Specifications
Publication 1794-SG002D-EN-P - May 2012
72 About the FLEX Ex I/O Systems
Plug the I/O module into the terminal base. Use the module to connect to the
I/O bus and field devices.
Remove and insert modules under power. No direct wiring to the module
enables you to change modules without disturbing field wiring or system power.
Mix and match I/O modules. Wide variety of digital, analog, temperature,
frequency, and HART modules.
FlexBus Isolator allows connection to standard FLEX I/O adapters and I/O
thus providing a choice of other networks.
Conformal coating on all modules meets the noxious gas requirement of
ISAS71.04-1985 severity level G3 for hydrogen sulfide, sulfur dioxide, chlorine,
nitrogen dioxide, hydrogen fluoride, ammonia, and ozone.
FLEX Ex combines a terminal strip and intrinsic-safety isolation with an I/O
interface. Use the terminal strip on the terminal base to wire your field devices
directly. The FLEX Ex design also offers these features:
• modularity for distributed IS systems
• all of the features of a larger, rack-based system
• installation near the field devices to reduce wiring costs and complexity
• terminations for field wiring eliminating the need for marshalling or extra
terminal strips
• ControlNet-based networking solution in the hazardous area with
ControlNet Ex products
•DIN-rail mounting
FLEX Ex provides additional value if system problems develop. The terminal
base lets you remove and insert I/O modules under power without rewiring or
disrupting your system. Combining your field-wiring terminations, IS isolation,
and the I/O interface into the same location saves you time, money, and makes
your system easier to maintain and troubleshoot. Additional benefits include:
• galvanic isolation between the I/O backplane, input circuitry, and power
supply
• dual-fault protection IS circuits provide the highest fault tolerance
• I/O circuitry provides full IS field-device protection
• the modules themselves are IS protected for installation in hazardous
environments
FLEX Ex I/O modules may be removed and inserted while operating under
power. Network module maintenance and cable connections can be made in the
hazardous area while the system is in operation and the area is hazardous.