289761-01  ADAPT (ESD) Emergency Shutdown Device

The 3701/55 Emergency Shutdown Device, (ADAPT ESD) is a safety PLC with a graphical logic programming interface and
integrated overspeed detection. ADAPT ESD is designed for emergency shutdown of rotating machinery such as steam,
gas, and hydro turbines, expanders, and other process equipment.
ADAPT ESD is a compact, standalone, triple-redundant, safety shutdown device that is designed to meet a broad range of
user scenarios and applications. The design offers an electrical and mechanical package with attention to
reliability and availability as well as extensive self-diagnostics and compliance to industry standards.

370140 177896-05

Inputs
Inputs to the system are processed using three CPU modules to provide triple modular redundancy (TMR). Each CPU
processing module processes two unique speed input channels, for a total of six speed channels for the system. The
processing modules also monitor an array of 32 discrete (DI) and process variable (PV) signal inputs. Twelve channels of
this input signal array may be configured either as discrete inputs or 4-20 mA analog inputs. Remaining channels in the
array are reserved for discrete input signals only.
Outputs
Machinery shutdown functionality of the 3701/55 ADAPT ESD system is actuated by TMR relay output modules. Each relay
output module has five relays with a level of configurability that accommodates a variety of applications and
requirements. Four of the five relays in each module are used to annunciate system logic. The remaining relay reflects the
OK/NOTOK status of the associated protection path.