Backed by Eaton MTL's industry-leading warranty
| Parameter | Value |
|---|---|
| Manufacturer | Eaton (Crouse-Hinds series MTL) |
| Series | TP48 Range |
| Configuration | 3-wire |
| Max. Working Voltage | 48V DC |
| Max. Surge Current (8/20 µs) | 20kA (peak) |
| Peak Voltage Rating | 10kV |
| Leakage Current | <10µA at max. working voltage |
| Bandwidth | 1MHz |
| Series Resistance | 0Ω — no resistance introduced into loop |
| Protection Technology | Hybrid — gas discharge tube + solid-state electronics |
| Enclosure Material | 316 Stainless Steel |
| Thread Type | 20mm ISO (M20 x 1.5) |
| Electrical Connections | Flying leads (4 leads: +ve, -ve, signal, earth) |
| Wire Size | 32/0.2 (1.0mm², 18 AWG) |
| Lead Length | 250mm (minimum) |
| Operating Temperature | -40°C to +85°C |
| Storage Temperature | -40°C to +85°C |
| Weight | Approx. 175g (6.2oz.) |
| Certifications | ATEX, IECEx, FM, CSA (hazardous area approved) |
The TP48-3-I-NDI is specifically designed to protect critical process instrumentation in demanding environments:
Suitable for protecting 3-wire transmitters measuring pressure, temperature, level, flow, and pH.
Unmatched Installation Simplicity — No electrician required for complex rewiring. Simply screw the TP48-3-I-NDI into the transmitter's unused conduit entry, and the protection is active.
Superior Protection vs. Built-in Options — Many transmitter manufacturers offer basic transient protection, but the TP48 series provides 20kA surge capacity — typically 10x higher than built-in options — at a fraction of the cost.
Certified for the Toughest Environments — The "NDI" certification ensures compliance with global hazardous area standards (ATEX, IECEx), allowing use in Zone 0, Zone 1, and Zone 2 classified areas.
Zero Signal Interference — The parallel connection design introduces no series resistance into the 4-20mA loop, preserving measurement accuracy and HART communication.
| Model | Wires | Thread | Certification | Best For |
|---|---|---|---|---|
| TP48-3-I-NDI | 3-wire | 20mm ISO | Certified (ATEX) | Hazardous areas, metric thread transmitters |
| TP48-3-N-NDI | 3-wire | 1/2" NPT | Certified (ATEX) | Hazardous areas, NPT thread transmitters |
| TP48-3-G-NDI | 3-wire | G 1/2" (BSP) | Certified (ATEX) | Hazardous areas, BSP thread transmitters |
| TP48-3-I | 3-wire | 20mm ISO | Non-certified | General purpose, metric thread |
| TP48-4-I-NDI | 4-wire | 20mm ISO | Certified (ATEX) | 4-wire transmitters in hazardous areas |
| TP48-I-NDI | 2-wire | 20mm ISO | Certified (ATEX) | 2-wire loop-powered transmitters |
| Item | Details |
|---|---|
| Part Number | TP48-3-I-NDI |
| Brand | Eaton Crouse-Hinds series MTL |
| Condition | New, Original, Factory Sealed |
| Minimum Order Quantity | 1 piece |
| Warranty | 10 Years (Eaton "No Fuss" Warranty) |
| Shipping | Immediate dispatch via DHL, FedEx, UPS, TNT |
Contact our sales team for volume pricing, datasheet downloads, or technical application support.
Suitable for use in SIL-rated loops per IEC 61508/61511
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