DeviceNet products - Molex - #2

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9 DeviceNet™ Connections from the trunk line to the active nodes are generally made via a 5-pole Mini-Change® connection using “thick” cable (mid cable can also be used). Both ends of the trunk line MUST be terminated with 121 ohm resistors. Thin Media Drops are branches off the trunk and generally use “thin” cable up to 6m (20ft) in length. “Mid” cable can also be used for longer drop lengths or to standardize with “mid” trunk cable. Power Media I/O modules with output connections require 24V DC auxiliary power which is fed through the block via a 4-pole Mini-Change® connection. For safety reasons, the auxiliary power is brought to the block using a female connector so as to never have “live” power available on exposed pins. In some cases, machine stop circuits are run through the same 4-pole connectors. Machine stop drop or power tees, as well as termination plugs, are generally colored red for fast identification. Cordsets Input and output connections from the passive boxes or active I/O modules to devices like sensors or valves are made with industry standard 12mm DC style connections. I/O Connections I/O connections can be made to the network via 1) Mini-Change® connections, 2) Micro-Change® connections or 3) Open style 1.5mm spacing 5-pole industrial rated ODVA-approved connections. Active I/O Devices These are otherwise called “smart”I/O devices which can be directly connected as nodes onto the DeviceNet network. Detailed information can be received back from the “smart” I/O devices, such as a sensor being able to report back such information as distance measurements, power status, lasttime to maintenance, etc. Active I/O Modules Active Modules serve to interconnect a variety of I/O devices as a DeviceNet “node.” This allows the use of less costly standard sensors or outputs which are available from a variety of manufacturers and connect them onto the network providing short circuit protection while not disrupting DeviceNet communications. There are a variety of LED status indicators on DeviceNet active modules, including active, not active, and fault condition of input and output circuits and power status. Media DeviceNet uses a trunk and drop connection topology. The trunk is the main communications cable; the maximum length is dependent upon the communication rate and cable type used (thick, mid or thin). Drop connections are used to connect active nodes to the trunk. In all cases, DeviceNet cable consists of a shielded twisted pair and an independently shielded twisted power pair for the 24V DC bus power. These independently shielded pairs are then encased in an additional outer shield and jacket. Thick Media DeviceNet cable consists of a shielded twisted data pair and an independently shielded twisted power pair for the 24V DC bus power. These independently shielded pairs are then encased in an additional outer shield. Bus Drop Tee Pages 30-31 Trunk Passive Boxes Pages 36-37 Trunk Single-Ended Cordsets Pages 22-23 Active I/O Modules Pages 12-15 Sensor Cordsets See Brad Harrison® Designer’s Guide Drop Single-Ended Cordsets Pages 46-47 Trunk Termination Resistors Pages 40-41 Human Machine Interface Drop Receptacles Pages 58-59 Drop Double-Ended Cordsets Pages 48-51 Bus Extender Pages 16-17 Active I/O modules Pages 12-15 Open Drop Connectors Pages 56-57 Trunk-Field-Attachable Connectors Pages 42-43 For product & technical information visit www.woodhead.com/eCatalog