Automation Of HVAC System with PLC

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• Automation Of HVAC System with PLC
• A Presentation

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A Generalized Manual Air-Conditioning System
A/Cs
A/Cs
AC Duct able
ROOM6
AC Duct able
ROOM1
AC Duct able
A/Cs
Splits A/Cs
ROOM7
AC Duct able
AC Duct able
A/Cs
ROOM4
ROOM2
AC Duct able
ROOM8
A/Cs
AC Duct able
A/Cs
AC Duct able
AC Duct able
A/Cs
ROOM9
ROOM5
ROOM3
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DRAWBACKS OF MANUAL AIR-CONDITIONING SYSTEM

• No centralized control of operation.
• Difficulty in troubleshooting in case of fault
  occurrence.
• No scheme for energy conservation.
• Panel locations are generally not organized.
• Most of the system operation is manual.
• No tripping alerts for power consumption
  triggered over maximum kva rating.
• No self regulation facilities.

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MODIFICATIONS IN MANUAL AIR-CONDITIONING SYSTEM

• Centralized control panel will communicate with
  existing remote panels.
• Graphical visualizations with real time data like
  status, set actual temperature, trends, alarms
  etc.
• Automatic system along with the manual override
  facility.
• Tripping alerts for power consumption triggered
  over maximum kva rating.
• Seasonal variations in control will be provided.
• Operators login tracking will be provided.

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BMS SOFTWARE
SENSORS
ROOM1
Energy Meter
ROOM2
ROOM3
ROOM4
MODBUS
ROOM5
ETHERNET / OPC
ROOM6
ROOM7
OUTPUT TO A/Cs
ROOM8
ROOM9
PLC
ROOM10
ROOM11
ROOM12
ROOM13
ROOM14
ROOM15
ROOM16
AREA TEMPERATURES
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CENTRAL CONTROL ROOM
BMS SOFTWARE
DUCT TYPE SENSORS
PLC
RETURN LINE
ROOM
A/Cs
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ROOMS with PLC BASED AC controls
PLC
AC Duct able ROOM2
AC Duct able ROOM3
AC Duct able ROOM1
AC Duct able ROOM5
AC Duct able ROOM6
AC Duct able ROOM4
AC Duct able ROOM8
AC Duct able ROOM9
AC Duct able ROOM7
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ENERGY CONSERVATION Through PLC Based Automation
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POWER CONSUMPTION PER HOUR
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POWER CONSUMPTION PER HOUR
TRIPPING IF CONSUMPTION GOES OVER DEFINED LEVEL.
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SEASONAL VARIATION IN CONTROL
Atmospheric temp. (Seasonal) 23
deg C
BMS Software
sensor
Room temperature 24 C
CONTROLLER
A/Cs
Sensed temperatures
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AUTOMATION PACKAGE

• Eight level password protection to avoid
  unauthorized access.
• Set actual temperature for different areas.
• Real-time historical trending for individual
  A/Cs
• Scheduling.

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AUTOMATION PACKAGE

• Process visualization
• Status of all units.
• Compressor status.
• Return air temperature status.
• Running hours for all ACs.
• Auto / manual selection.
• Alarm summary history.
• Real time clock.

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Advantages Of PLC Based Automation

• Optimum Start/Stop of A/Cs .
• Saving of Electricity.
• Anti-recycle timer.
• On Line Programming.
• Better Temperature Resolution.
• PLC Fault Diagnostic.
• Automatic restart.
• Temperature data scanning interval is 1 second.

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CUSTOMER BENEFITS

• Centralized control with maximum KVA demand being
  the primary parameter room temperature as
  secondary parameter or vice versa as required.
  (As the kVA demand approaches the set limit, the
  air conditioner compressors in room with
  temperatures nearer to the set temperature will
  be switched off.)
• Maximum Energy savings.
• Centralized control monitoring system.
• Easy control with complete information. Operator
  can better analyze the operation of their control
  area.

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CUSTOMER BENEFITS

• Easy fast control from control room as system
  uses ETHERNET / OPC / SNP as protocol.
• History for individual units like running hours,
  status, alarms, trends etc.
• Self regulation based on outer atmospheric
  temperature.
• Auto tripping alerts if load demand exceeds
  specified (KVA) ratings.
• Convenience of future expansion in proposed
  system.