Distech ECYPSE - ECB-PTU Line-Powered Data Bus Controller Shield Grounding Requirements

BACnet MS/TP Communication Data Bus Fundamentals
120 ECLYPSE User Guide
Typical BACnet 24VAC-
Powered Controller
Data Bus Shield:
Isolate with
electrical tape
Data Bus Shields: Twist
together and Isolate
with electrical tape
Typical BACnet 24VAC-
Powered Controller
Typical BACnet 24VAC-
Powered Controller
Data Bus: Shielded Twisted Pair Cable
NET+ NET- NET+ NET- NET+ NET-
Typical BACnet 24VAC-
Powered Controller
NET+ NET-
Data Bus Shield:
Isolate with
electrical tape
Data Bus Shields:
Connect to the ‘S’
terminal
Electrical
System
Ground
The shield of the data bus must be connected to
the electrical system ground at one point only –
usually at the Building Controller, when present
Data Bus Shields: Twist
together and Isolate
with electrical tape
ECY Series
NET- NET + S
Figure 11-7: Typical Cable-Shield Grounding Requirements for a BACnet MS/TP
Data Bus Segment with an ECY Series Controller located in the Middle of the Data
Bus
ECB-PTU Line-Powered Data Bus Controller Shield
Grounding Requirements
The shield on each data bus segment must be connected to the electrical system ground at
one point only, for example, at the ECY Series Controller, as shown below in Figure 11-8
and Figure 11-9.
Data Bus: Shielded Twisted Pair Cable
Typical BACnet Line-
Powered Controller
Data Bus Shields: Twist
Together and Connect
to ‘COM’ Terminal
NET- NET+ COM
Typical BACnet Line-
Powered Controller
Data Bus Shields: Twist
Together and Connect
to ‘COM’ Terminal
NET- NET+ COM
Typical BACnet Line-
Powered Controller
Data Bus Shields: Twist
Together and Connect
to ‘COM’ Terminal
NET- NET+ COM
Typical BACnet Line-
Powered Controller
Data Bus Shield:
Connect to ‘COM’
Terminal
NET- NET+ COM
Data Bus
Shield:
Connect to
the ‘S’
terminal
ECY Series
NET- NET + S
Electrical
System
Ground
The shield of the data bus must be connected to
the electrical system ground at one point only –
usually at the Building Controller, when present
Figure 11-8: Typical Cable-Shield Grounding Requirements for a BACnet MS/TP
Data Bus Segment with an ECY Series Controller located in the End of the Data
Bus
ECY Series
NET- NET + S
Data Bus: Shielded Twisted Pair Cable
Data Bus
Shields:
Connect to
the ‘S’
terminal
Typical BACnet Line-
Powered Controller
Data Bus Shields: Twist
Together and Connect
to ‘COM’ Terminal
NET- NET+ COM
Typical BACnet Line-
Powered Controller
Data Bus Shield:
Connect to ‘COM’
Terminal
NET- NET+ COM
Typical BACnet Line-
Powered Controller
Data Bus Shield:
Connect to ‘COM’
Terminal
NET- NET+ COM
Typical BACnet Line-
Powered Controller
Data Bus Shields: Twist
Together and Connect
to ‘COM’ Terminal
NET- NET+ COM
Electrical
System
Ground
The shield of the data bus must be connected to
the electrical system ground at one point only –
usually at the Building Controller, when present
Figure 11-9: Typical Cable-Shield Grounding Requirements for a BACnet MS/TP
Data Bus Segment with an ECY Series Controller located in the Middle of the Data
Bus