Intelligent building automation in offices and general commercial buildings can provide a more comfortable working environment for employees. In addition, room climate automation saves energy and reduces operation costs. But what happens when devices in the system cannot communicate with each other?
Forest Eco Systems Ltd. recently used a Contemporary Controls' BACnet/IP Client/Server to resolve a communication issue between devices in an office automation system. An automation control unit and a fan coil unit (FCU) operated as BACnet servers and hence could not read/write to each other. Contemporary Controls' BASC-22CR provided the communication bridge to synchronise operation of both devices.
Forest Eco systems was looking to read and write to/from a Siemens controller DXR2.E09-101A using a Loxone Miniserver in a control panel built by Zmart Hohm.
According to Zach Meek, renewables manager, Forest Eco Systems, "The Loxone Miniserver is an intelligent building automation tool which looks at a lot of variables to determine which rooms need heating and the most efficient way to heat them."
For example, the control unit uses motion sensors to determine which rooms are occupied and if they require heating. It detects if any windows or doors are open, and then tries to passively heat the room using solar gain — by raising or lowering the blinds — before activating the hybrid air source heat pump. It will also try to passively cool the rooms by lowering the blinds. The control unit also tracks the trajectory of the sun to optimally cool the space without obstructing the occupants' view.
"The unit was also programmed with a self-learning program, so it calculates if it's more cost effective to increase the fan speed or flow temperature, and it extracts data to monitor system performance," said Meek. "The problem we had was with the integration between the automation control unit and the FCU that operates using BACnet." The FCU delivered the points list — room temperature, cooling setpoint, maximum fan speed, etc. — but these values were not visible within the Loxone configuration software.
The BASC-22CR is a BACnet/IP server and also provides BACnet/IP client capability. This allows the user to read and/or write points served up by devices on the BACnet internetwork over Ethernet with the use of Network Variable (NetV) Sedona components. NetV components allow the BASC-22CR to read and/or write Analog Input (AI), Binary Input (BI), Analog Value (AV), Binary Value (BV), Analog Output (AO), and Binary Output (BO) BACnet object types in its wiresheet.
In this scenario, the BASC-22CR reads data from the Siemens FCU and submits (writes) it to the Loxone server. Then, the Loxone server makes the calculation, the BASC-22CR reads the Loxone points list and sends (writes) the values to the FCU.
"The BASC-22CR, plugged into a LAN port at the office site, provided the exact solution we needed," said Meek. "We can now read and write commands to and from both devices."
The BAScontrol22C is part of Contemporary Controls' line of the BAScontrol Series BACnet/IP Sedona Unitary Controllers. The BAScontrol22C is an BACnet/IP server and also provides BACnet/IP client capability which allows the user to read and/or write points served up by devices on the BACnet internetwork. It is a 22-point unitary controller that supports BACnet/IP and Sedona using Ethernet connections. The controller has a convenient mix of physical I/O points, including 8 universal inputs, 4 contact closure inputs, 4 analogue outputs, and 6 relay outputs. 48 web components and 24 virtual points are supported as well and are web-page configurable. Two 10/100 Mbps Ethernet ports supports BACnet/IP and other protocols.