2-Wire Subnetwork Data Bus - Distech Controls ECL/ECB-PTU Series User Manual

2-Wire Subnetwork Data Bus

The 2-Wire subnetwork data bus is used to connect ECx-4XX Series I/O Extension Modules to
an ECB-600 or ECL-600 controller. The specifications for this cable are shown in
2-Wire Subnetwork Data Bus is Polarity Sensitive
The polarity of the 2-wire subnetwork data bus must be respected as shown in
terminals identified as SUBNET+ must be connected to the same conductor. Likewise, all ter-
minals identified as SUBNET- must be connected to the same conductor.
2-Wire Subnetwork Data Bus Physical Specifications and Cable Requirements
Cables composed of stranded conductors are preferred over solid conductors as stranded
conductor cable better resist breakage during pulling operations. Distech Controls strongly
recommends the following 2-wire subnetwork data bus cable specifications be respected.
Table 23: Cat 5e Cable Subnetwork Data Bus Physical Specifications and Cable Requirements
Parameter
Maximum number of ECx-4XX Series I/O
Extension Modules
Subnet ID Addressing Configuration
Media
Characteristic impedance
Distributed capacitance
Maximum total length of the Cat 5e Cable
subnetwork data bus plus the 2-wire subnet-
work data bus
Polarity
Multi-drop
EOL terminations
Shield grounding
92
Details
2
DIP switch located on faceplate.
O Extension Module Addressing
95.
Shielded, twisted pair
100-130 Ohms
Less than 100 pF per meter (30 pF per foot)
300 m (1 000 ft.) Maximum – See
work Data Bus Length on page 75.
Polarity sensitive
Daisy-chain (no T-connections, no routers)
Built-in. Must be set / enabled on the last
ECx-4XX Series I/O Extension Module only.
See 2-Wire Subnetwork Data Bus Shield
Grounding Requirements
Table 23.
Figure 62. All
ECx-4XX I/
on page
Subnet-
on page 94.
Network Guide