XTRI-R incorporates ISO technology the configurable, built-in
dual isolator function. Additionally, an XTRI series interface module supports NFPA
72 Class X (Style 7) survivability requirements for shorts while providing reliable
alarm communication to the Siemens FACP. The isolation feature found on the
XTRI series Intelligent Interface Modules gives information as to the location of the
fault. When a short occurs, the panel can identify the fault automatically, and the
module recognizes the short location (in front of the device or behind the device).
Overall, the built-in isolators improve the diagnostics and location of the problem,
including a short.
The modules are configurable by a Siemens compatible FACP (or panels) in an
isolator (polarity sensitive) or non isolator (polarity insensitive) mode. When a
XTRI series interface module is configured as an isolator, that module has the
capacity of functioning as both an in/out device, as well as an isolator.

Through the use of an addressable ‘Form C’ relay, the Model
XTRI R relay and contact device input are controlled at the
same address. The relay and input contact can be controlled
as a separate function from a Siemens-compatible FACP. The
relay is typically used where control or shunting of external
equipment is required.