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Enclosure requirements General requirements Megablocks may be mounted in hazardous (classified) areas – see section 8.  The following conditions must also be satisfied to ensure safe and reliable operation. a) Prevent any form of pollution that could compromise the operation of the unit. For example, choose an unpolluted location or a suitable enclosure to protect the assembly. b) Provide an adequate level of mechanical protection. This can be achieved by selecting a protected location, a suitable enclosure, or a combination of both. c) Ensure that all cable entries and connections are secure by making provision for the careful routing and securing of all cables. d) Provide adequate security against unauthorized interference. e) Conform to the permitted ambient temperature range of –45°C to +70°C. Outdoor mounting In addition to the General Requirements above, if the Megablock is mounted in an outdoor location, use a suitable enclosure with a minimum of IP54 ingress protection. A higher level of ingress protection rating will be necessary if the working atmosphere is, or can be, corrosive, or if the enclosure is subject to wet or dusty environments.

DESCRIPTION Simple and reliable interconnection Each Megablock has dedicated connections for the fieldbus “home run” or trunk cable. Trunk connections are identified by their black connectors. Numbered (grey) connectors are provided for each spur. Wiring connections to the Megablock are made using pluggable connectors (screw terminal type are standard, but other connection styles are available). These allow wire terminations to be made to the individual connectors, which are then plugged into the Megablock.  Devices can be connected and disconnected easily during commissioning. On completion, the connector retaining screws are tightened to secure each connector to the Megablock MECHANICAL Mounting orientation Megablocks mount vertically or horizontally on 35mm DIN rail within a field junction box  The use of DIN rail end stops are recommended to prevent sliding (especially for vertical installations). Eight, and twelve port Megablocks have areas on their body for labelling so that segments can be easily identified according to plant standards.

F300 Megablocks are DIN-rail mounted, device couplers for Foundation™ fieldbus

or Profibus PA networks. They allow connection of field devices to the segment

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.

Megablocks are available in four, eight, and twelve port versions. Multiple

Megablocks are easily wired together to allow larger segments to be constructed.

Each F300 Megablock includes an F97 Terminator for installation in the trunk

terminals, which is clearly marked with a large ‘T’ for easy identification by field

personnel.

Individual surge-protector modules (FS32) can also be fitted to any of the

Megablock fieldbus terminals to provide protection against induced surges and

transients that can potentially destroy or degrade certain components inside the

F300 Megablocks.

DIN-rail mounting The Megablocks are designed for mounting on 35mm x 7.5mm T-section “top hat” DIN rail to EN50022 and use built-in DIN rail clips to attach to the rail. Mounting procedure Megablocks are attached to the DIN rail using a “push-and-tilt” method – as illustrated on the body label and in Figure 4.1 below. Tilt the Megablock towards the trunk-connector side of the Megablock and then engage the DIN-rail clips under the ledge of the DIN rail. Push the Megablock against the edge of the rail then rotate the Megablock until it sits flat onto the DIN rail, then release the pressure to allow the clips on the other side to engage. Removal from DIN-rail Refering to Figure 4.1. push the Megablock against the edge of the DIN rail, tilt the other side of the Megablock up and away from the DIN rail, then release the side pressure to disengage the DIN rail clips from the DIN rail ledge.  

Enclosure requirements General requirements Megablocks may be mounted in hazardous (classified) areas – see sections 8 & 9. The following conditions must also be satisfied to ensure safe and reliable operation. a) Prevent any form of pollution that could compromise the operation of the unit. For example, choose an unpolluted location or a suitable enclosure to protect the assembly. b) Provide an adequate level of mechanical protection. This can be achieved by selecting a protected location, a suitable enclosure, or a combination of both. c) Ensure that all cable entries and connections are secure by making provision for the careful routing and securing of all cables. d) Provide adequate security against unauthorized interference. e) Conform to the permitted ambient temperature range of –50°C to +70°C. Outdoor mounting In addition to the General Requirements above, if the Megablock is mounted in an outdoor location, use a suitable enclosure with a minimum of IP54 ingress protection. A higher level of ingress protection rating will be necessary if the working atmosphere is, or can be, corrosive, or if the enclosure is subject to wet or dusty environments.

Simple and reliable interconnection Each Megablock has dedicated connections for the fieldbus “home run” or trunk cable. Trunk connections are identified by their black connector. Numbered (grey) connectors are provided for each spur. Wiring connections to the Megablock are made using pluggable connectors (screw terminal type are standard, but other connection styles are available). These allow wire terminations to be made to the individual connectors, which are then plugged into the Megablock.  Devices can be connected and disconnected easily during commissioning. On completion, the connector retaining screws are tightened to secure each connector to the Megablock. MECHANICAL Mounting orientation Megablocks mount vertically or horizontally on 35mm DIN rail within a field junction box.  The use of DIN rail end stops are recommended to prevent sliding (especially for vertical installations). Eight, and twelve port Megablocks have areas on their body for labelling so that segments can be easily identified according to plant standards.

OVERVIEW F200-IS Megablocks are DIN-rail mounted, device couplers for FOUNDATION™ fieldbus or Profibus PA networks. They allow connection of field devices to the segment 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. Megablocks are available in four, eight, and twelve port versions. Multiple Megablocks are easily wired together to allow larger segments to be constructed. Individual surge-protector modules (FS32) can also be fitted to any of the Megablock fieldbus terminals to provide protection against induced surges and transients that can potentially destroy or degrade certain components inside the F200-IS Megablocks. Removal from DIN-rail Refering to Figure 4.1. push the Megablock against the edge of the DIN rail, tilt the other side of the Megablock up and away from the DIN rail, then release the side pressure to disengage the DIN rail clips from the DIN rail ledge.

F300 Megablock hazardous area approvals permit

installation in a variety of configurations in Zone 2 and Division 2

hazardous areas. Typically, F300 Megablocks may be installed with

non-sparking (non-arcing) trunk and spur connections. Alternatively,

when connected to suitably certified fieldbus power supplies, the trunk

may be non-sparking (non-arcing) with non-incendive or intrinsically

safe Ex ic spur connections.

When installed on a non-sparking trunk with Ex ic spurs, an

F300-A01 trunk-spur partition must be installed on the F300 Megablock.

The trunk-spur partition is supplied as a pack of 5. as detailed in the

Accessories section of this document.

SpurGuard™ is a device-port, short circuit protection technique

that minimizes susceptibility to single points of failure. The F300

Megablock has built-in SpurGuard™ protectors that prevent a short

circuit in any of the individual field devices or spur cable runs, from

bringing down the entire fieldbus segment. A red LED near each

spur connection indicates when a spur is shorted and hence in “over

current” mode.

The optional FS32 modules can provide surge protection for the

F300 products on both the trunk and spur terminals. These pluggable

modules are simple to fit in a new installation, or as a retrofit option.

A range of MTL Process Junction Boxes in stainless steel and carbon

loaded, glass-reinforced polyester are available for mounting Megablock

wiring components. They offer plenty of space for termination and

wiring, making it easy to install and maintain the fieldbus system.