Siemens 6ES7138-7BB00-0AB0 SIMATIC ET 200iSP Watchdog Module Ex ib IIC T4 Remote I/O Accessory

The Siemens 6ES7138-7BB00-0AB0 is a watchdog module for the SIMATIC ET 200iSP intrinsically safe I/O station, monitoring the connected digital output modules on the power bus and reporting a group fault through its red SF LED. It runs from a 20.4-28.8 V DC supply, mounts on rail, front, or wall, and is rated IP30 with Ex ib IIC T4 Gb / Ex ib I Mb approval for Zone 1 gas and Group I mining areas.

Technical Specifications

Certifications & Standards

• GL
• ABS
• BV
• DNV

Selection Notes

This module has no digital inputs or fieldbus interfaces of its own; its job is watchdog supervision of the ET 200iSP power bus, so it is needed only when the station includes digital output modules whose power-bus feed must be monitored for a stuck or failed watchdog cycle. Its Ex ib IIC T4 Gb / Ex ib I Mb rating covers both surface gas Zone 1 installations and underground Group I mining areas from the same catalog number. The four marine class approvals (GL, ABS, BV, DNV) make it usable on shipboard hazardous-area I/O stations without a separate maritime-rated variant.