System Requirements To Install A Intelligent Building Management System To A Building

This article is about the installation of intelligent building management system to a high rise building.
When we consider about to install a Intelligent building management system to a high rise building, first of all we should consider the existing facilities of the selected building. It is important to identify monitoring and controlling requirement of building servicers through BMS.
Systems proposed to integrate with BMS
• HVAC
• Electrical distribution
• Lighting
• Fire detection and protection system
• Access control and CCTV system
• Water management system

Following include comprehensive description of systems proposed to integrate with BMS.

HVAC SYSTEM
HVAC (Heat Ventilation & Air Conditioning) is significant component when consider any facility. Cost derive from the system is large amount in the final output and controlling it is important to optimum building operations and the reduce operation cost. HVAC system is the most salient feature in the considered building automation system. Necessity of the integration HVAC system with building automation system can be identified as follows


• Energy Conservation Tool
Along with good building design and efficient HVAC plant, the BMS plays a vital role in the prevention of energy waste and reducing the environmental impact of the building. Actually when analyzing immediate information regarding operations of a high rise building, around 40% - 60 % of the electricity consumption derive from the HVAC system. Therefore if integrate a HVAC System with BMS that will highly impact on the energy conservation.

• Automatic ON/OFF switching of plant

The practical problem in most of the office building is the large number of complaints from the tenants about the uncomfortable ventilation in the office areas. The main reason for that is informal ventilation control from the tenants. But automatic ON/OFF switching of plant can be based on time, type of the day and/or environmental conditions. It will help to avoid that inconvenience.

Currently available energy saving methods regarding HVAC
 Using By-pass valve
This valve system has been installed in the chiller. If returned chill water has low temperature (if there is no need to transfer condenser and cooling tower) then transfer to the evaporator through the by pas valve. As a result of this compressor doesn’t gain higher load.

 Insulation system
When chill water transfer through pipes to AHUs. If pipes do not insulate cooling capacity of chill water will reduce. Therefore to retain the cooling condition of the chill water, pipes must insulate well. In this building currently using insulation material is ‘thermplex’.

Identified sub systems, controlling and monitoring aspects in each sub system

1. Controlling sub system
• Water cooled chillers- 4 (Capacity 259 tons)
• Screw type compressors
• Box type cooling towers
• Air cooled packaged chillers.- 4(Capacity 7.5 tons)
• Air Handling Units
2. Monitoring sub systems

• Fans

This is a constant speed exhaust fan, which is normally controlled by means of a time schedule. The status of exhaust air fan is monitored and an alarm is generated whenever the exhaust air fan fails to respond to start-stop commands.

• Packaged units
a. Power supply failure
b. Room temperature
• Packaged chillers
• Split A/C units
• Window A/C units
• Close control A/C system

According to the above scenario it is easy to identify there is a reason for that classification based on how to impact to the operations in the facility.

Identified field devices (Sub systems) need to be integrated with system

Field devices (sensors, actuators, valves, etc.) play a vital role in the BMS operation. Functions of a field device are receiving signals and respond to the system. Basically field devices are can be considered as hands of the BMS. Following field devices are can be applied in BMS of the building.


Chiller Plant

 Water Temperature Sensor and Pressure transmitters
 Power supply for pressure transmitter
 Butterfly valve on/off
 Valve Actuator with feedback potentiometer
 Transformer for actuator
 Motorized Valves
 Water flow switch
 Current transducer
 Voltage transducer
 Power factor transducer
 Electromagnetic flow mete
Package Units
 Temperature Transducers

Air Handling Units (CAV)

 Temperature sensor
 Temperature Transducer
 Motorized Valves
 Valve Actuator with feedback potentiometer
 Transformer for actuator
 Damper Actuator
 CO2 sensor


Air Handling Units (VAV)

 Temperature sensor
 Temperature Transducer
 Pressure transducer
 Power Supply for Pressure transducer
 Motorized Valves
 Valve Actuator with feedback potentiometer
 Transformer for actuator
 Damper Actuator
 CO2 sensor


How to apply protocols for each sub systems

 Temperature sensors
 Motorized valve feedback Control room temperature
 Co2 sensor
 Flow meter
 Motorized valve Actuator controller
 VSD controller Control the devices
 Cooling tower fan
 AHU On/Off status
 Equipment power/failure status power supply failure supervision
 Equipment auto/manual status
 Cooling tower motorized valve
 Equipment on/off control Regulate air flow


Protocol application and Proposed System integration

M- Manufacture produced protocol

There are four chillers in the basement. These four chillers have connected each other serially and have integrated to the third party system. These chiller set cannot connect directly to the system because of chiller manufacture produced protocol cannot identify to the system. Manufacture produced device communicates with chiller set interface and send data to the converter which convert chiller manufacture produced RS 232 protocol into RS 485 protocol. The open link controller provides a cost effective method of enhancing customer utility of existing building management system. It is an application level integrator which facilitates interfacing third party HVAC controller networks.

Read More

1. What is Intelligent Building Management System
   
2. System Requirements to Install Intelligent Building System
3. Electrical Distribution System in the Intelligent Building System
4. Integration of Intelligent Building Management System With Vertical Transportation System
5. Integration of Lighting System to Intelligent Building Management System
6. Fire Detection and Protection System
7. Access Controller and Intruder Alarm System
8. Water Management System
9. Central Air Conditioning System