The TP48 surge protection device safeguards field-mounted process transmitters where it matters, right at the unit. After a simple installation (the TP48 screws into an unused conduit entry, with no additional modification)

Overview

The MTL TP48 series safeguards field-mounted process transmitters against induced surges and transients right at the source. Compact and self-resetting, each unit screws directly into a spare conduit entry—no loop wiring changes, conduit modifications or additional hardware required. Available in 2-, 3- and 4-wire versions, TP48 offers intrinsically safe (Ex ia) and flameproof (Ex d) approvals for hazardous-area installations.

Key Features

• Protects 2-, 3- and 4-wire transmitters without adding series resistance
• Direct conduit-entry mounting: ½″ NPT, M20 × 1.5 ISO or G ½″ BSP
• Hybrid protection: gas-filled discharge tube + solid-state electronics
• Surge capacity: 20 kA peak (8/20 µs)
• Leakage current < 10 µA
• Bandwidth 1 MHz—no signal attenuation
• 316 stainless-steel housing for harsh environments
• Automatic self-reset after each surge event
• Certified Ex ia IIC T4/T5/T6 Ga and Ex d IIC T4/T6 Gb (ATEX, IECEx)
• FM, CSA, UL approvals for global use
• 10-year “no-fuss” Eaton warranty

Technical Specifications

Parameter	Value
Maximum surge current	20 kA (8/20 µs)
Maximum working voltage (Un)	35 V dc
Leakage current	< 10 µA
Bandwidth	1 MHz
Response time	Instantaneous
Housing material	316 stainless steel
Conduit entries	½″ NPT, M20 × 1.5 ISO, G ½″ BSP
Flying leads	3-wire (line1, line2, earth)
4-wire (+ve, –ve, signal, earth)
5-wire (+ve, –ve, signal+ve, signal–ve, earth)
Wire size & length	1 mm² (18 AWG), 250 mm min.
Ambient temperature (operating)	–40 °C to +85 °C
Protection rating	IP66
Certifications	ATEX Ex ia/Ex d, IECEx, FM, CSA, UL
Warranty	10 years

APPLications

• Field-mounted 4–20 mA loops, RTDs and mV sources
• RS 232/422/485, Profibus, Modbus and Fieldbus networks
• Industrial Ethernet, HART and SCADA systems
• Oil & gas, chemical, pharmaceutical

About Eaton MTL Instruments

Eaton MTL Instruments, a division of Eaton Corporation (USA), is a global leader in surge protection solutions for signal, data and power applications. With over 50 years of experience, MTL products are engineered to perform reliably in harsh and hazardous environments.

Viet Thang Loi Technology Company Limited is the authorized distributor of Eaton MTL Instruments (MTL) and Eaton Crouse-Hinds (CEAG) in Vietnam. Please contact us for more details.