Environment Control Systems in Metro Project

1. Environmental Control System
(ECS)

2. Basic function of ECS
• Building’s environmental control
• Monitors and controls the operation of
associated VAC equipment
• In Metro project, ECS is generally controlling
and monitoring other E&M and building
systems as well

3. Basic Control System concept

4. Main objectives
 Efficient Operation
-Remote ON/OFF commands, manual or auto operation
-Change of set points from remote central control
-Software safety interlocks for safe operation of systems
-Automatic change over i.e duty/ standby on run hours basis
-Mode selection: programmed normal & maintenance modes
-Emergency response: Emergency modes
 Maintenance Management
-Alarm/alert in case of equipment /device failure
-Maintenance alerts on accumulated run hours
-Data logging and trending

5.  Cost saving throughout the life of the systems
-Eliminating human operators in each station
-In cooler season 100% outside air is used by mode selection
-Systems do not run when not needed
-Staggered start/ stop functions to limit stresses and losses
-Use of Lighting Management System for public areas
 Interface with other building systems
 Facilitates centralized/remote control and monitoring

6. ECS as applied to Metro Project
 Design Requirements
- Typical design parameters
- Control and monitoring functions
- Interface functions
 Scope of Works
- Summary of Stations & other Metro buildings
- List of Systems covered
- Quantities of Major Equipments
 Technical Solution

7. Typical design parameters
Station Areas Design Temperature ο C Design Humidity %RH
Concourse 26 35-55
Platform 26 35-55
BOH staff rooms 24 35-55
SMO 24 55+/-10
Entrances 28 35-55
Equipment rooms Max 40/45 Uncontrolled or ≤ 85
Signal/COM room 24 Uncontrolled

8. Interface functions
 OCS
- Time table control
- Temperature and Humidity set points
- Equipment Control and Monitoring
- Normal and Emergency mode Control and Monitoring
- Lighting Mode Control and Monitoring
- Lifts, Escalators & Travelators Control and Monitoring
- Network Diagnostics
 FAS
- LFAP Health Status
- Fire Alarm Signals
- FM 200 Signals -Continued-

9. Control and Monitoring function
 Temperature and humidity control
 Equipment command & status monitoring, events/alarms log
 Mode Control-command and monitoring
 Safety interlock functions
 Equipment Start up Shut down sequence
 Hardware & Network diagnostics
 Station lighting control
 Monitoring of
-LV system
-Room temperature
-Generator
-Gas suppression system, Station entry doors etc.

10.  Station Entry Doors
- Control commands and status monitoring
- Open during emergency mode
- Power supply status
 Chilled Water System
- Primary and Secondary data exchange
- Monitor Energy consumption
 COM
- Direct connectivity of remote buildings, ECS-MSN
- Protocol RTU, ECS –SCADA

11. Type of Stations and numbers
Underground, above ground,
elevated stations
 ECS has also been provided for
tunnels, annex, depots, car parks and
EEP (emergency egress points)

12. Systems covered
 ECS is connected to the following-
 Station Air conditioning system
 Station Ventilation system
 Station Smoke Extract system
 Station Lighting Control system
 Lifts and Escalators
 Auto Doors at Station Entrances
 Fire Protection system
 Uninterruptible power supply
 Low Voltage system

13. Typical Quantities of ECS controlled items
Item Quantity
No of AHUs & FCUs 660
No of LV switchgear 728
No of Ventilation Fans/smoke fans etc 334
No of Motorized dampers/ Modulating dampers 1652
Chilled water pumps 72
Heat Exchanger 36
Pressurization unit 18
UPS 18
Fire alarm panels 36
Lifts 83
Escalators 139
Travelators 4
Pumps (Water services and dewatering pumps) 98
Lighting control panels 18
Room temperature sensors/ Hydrogen sensors 144
FM 200 signals 251
Generator 6
Station Entry doors 100
Total 4397

14. Technical solution- Key features
 Solid state high reliability Programmable Logic Controllers
 Fully redundant controller with hot standby function
 Can operate at 0 to 60 C and RH of 5 to 95%
 Self contained configurable input output modules
distributed throughout the station plant rooms
 Fully redundant communication network from controller to
input output modules
 High speed communication port for direct connectivity to
external Networks on Modbus protocol
 ‘Third party quality certified’ software program
 Inbuilt diagnostic routines and system health monitoring

15. The Engineer – Dubai Metro Project
Basic block diagram

16. Typical Hardware
 Processors
 Control logic chasis
 Memory modules
 Control Net modules
 Power Supply modules
 Redundancy modules
 Input output modules
 Modbus TCP/IP converter
 Cabling
 Field Devices, sensors/ transducers
 Sheet steel cabinets

17. Major contractors & suppliers
E&M Works
 Al Futtaim
 Hitachi
 ETA
 ETA-Melco
 Build force
 CML
ECS Works
 ETA
 Rockwell
 Avancion
 Honeywell
 Trends

18. Inside view of ECS cabinet

19. Examples of ECS connected equipments
E&M Air Handling Unit Chilled Water Plant

20. High resolution field devices/sensors
Valve actuator Temperature transmitter Differential pressure switch

21. Field devices at work

22. Site Safety
 Lock-out tag-out must be implemented during ECS
testing and commissioning to ensure safety during
remote operation from ECS
 Safety lessons/trainings should be provided for all
staff.
 Site safety walks should be conducted and daily
safety check lists should be completed by
supervisors.

23. Lessons Learnt- improvements
 Direct Digital Controller to Programmable Logic Controller in G
 Direct Modbus connectivity to SCADA system eliminates use of
BACnet to Modbus data concentrator
 Fully redundant network
 Elimination of hard-wired interface between LFAP-VAC &
essential equipment as the ECS system is fully redundant
 Increased adaptability to site situations and future modifications
 Reduction in installation, testing and commissioning duration
 Reduction in integrated test duration
 Reduction in wiring and containment thus eliminating
congestion of services