Building Management Systems (BMS) –– The Basics Explained
Contents
What is a BMS
BMS suppliers and integrators
Typical user interface options
BMS Simple User Interfaces – Built in
Display
BMS Simple User Interfaces – WEB Server
What does a BMS do?
The Day to Day Role of the BMS
Building Control Applications
Measuring and Monitoring Building
Performance
Benefits of having a BMS?
Advantages of BMS vs Stand Alone Control
Improved tenant comfort conditions
Energy Management and Reduce Operational
Costs
Management of Building Ratings - NABERS
Operational Considerations
Control Loop Tuning
Importance of System Documentation
System Maintenance
BMS Lifecycle Considerations
BMS The Basics Explained – Recap
What is a BMS
- Industry
jargon, terminology and acronyms
- What is a
building management and controls system
- BMS
suppliers and integrators
- Typical
system components
- Typical
user interface options
- Building Management Systems (BMS) also known as Building Automation Systems (BAS),
- Building Management and Control System (BMCS), Direct Digital Controls
(DDC) and Building Controls
- Other
terms associated with Control Systems include:
- Supervisory,
Control and Data Acquisition (SCADA)
- Programmable
Logic Controllers (PLC)
- Energy
Management System (EMS)
- Data
gathering panels (DGP)
- Modbus,
Lonworks, and Bacnet – All refer to communications protocols
- ‘ Front End’ – legacy term used to
refer to the BMS Operator Workstation
- Most
Common Current industry term –
- Building
Management System (BMS) or
- Building
Management and Control Systems (BMCS)
What is a BMS
• BMS systems are “Intelligent” microprocessor
based controller networks installed to
monitor and control a buildings
technical systems and services such as air
conditioning, ventilation, lighting
and hydraulics.
• More specifically they link the functionality
of individual pieces of building equipment
so that they operate as one complete
integrated system.
• Now installed in every major building or
facility with the availability of direct
integration
into all other building services such as security, access control,
CCTV, fire, Lifts and other
life and safety systems.
• Current generation BMS systems are now based on
open communications protocols and
are WEB enabled allowing integration of
systems from multiple system vendors and access
from anywhere in the world.
BMS suppliers and integrators
• Procured as a complete system that includes,
engineering, supply, installation,
programming and commissioning.
• Specialist Integrators that are either
directly associated with the
manufacturer or are
approved re-sellers.
• All Integrators should have full factory
technical support
• Need to work closely with Mechanical Services,
Mechanical Electrical and other
contractors.
• For new construction BMS is usually included
within the mechanical services
package.
• ‘Tier 1 Company’ only refers to a direct
factory association and not to the
quality of products or services…
Typical user interface options
Ø Can be a basic LCD display
through to full Graphic Operator Workstations.
Ø The Graphic Interface must
be intuitive to use and not require an Engineering degree to interpret
Ø They must provide sufficient level of detail to
enable the operator to determine what is happening and what is going to happen
next
Ø Graphics need to provide
access to parameters for tuning and seasonal information
needs to be built into
the system
BMS Simple User Interfaces – Built in Display
• User defined menus.
• Built into the BMS
controller or a remote device
• Password protected
• Monitor and control field
points, operating setpoints, time schedules, alarm management,
even trend data
BMS Simple User Interfaces – WEB Server
• WEB Server built into a
BMS network controller
• User defined menus and
graphic pages
• Password protected, multiple access levels
• Monitor and control field
points, operating setpoints, time schedules, alarm management,
even trend data
What does a BMS do?
Ø The role of the BMS in day to day building
operation
Ø Building Control Applications
Ø Measuring and Monitoring building performance
Ø Interaction with other building systems
The Day to Day Role of the BMS
• The most common primary function of the BMS is
the control of a buildings Heating, Ventilation and Air Conditioning Systems
(HVAC) including;
• Air Handling Units
• Chilled Water Plant
• Cooling Towers
• Tenant Condenser Water
• Heating Water Plant
• Exhaust Systems
• Zone Controls
• Computer Room AC
• WEB Server built into a
BMS network controller
• Control of Building Systems and Services
• Graphic User Interface (GUI)
• Real Time Monitoring of Building Operation and
Performance
• Trending and Logging of Building Operation and
Performance
• Time Scheduling of Building Systems
• Fault Management and Alarming
• Control Application Programming
• User Event Management
• Energy Management and Reporting (NABERS)
Building Control Applications
• Building control applications include for
following:
• Zone temperature monitoring and control
• Zone Variable Air Volume (VAV) control to zones
• Zone CO2 monitoring and control (Air Quality)
• Air handling unit supply air temperature
control
• Air handling unit supply air flow / pressure
control
• Main Plant Chiller and Boiler sequencing
• Toilet, car park, kitchen and general exhaust
fan control
• After Hours Building Control
Measuring and Monitoring Building Performance
• Operator Interfaces
including Graphical User Interface (GUI) for monitoring and
adjustments
• Trend data is important
when determining the stability of control algorithms and
when tuning the
system.
• Reports are pivotal when
demonstrating building performance against sustainability
targets such as
NABERS.
• Equipment alarm and fault
notification, reduces down time and consequential
impacts
Benefits of having a BMS?
Ø The advantages of a BMS versus stand-alone
control
Ø Improved Tenant comfort conditions
Ø Energy Management and reduced operational costs
Ø Management of building ratings such as NABERS
Advantages of BMS vs Stand Alone Control
• Reduced installation costs
• Flexibility and ease of change
• Customised control strategies
• Scalability
• Operator interaction, feedback and control
• Integration with other building services
Improved tenant comfort conditions
• Real time monitoring of tenant conditions
• Greater load based control strategies
• Trend data of performance, improved fault
finding
• Air quality management (CO2)
• After hours operational requests, tenant
billing
• Alarm notifications of faults reduce downtime
• Automated change-over of failed equipment
Energy Management and Reduce Operational Costs
• Optimal start and stop of plant
• Building warm up and cool down cycles
• Night purge
• Automatic Seasonal plant sequence selection
• Seasonal temperature setting adjustments
• Load based control strategies
• Economy cycle control including CO2
• Equipment runtime monitoring and duty cycling
• Occupancy control and control setback
Management of Building Ratings - NABERS
• Can be integrated with Energy Management System
(EMS)
• Real time monitoring of energy performance
• Proactive adjustment not retrospective catch up
• Measurement against load profile targets
• Separation of tenant and base building loads
• Historical trend data for NABERS management
• Energy demand and consumption dashboards
• EMS is a dedicated software packed for the
monitoring and management of electrical,
water, gas and thermal energy metering
systems.
Operational Considerations
• Tuning and optimisation
• Importance of System Documentation
• System Maintenance, what, how often and by whom
• Life cycle expectations and considerations
Control Loop Tuning
• BMS Tuning and Optimisation are not the same
thing.
• BMS Tuning or control loop tuning ensures that
the equipment operates in a stable, predictable and repeatable manner.
• Optimisation focuses on operating the equipment
in the most energy efficient manner
without impacting on the controlled
variable
• The first stage of optimisation includes BMS
loop tuning.
Importance of System Documentation
• Functional Description (FD)
•
Details
the configuration of the BMS
•
Overview
of the building services
•
Describes
in detail each of the BMS control strategies and sequences
of operation
•
Documents
interaction between each part of the system
•
Point
Schedules
•
Detail all
connected devices and their point type
•
Critical
for planning and system engineering
•
Control
System Drawings
•
Should
include a network architecture drawing
•
Detail the
physical wiring connections to controllers
•
Useful for
fault finding and establishing spare capacity
System Maintenance
• The BMS belongs to the building owner who
should act as its administrator
managing BMS access rights
• The BMS should be maintained with an
appropriate level of servicing
• As with any software driven system, data and
files should be backed up on a
regular basis
• Critical components should be identified and
checked at regular intervals
• BMS functions such as trend data, reports and alarms can be used to perform
maintenance
by exception
• Maintenance should be approached as the
performance of the controlled system
not individual components, i.e. AHU or
Chiller Plant
• While the BMS equipment vendor should be
utilised to maintain the critical
components, other suitably qualified technicians
can be utilised for field equipment
BMS Lifecycle Considerations
• Considerations:
•
Check
equipment production cycle status
•
Select
hardware with proven record (avoid beta)
•
Check for
level of software and hardware support
•
Check for
forward compatibility policy
•
Equipment
Lifecycle:
•
BMS field
controllers – 15 to 20 years
•
Field
devices – 15 to 20 years
•
BMS
computer hardware – 3 to 5 years
•
BMS
software – Major releases 3 to 5 years
BMS The Basics Explained – Recap
• BMS systems are “Intelligent” microprocessor
based controller networks installed
to monitor and control a buildings
technical systems and services such as air
conditioning, ventilation, lighting
and hydraulics.
• Scalable from just one device to thousands of
devices
• Link the functionality of individual pieces of
building equipment so that they
operate as one complete integrated system.
• Provide the building owners and operators with
the tools to manage the
performance and energy efficiency of their buildings
• Can be integrated into all other building
services such as security, access
control, CCTV, fire, Lifts and other life and
safety systems.
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