Siemens S54370-B7-A1 Test Switch Module

TSM-1X Intelligent Test Switch Module, P/N S54370-B7-A1, is an addressable, key-activated momentary switch (T-45) with a tri-color LED indicator designed for Siemens Desigo and Cerberus PRO fire alarm systems. The S54370-B7-A1 variant includes dual isolators to maintain loop integrity and isolate faults during testing. This normally open (NO) test switch sits on the Device Loop Circuit of Desigo FC2025/FC2050/FV2025/FV2050 and Cerberus PRO FC922/FC924/FV922/FV924 systems, enabling technicians to initiate tests of connected detectors and intelligent devices through the control network while remaining addressable within the system. The built-in tri-color LED provides visual status feedback during operation, and the device's addressability supports precise identification on the intelligent loop. In short, the TSM-1X S54370-B7-A1 offers a dedicated, configurable test point on advanced fire alarm networks, combining controlled test capability with loop fault tolerance inherent to its dual isolators.