Passive Hubs for Zone 1 Fieldbus Networks

Megablocks are DIN-rail mounted passive hubs for Foundation™

fieldbus networks. They connect several field devices to the network

trunk cable and provide short circuit protection to the segment.

Megablocks minimize hand wiring and allow individual devices to be

added to and removed from the segment without disrupting network

communication.

A green power LED on each unit indicates whether at least 9V dc

is present. F2xx-XE Megablocks are available in four, eight, ten and

twelve drop versions. Multiple Megablocks are easily wired to one

another to allow larger segments to be constructed.

Megablocks are available with an integral terminator making

them ideal for a star or “chickenfoot” topology where several devices

are connected at a single field junction box. Separate Megablock

Terminators are also available, whch may be wired easily to any

Megablock. Megablocks having a built-in terminator are clearly

marked (‘T’) for easy identification by field personnel.

Connections to the Megablock are made using pluggable, screw

terminal type connectors. This allows wire terminations to be

made to the individual connectors which are then plugged into the

Megablock. Devices can then be connected and disconnected easily

during commissioning. After commissioning, retaining screws are

tightened to secure each connector to the Megablock.

Trunk connections for the fieldbus home-run/ trunk cable are easily

identified by their black connectors. Separate numbered connections

are provided for each spur drop.