Bms Communications - Black Box CRCW-12 User Manual

Chapter 4: E2 Controller
To determine which sensors are enabled and operable for each unit, simply determine which index numbers, derived from the key
above, will produce the number shown in the screen.
In the example shown, the number for the lead unit is 15. This results from adding 1 Supply Temperature + 2 Return Humidity +
4 Remote Supply Temperature + 8 Remote Supply Humidity together, confirming those sensors are operable.
The number shown for Unit 2 is three, the result of adding 1 + 2. This confirms that Unit 2's supply temperature and return
humidity sensors are detected by the lead controller. If a one appeared instead for Unit 2, it would indicate the signal for the
return humidity sensor is not present. That sensor is either not enabled or it has failed.

4.7 BMS Communications

When BMS communications are used, the controller must be equipped with an optional expansion card designed for one of a
variety of serial communications protocols available (see Section 4.1.4). A communications port on the expansion card allows the
controller to be fields connected to a central Building Management System (BMS) for monitoring and control of data points.
An RS-485 serial port is available for Modbus or BACnet MS/TP protocols, and a 10BASE-T port is available for TCP/IP based
protocols such as BACnet over IP, BACnet over Ethernet, SNMP, or HTTP.
Page 96
Table 4-25. BMS communications parameters.
Supported Protocols
BACnet over IP
BACnet over Ethernet
HTTP
SNMP V1, V2c
Modbus over IP
BACnet MS/TP
Modbus RTU
Figure 4-97. Direct connection vs. daisychain connection.
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Media Connection
10BASE-T RJ-45 direct
RJ-45 direct
10BASE-T
RJ-45 direct
10BASE-T
RJ-45 direct
10BASE-T
RJ-45 direct
10BASE-T
Twisted pair Daisychain
Daisychain
Twisted pair