Application guide for nVent TraceTek alarm modules using MTL-7767+ and MTL-7764+ zener safety barriers in hazardous areas.
This document provides application guidance for nVent RAYCHEM TraceTek alarm and locating modules, specifically regarding the use of zener safety barriers in hazardous locations. It details the requirement for MTL Incorporated barriers (MTL-7767+ and MTL-7764+) to ensure energy levels remain below explosive ignition limits when sensing cables are installed in Class I, Division 1 or Zone 0/1 areas. The guide includes catalog numbers for purchasing these barriers with TraceTek systems.
| Required for hazardous area sensing cables | Class I, Division 1 or Zone 0/1 locations |
|---|---|
| Number of barriers required per module | Two barriers |
| Catalog number for MTL-7767+ barriers | TT-ZENER-BARRIER-7767 |
| Catalog number for MTL-7764+ barriers | TT-ZENER-BARRIER-7764 |
| Additional leak location distance for MTL-7767+ | approximately 9 meters (30 feet) |
| Additional leak location distance for MTL-7764+ | approximately 80 meters (262 feet) |
A protective device such as a zener safety barrier is required when the sensing cable is installed in a hazardous area, particularly Class I, Division 1 or Zone 0/1 locations.
nVent has standardized on the MTL-7767+ and MTL-7764+ models manufactured by MTL Incorporated.
The MTL barriers will add resistance to each leg of the TraceTek sensor cable, impacting leak detection sensitivity when using TT1000, TT1100-OHP or TT3000 sensor cable.
No, avoid using MTL 7764+ barriers with TTSIM-1A or TTSIM-2 modules when the sensor cable is TT1000, TT1100-OHP or TT3000.