TECHNICAL SPECIFICATION

ELECTRICAL INSTALLATION
GENERATING SYSTEM

1. Description

1.1 The emergency generator shall include, but not be limited to, the followings:

1. Complete diesel engine/generator set including radiator, anti-vibration

mountings, holding down bolts, etc.
2. Complete exhaust system including all silencers, catalytic converter Filter / diesel
soot Filter, suspension and thermal insulation.
3. Complete fuel delivery system including a daily fuel tank, fuel storage tank
including fuel meter, fuel feed cabinet, all pipes, valves and vent pipe, where
required.
4. Control panel complete with all accessories and control to provide a complete
and operable system.
5. DC electric starting system.
1.2 The generator set shall have provision for both manual and fully automatic starting
facilities and be capable of transferring the 100% full designed connected load in the
event of a complete mains failure or a deviation outside the acceptable limits and to
do so in not more than 10 seconds.
1.3 The generator set shall be suitable for cold starting and adequately sized to meet the
load requirements under the worst-case considerations. Details of the sizing shall be
submitted for approval. The sizing of the generator set shall take into account of, but
not be limited to, the following factors:-
1. Derating factors (altitude, ambient temperature, power factor, etc.)
2. Impact load.
3. Transient voltage dip
4. Momentary overload
5. Regenerative power
6. Rectifier loads
7. Phase loads unbalance
8. Instability due to interaction between voltage regulation systems.
9. A 10% overload capacity in excess of the nameplate continuous rating for one
hour in any 12 consecutive hours of full load operation.
1.4 The electrical essential loads include FH/HR Pumps, Sprinkler Pumps, Fireman Lifts,
Passenger Lifts Homing, Emergency Lighting, Fire Shutters, Fire control panel and
other load as indicated on specification, drawings and equipment schedule. All items
above shall be maintained for continuous operation for six hours in case of mains
supply failure.
1.5 Except as modified by statutory requirements and the Contract Documents, comply
with the latest applicable provisions and the latest recommendations of the following:
1. Generally
BS ISO 8528
2. Alternator:

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a. BS ISO 3046, IEC 60034, BS5000 , NEMA MG-1-22

b. BS 2869, ASTM D396
3. Battery Charger:
BS EN 50171, BS EN 50172, BS EN 60146, U.L. 1236
4. Engine Generator:
a. Legislations and laws.
b. U.L. 2200
5. Control and Status Panels:
NFPA 110
6. Testing:
a. NETA
b. BS ISO 8528
1.6 Equipment suppliers shall have local representation and shall have been actively
engaged in the assembly, installation and service of this equipment for emergency
power purposes for a period of not less than 10 years in the Job Site area.
1.7 Equipment suppliers shall have full parts backup and a 24 hour per day, 365 days per
year service availability for this equipment.
1.8 The emergency generator shall be adaptable to the emerging technologies that may
be required with new regulations. As a minimum, the generator shall comply with EPA
off-road diesel engine Tier 3 standards
1.9 Provide a 150mm high concrete plinth beneath each generator.
1.10 Provide a concrete curb under each door of the generator room to prevent migration
of spilled liquids out of the room.

2. Particular Requirements on Quality Assurance

2.1. The Electrical Sub-Contractor shall ensure the compatibility of various components and
accessories. Generators will be complete set manufactured & tested in G7 country.
2.2. Generators will be complete set manufactured & tested in G7 country.
2.3. Notwithstanding any description or detail (implied or otherwise) included hereafter, the
generator set shall comply with all the necessary requirements of the FSD, EPD and
any other relevant regulations to enable the generator set to be operative.
3. Site and Service Condition

The service conditions are as follows:

Installation site : indoor, dusty room and high humidity.
Altitude and Temperature & relative humidity (see Climatic Conditions and Geographic
Conditions)
Equipment shall be suitable for use in tropical climatic area, and shall be capable of
operating at its full ratings in the service conditions mentioned above.

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4. Submittals

4.1 As a minimum, submit the following for approval at the appropriate stages of the works:
1. Detailed schedule of equipment and components.
2. Detailed and coordinated shop drawings on Generator Room equipment layout,
with requirements on engine exhaust system, fuel supply system, cooling
system, including calculations, pipe sizes, construction details, installation
details, etc.
3. Electrical control wiring diagrams showing details of all wirings internal and
external to the generator control panel, together with terminal numbers for cable
terminations to external equipment.
4. Detailed calculation on generators sizing.
5. Detailed calculation on battery sizing.
6. Detailed calculation on flue pipes sizing.
7. Equipment static and dynamic weights.
8. Detailed calculation on anti-vibration mounting requirements.
9. Builder's works requirement.
10. Proposal on testing procedures (including dummy load test) and report format
for testing of the generator set at the manufacturer's works and on site.
11. Proposal on predetermined sequence of starting methods to achieve sequence
starting of essential equipment.
5. Design and Construction of Generator Set

5.1 General
1. The generator set shall comprise a diesel engine directly coupled to an
alternator and mounted in line on a common base-frame.
2. Equip the generator set fully for radio interference suppression to BS800.
3. Enclose or guard totally all exposed moving parts, except manually operated
controls, to prevent accidental contact by personnel. All guards shall be
detachable.
4. Treat all exposed ferrous metal surface of the generator set, underframe and
ancillary equipment with rust-proofing primer paint undercoat and finishing coat.
Hot face part shall be coated with heat resisting paintwork which can tolerate
high temperature up to 650°C without deterioration.
5. The overall Generator installation shall be capable of delivering the electrical
power (kW and kVA @ 0.8pf) noted in the particular specification, drawings or
schedules to the electrical systems. Where electric Fans etc. are used as part
of the generator installation (for instance as radiator fans) then the overall output
shall be equal to the specified value plus the power required for those electric
fans etc.
6. Unless noted otherwise in the particular specification, drawings or schedules,
the generator shall conform to the G2 requirements of BS ISO 8528

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7. The diesel engine-generator sets shall be capable of single step load pick up of
100% of nameplate kW and power factor, less applicable derating factors, with
the engine-generator set at operating temperature.
8. The BMS shall be linked to the generator system though Modbus interface to
monitor the key parameters and system status.
5.2 Engine – for Ultra Low sulphur diesel oil
1. The engine shall be suitable for use with light diesel fuel oil to BS2869 Class A1
or A2 diesel fuel commonly available at the place of installation, water cooled,
four stroke, direct injection, naturally aspirated or pressure charged and
complying with BS5514. Engine shall be of number 2 ultra low suliphur diesel
oil.
2. The engine shall be rated for continuous duty to BS5514 and sized to match the
continuous rating of the alternator, with overload capacity as specified hereafter.
3. Engine crankshaft speed shall not exceed 1500 rpm. The normal direction of
rotation shall be anti-clockwise.
4. A mechanical over-speed tripping mechanism shall be provided to shut off the
fuel supply in the event of 15% over-speed.
5.3 Alternator
1. Design and construct the alternator to meet the appropriate sections of BS4999
and BS5000.
2. The alternator shall be of brushless type, with the rotating field excited from an
a.c. exciter and rotating rectifier unit, and with the exciter controlled by solid-
state automatic voltage regulator as specified hereafter.
3. The alternator shall be rated to suit local conditions and specially impregnated
for tropical duty.
4. The rotor and stator of the alternator shall have Class F insulation.
5. The alternator characteristics must be matched to the torque characteristics of
the engine, in such a manner that with full load connected to the alternator, the
alternator can utilize all the available engine power without exceeding it.
6. The alternator must be capable of withstanding an over-speed of 20% above
synchronous value.
7. The alternator must be capable of withstanding an unbalance load with the
current in one phase more than the other phases by 60%.
8. The alternator shall be drip proof to IP23 of BSEN 60529.
9. The alternator shall be built in with thermostatically controlled heater and with
manual isolating switch at the control panel. The heater shall be cut off when
the alternator is in operation.
10. The alternator shall be capable of withstanding the short circuit current with the
output terminals short circuited for 3 seconds without any damage to the
generator.

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5.4 Radiator
1. The engine shall be water cooled by means of a matching heavy duty radiator
complete with belt-driven fan, coolant pump, thermostat temperature control
liquid-cooled exhaust manifolds, intercooler, coolant corrosion resistant filters
suitably designed to suit the site conditions.
2. The radiator shall be mounted on the same base frame supporting the generator
set where a set mounted radiator is required.
3. The radiator shall be fitted with duct adapter flange to enable the ventilating
ductwork to be attached to the radiator. A section of ductwork complete with
flexible connector shall be installed between the radiator and the metal louvers
provided. Ductwork shall be constructed of galvanized steel sheets in
accordance with Heating and Ventilating Contractor's Association (HVCA) DW
144.
4. The fan rating shall be adequate to allow for the additional resistance to airflow
of the ductwork, silencer, and louvers, if fitted.
5. Corrosion inhibitor shall be added to the cooling system.
5.5 Noise/Sound Attenuation Generally
5.5.1 Requirements:
1. Sound attenuation shall be provided to the generator installation
(Rooms/enclosures, exhausts, cooling systems, air inlet/discharge etc.) to
ensure noise levels do not exceed the sound levels noted by the particular
specification, drawings and schedules.
2. Where the Particular specification schedules and drawings do not give specific
requirements the whole installation shall be provided with silencers, attenuation
and acoustic treatment to ensure noise levels of 68dBA are not exceeded at 3m
from the:
a. exhaust discharge
b. any part of the Exhaust pipe and silencer arrangement that is outside of the
Generator room/enclosure.
c. perimeter of the Generator room (this includes the Roof (or ceiling) the walls
and the Floor when the unit is not mounted on a ground bearing slab)
d. In any habitable space or plant room in the vicinity of the generator room.
3. When considering the overall requirements for the noise levels, the Contractor
shall note that the specified Maximum noise levels are to be achieved when all
generator backed plant (Including, HVAC Fans, chillers etc, and, Public Health
Pumps, compressors etc.) are running normally and their noise levels are added
to that emanating from the generator installation.
5.5.2 Results Testing and submittals
The Contractor will be required to carry out Noise levels studies to prove the generator
installation complies with the specified requirements. These studies shall include
Testing of the noise levels achieved and submittal of a report to the Engineers.
5.6 Coupling Arrangement and Anti-Vibration Mountings
1. The diesel engine shall be directly coupled to the generator, which shall be of

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the single bearing type.

2. Isolate the generator set at the base by means of combination spring type
isolators and neoprene pads. Provide isolators of not less than 98% efficiency
of a sufficient quantity such that each is loaded to not more than 75% of its rated
value. Provide a minimum static deflection of 75mm
3. Anti-vibration units of the spring type shall be mounted below the base plate so
that the complete installation can be located on a solid concrete plinth without
transmitting vibration to adjacent apparatus or any part of the building.
6. Design and Construction of Ancillary Equipment

6.1 Exhaust Silencers and Flue

1. The flue exhaust system shall comprise exhaust silencer, expansion bellow,
hangers, piping, clams, flange couplings, heat resisting jointing, and items
shown on Drawings.
2. Telescope type exhaust flue pipes shall be used for this project. and operation of
the telescope type flue pipes shall comply with all relevant statutory
requirements.
3. Flange couplings with heat resisting jointing shall be used to for all connections
in the flue exhaust system.
4. A residential type silencer shall be used. The silencer shall be of chambered
construction, complete with moisture trap, exhaust drain, adequately sized to
assure proper operation without excessive backpressure when installed. The
silencer shall be designed to reduce the emitted noise to a level to cope with
any special acoustic requirements as stipulated by Environment Protection
Department.
5. Stainless steel expansion bellows, sized to match the engine and exhaust
silencer shall be provided for installation between the diesel engine and the
associated silencer.
6. A flue pipe complete with stainless steel expansion bellows, all adequately
sized, shall be connected beyond the silencer to discharge the flue outside the
generator room. The flue pipe shall be constructed of black steel pipe to BS1387
Class 'B'.
7. Bends in flue pipe shall have a minimum radius of three times the diameter of
the pipe.
8. The entire system from the exhaust manifold to the end of exhaust pipe, except
the stainless steel expansion bellows, shall be provided with at least two coats
of heat resisting paintwork.
9. The entire system shall be insulated with non-combustible insulating material
complying with BS476 wrapped on galvanized metal mesh and supported on
25mm hot dip galvanized mild steel air spacing stool strips such that a 25mm
air gap is maintained around the flue.
10. The finish of all flue pipework and silencers shall be stainless steel cladding of
not less than 2mm thickness.
11. Spring type hangers with an approved design shall support the entire system.

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12. Installation of two silencers in series (a ‘critical rated’ reactive type and a
standard absorptive type) to each generator is required to meet the noise design
goals.
 A minimum 1675mm long ECI fully lined super critical 150NB silencer with
fully lined internal tubes installed in series with:
 A minimum 1,730mm long ECI 150NB absorptive
13. The exhaust silencers shall be installed in accordance with the manufacturer’s
recommendations and as close to the engine as possible in a section of
pipework isolated from the main engine. The static pressure associated with the
silencers should be checked by the contractor / supplier to ensure that the
silencer installation does not impede effective operation of the exhaust system.
6.2 Air Intake And Discharge
6.2.1. Air Intake and discharge louvers shall be provided and shall accord with the following:

1. The finished colour of the louvre shall be agreed with the Architect where it is
not given in the particular specification, drawings or schedules.
2. Be weatherproof to prevent wind driven rain or rain carried on the air stream
entering the building or the louvers.
3. Be provided with guards to prevent entrance by small animals, rodents birds
etc.
4. Shall, when used in conjunction with the Attenuators, cooling fans etc. permit
sufficient air flow through the Generator room for cooling purposes.
6.2.2. The Contractor shall note that the size of the ductwork, attenuators, and louvers
indicated on the drawings is based on generic data. He shall ensure that all ductwork,
louvers, attenuators etc. are adequately sized for the required air flow and noise levels.
6.2.3. Dampers shall be provided on the air inlet and discharge air paths where required by
the particular specification, drawings or schedules. Unless noted otherwise these shall
be arranged such that:
1. They are powered closed when the generators are not running.
2. They spring open on failure of their power supply and when the generators are
signalled to start.
3. They shall be fitted with Auxiliary contacts to indicate their position (open or
Closed) which shall be monitored by the BMS system and or the Building
automation systems.
4. They shall be inhibited from powering closed when the generators are running.
5. Motorized louvers shall be galvanized frame and blade construction with blade
seals installed within the frames. Motorized louvers shall be provided with louver
control wiring boxes which shall incorporate time delay relays and ventilation
fan controls. Provide an access hatch to allow for inspection and maintenance
of each louver motor and spring mechanism where required.
6. They shall be able to work incorporated with Fire extinguish system of generator
room.

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6.3 Fuel System

1. Day Tank
 A fuel storage day tank shall have a capacity minimum for at least 8 hours
full load emergency backup located adjacent to this respective diesel
generator set. Should the required 8 hours storage capacity exceeds 700
litre, additional separated fire compartment to FSB requirement shall deem
to include in this contract shall be incorporated to house the fuel tank.
 High/low level indicators shall be installed at the engine control panel. An
audio and visual alarm system shall sound when the fuel is at dangerously
low level.
 A manual hand pump shall be provided.
 The system shall be complete with fuel supply and return pipes suitable size
to transfer the fuel supply from the day tank to the engine.
 Overflow/vent should be installed to comply with the local requirement.
 Filter shall be provided at the draw-off line. Alarm shall be raised at the
BMS, and simultaneously, audible and visual indication provided at the day
tank vicinity to alert maintenance if the day tank is at high level.
 The tank shall be manufactured in accordance with BS 2594 and fabricated
from good commercial quality galvanised steel sheet of 6mm thickness.
The ends of the tank and all outlets shall flange and electrically welded
throughout and slag/spatter removed.
 The voltage-free contacts shall be provided for connection to the Building
Management System (BMS).
 All installations shall be carried out in accordance with CP40 and all local
authorities’ requirements inclusive of liaison, submission, endorsement and
payment of all fees and charges for the testing and inspection on the whole
installation.
 Fuel oil shall be of Class A fuel to BS 2869.
 All tanks shall be completed with drip tray and leakage sensor complete with
alarm.
2. Bulk Storage Tank and Piping
 The complete system shall include design, supply, and installation, testing
and commissioning the bulk storage fuel tank, pumps, piping, valves and
control system.
 Submission and approval shall be obtained prior to installation.
 Design suitability. The complete system shall be designed and constructed
for the conditions of use, and in particular:
- It shall be compatible with the particular liquid or any other
component with which it may be in contact;
- It shall be resistant to any heat to which it may be exposed; and

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- Where subject to corrosion, it shall be sufficiently resistant to

ensure an acceptable life.
- It shall comply with Fire safety Bureau requirement, relevant
British standards / Singapore standards.

 All tank shall be completed with leakage collection and leakage sensor
complete with alarm.
 Flexible tube. Flexible tubing, piping or hose may be used only on condition
that:
- The use of such tubing is avoidable because of the need to
provide for movement or to reduce the effect of vibration;

- The tubing is of flexible metallic, metal-reinforced, armoured or

other construction suitable for the working pressure,
temperature, and the liquid being handled.

 Design and construction: The following general design consideration shall

be taken into account when designing and installing any piping:
- The layout shall take account of the needs for operating access,
maintenance, replacement, drainage, etc. and shall ensure that
any access ways are not impeded.

- Supporting and fixing shall be secure and the piping shall be not
unduly exposed to mechanical damage.

- Protection against corrosion shall be provided wherever

necessary. Particular attention shall be given to outside and
underground locations or to any piping, which passes through or
is embedded in any material likely to induce corrosion.

- Provision shall be made, wherever necessary, for the expansion

or contraction of the piping and its contents.

- Any trench in which pipes are laid shall be drained, and shall be
of adequate dimensions to permit access to valves and fittings.

- Any buried piping shall be protected from superimposed loads,

ground settlement, etc.

- Any necessary electrical bonding and earthing shall be provided.

- Piping shall be painted and/or marked in a manner sufficient to

permit ready identification of its contents.

- Where piping is encased in concrete, means shall be taken to

guard against corrosion and to provide for expansion.

- Leakage sensors shall be included to detect the bulk storage

tank and piping for monitoring purpose.

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- Provide fuel pump control panel that has remote fuel level
indications and High/low level alarm indications with buzzer and
acknowledge button interface with bulk fuel tank.
 Hydraulic Testing of Fuel Bulk Tank and Pipe work:
- Hydraulic testing is refined for the bulk tanks and the associated
pipe work.

- During the hydraulic test, the following test pressure shall be

adopted:

 70 kPa for fuel bulk tank: per BS 2594

 70kPa for the associated pipe work, valves and fittings. Test
for two (2) hours, pressure drop shall not exceed 3%.

- The test shall be last for at least 3 hours without under

deformation and leaking.

- The Sub-Sub-contractor may require any pressure gauge

employed to be tested and calibrated before use. Pressure
gauges with full-scale deflection readings more than three (3)
times the test pressures shall not be used.
3. A complete fuel storage and distribution system shall be provided as specified
herein and as shown on the Drawings.
4. A fuel tank of not less than 500L capacity shall be provided. The fuel tank shall
be fitted with low level fuel switches set to provide 2-stage alarm at 20% and
5% level.
5. The fuel tank shall be manufactured in accordance with BS 799 : Part 5 and
shall be fabricated form high quality mild steel plate of 5mm thick, end dished
and flanged, electrically welded throughout and spatter removed.
6. The fuel tank shall be complete with an inspection cover, fail-safe sight gauge,
protected seal fill cap, flame arrestor, vent cap, sludge drain, level switches,
overspill, main fuel inlet, content gauge, etc. The content gauge shall be of the
dial type, with adequate size scale clearly marked in proportional parts of the
contents, i.e. empty, quarter, half, three-quarter and full. Calibration of the
gauge shall be demonstrated on site.
6.4 D.C. Electric Starting System
1. The generating set shall be equipped with an engine starter motor which shall
be suitable for 24V DC operation, complete with manual and automatic starting
and starter cut-out switch as described herein.
2. The engine starting control equipment shall be arranged to disconnect the
mains operated battery charger to prevent its being overloaded during starting.
3. The starter motor shall be of adequate power for its duty and of "non-hold-on"
type in which the pinion is moved axially to engage with a gear-ring on the engine
flywheel before the starter motor is fully energized. The pinion shall positively
disengage when the engine starts or when the motor is de-energized.
4. The starting equipment shall incorporate a fail-to-start device for automatically

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disconnecting the starter motor if the engine fails to start within a pre-
determined time, say 15 seconds, so as to avoid undue discharge of the
batteries.
5. A total of three consecutive starts, say with 15s duration, and at 5s intervals,
shall be made to start the engine, after which disconnection of the starter by the
fail-to-start device shall operate the visual and audible alarm as specified
hereafter. No further attempts shall be made to start the engine by the automatic
starting system until the fail-to-start mechanism has been reset manually.
6.5 Starting Battery and Charger
1. A 24V d.c. engine starting battery set of nickel-cadmium type of adequate
ampere hour capacity and discharge rate shall be mounted adjacent to the
engine underbase. The battery shall comply with IEC 623 and be capable of
providing six consecutive starts of 15 seconds duration, and at 5 seconds
intervals, without being discharged to a level where damage may be caused to
the battery as advised by the manufacturer. The battery shall be housed in
corrosion resisting container of an approved type.
2. The battery charger shall be constant potential type, complete with d.c.
voltmeter and ammeter, surge suppressor, controls, float and boost charging
selection, battery discharging indication, protection against over-charging and
indication, charger failure alarm. All controls and sensors shall be wired to the
set mounted control panel.
6.6 Engine Heater
The heaters shall be thermostatically controlled and be disconnected whenever the
engine is put into operation.
6.7 Miscellaneous
1. Fuel Injection System
The fuel injection system shall be complete with primary and secondary fuel
filters with replaceable elements, and an engine driven, mechanical, positive
displacement fuel pumps, all mounted on the engine.
2. Lubricating System
Enclosed forced feed lubricating system shall be complete with positive
displacement, mechanical lubrication oil pump, lubricating oil cooler, filters and
dipsticks oil level indicator.
3. Air Cleaner
Replaceable dry heavy duty element air cleaner shall include an automatic
device to give an alarm when the filter becomes clogged.

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7. Control and Protection of the Generator Set and Associated Equipment

7.1 Positions of Control and Adjustment Device

1. All operational controls shall be arranged such that they are grouped together
in a readily accessible and logical position.
2. Setting up devices shall be separately located to prevent unauthorized
adjustment.

7.2 Engine Status Indication

The engine shall be provided with the following status indication as a minimum:
- Oil temperature and pressure
- Jacket coolant inlet/outlet temperature and pressure
- Engine temperatures(at connection points of exhaust flue and inlet/outlet of
turbo charge and at each cylinder)
- Service hours
- Tachometer
- Battery charger ammeter
7.3 Engine Protection
1. The engine shall be provided with the following protective devices and control
as a minimum to effect early warning and/or shut down in the event of:
- Low lubricating oil pressure
- High engine coolant temperature
- Engine over speed
2. The above protection shall be in two stages; it shall give visual and audible
warnings at an initial stage and shall shut down the engine when a pre-
determined danger level is reached.
3. All visual alarms, audible alarms and the associated muting switches shall be
wired to the control panel.
4. The generator set shall be provided with a key operated protection over-ride
switch. The generator set shall be kept running as long as possible irrespective
of faults occurring upon actuation of the key-switch. The key holder will be a
highly responsible engineer.
7.4 Engine Governing and Speed Adjustment
1. Governing
- An electronic speed-sensing governor shall be provided.
- Governor shall sense the actual engine rotation.
- Speed governing shall be to BS5514: Part 4, Type 1, Class A1.
2. Speed Adjustment
- The speed shall normally be preset to ensure rated frequency at full load.
- Provision shall be made for the manual adjustment of speed within the range of
±5% under all load conditions.

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7.5 Voltage Regulation and Adjustment

1. Voltage Regulation
- Provide an automatic voltage regulation system to maintain the output voltage at
the generator's terminal within ±2.5% of its rated value from no load to full load
under steady state condition.
- The performance of the voltage regulation system of the generator shall be of
Grade VR2.23 as specified in BS 4999: Part 140.
2. Voltage Adjustment
Provide a means of adjusting the output voltage to facilitate adjustment of the
machine output voltage at any level within its design parameters.
7.6 Control Panel
1. Provide a wall or floor mounted generator set control panel with suitably
designed and approved supporting framework. Otherwise, it shall be mounted
on top of the generator depends on the actual plant room spaces.
2. Construct the control panel with materials capable of withstanding the
mechanical, vibration, electrical and thermal stresses, and the effects of
humidity, which are likely to be encountered in normal service.
3. Provide protective devices to give protection against the consequences of short
circuits in the control circuitry.
4. Where electrical apparatus is attached to lids or doors, means shall be taken to
ensure continuity of the protective circuit in the form of an earth continuity
conductor of an appropriate size.
5. Install wiring to apparatus and measuring instruments in covers or doors so that
no mechanical damage can occur as a result of movement of the door or cover.
6. Locate adjustment devices not required on a regular daily basis within the
control panel to permit safe operation.
7. The control panel shall contain, but not be limited to, the following:
a. Four poles ACB or MCCB with adjustable trips for generator overcurrent,
earth fault and reverse power relays, controls and indications as specified.
The current rating and breaking capacity of the MCCB shall be compatible
with the generator provided.
b. Meters
- kW meter.
- Frequency meter (range: 45 to 55 Hz).
- Power factor meter
- Hours run meter (range: 9999 hours).
- AC voltmeter with phase selector switch, to monitor generator output
voltage.
- AC ammeter with phase selector switch and current transformers, to
monitor generator output current.
- DC voltmeter to monitor battery voltage.

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- DC ammeter to monitor charging current.

- Non-resettable counter to monitor number of start.
- Non-resettable counter to monitor number of fail-to-start.
c. Push buttons:
- engine start push button
- Engine stop push button
- System reset push button
- Push button to simulate mains failure
d. Red indicating lights with audible alarm :
- MCCB tripped on fault
- Engine overcrank lockout
- Engine overspeed shutdown (2 stages)
- Engine fail-to-start
- Low fuel level (2 stages)
e. Indicating lights without audible alarm:

 Red lights - MCCB closed

- engine control in auto mode
- battery discharging

 Green lights - MCCB open

- engine control in manual mode
- generator on load
- main supply available

 Amber lights - MCCB trip circuit healthy

f. Other control devices:-

- Lamp test button
- Frequency preset device
- Voltage preset device

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- Engine starting control

- Battery charger and associated equipment
- Engine heater control
- Electronic isochronous governor
- Solid state automatic voltage regulator
- "Manual - auto" rotary control switch
- Audible alarm and mutinq switch
- Thermostatically controlled anti-condensation panel heater with manual
isolating switch.
- All necessary relays and dry contacts to provide for remote indications,
engine starting and engine shutdown, generator protection override, etc.
As specified hereafter.
8. System Operation and Performance

8.1 Automatic Operation

1. On operation of the voltage relay with adjustable time delay between 0 to 5
seconds at the upstream of the "Normal' breaker of the ATS in the designated
L.V. switchboard during failure of the mains supply, a signal shall initiate the
start-up system of the engine.
2. On receipt the start signal, the prime mover start sequence shall begin.
3. The generator set shall establish its rated speed and ready for load transfer
within a maximum period of 15 seconds from the time when the start signal is
issued.
4. During this period of time, the designated outgoing circuits connected to the
essential section of the L.V. switchboard shall have been tripped by their under-
voltage relays.
5. When the generator set reaches its rated frequency and voltage, a signal shall
be initiated to open the 'Normal' circuit breaker and close the 'Standby' circuit
breaker. Designated outgoing circuits, which have become open due to the
under-voltage condition, previously, shall close automatically in a pre-
determined sequence when the essential section of the L.V. switchboard is
energized in order not to overload the generator.
6. Should the prime mover fail to start after a period of 15 seconds, the sequence
shall be interrupted for a period of 5 seconds and a further two attempts to start
of 5 seconds duration shall then be made. If it again fails to start, the starting
sequence shall be locked out, an audible and visual alarm given and it shall
remain in this locked out condition until manually reset.
7. Restoration of the mains supply during the starting period shall not interrupt the
starting sequence but shall prevent operation of the load transfer. Subsequent
failure of the mains supply while the generator set is running shall, after
expiration of the 0.5 to 1.0 seconds time delay, cause the load transfer to take
place.
8. On full restoration of normal supply, load transfer and shutting down of the

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generator set shall be either by manual or automatic operation selectable by a

selector switch on the control panel. Upon activation of this command, load
transfer shall take place immediately. The generator sets shall run unloaded for
a short cool-down period of 0 to 15 minutes adjustable and then shut down.
9. The Electrical Sub-Contractor shall provide all equipment, control equipment,
control wirings and accessories to achieve sequence starting of the essential
equipment connected to the essential section of the L.V. switchboard.
8.2 Manual Operation
1. The control panel shall be equipped with an “Auto/Manual” rotary control switch.
The system shall operate as described above in “Auto” selection and shall hold
the existing status of the system until manual controls are effective.
2. When in “Manual” selection, a signal should be sent to the Building
Management System (BMS) to draw the operators’ attention.
3. The generator set shall be able to start manually, by control switches located
on the control panel. Once started and running normally, the generator can be
manually connected to the desired essential load.
4. During the whole of the manual starting sequence, all the loads shall not be
transferred to the generator as long as the mains power remains available.
However, upon actuation of a “Manual Load Transfer” push button, a signal
shall be initiated to open the “Normal” circuit breaker and close the “Standby”
circuit breaker to enable load transfer as per in the automatic operation. By re-
setting the “Manual Load Transfer” push button, the load shall be transferred
back to the mains supply.
9. Earthing

9.1 Provide an earthing terminal in the Generator Room for the earthing of the generator
set.
9.2 The generator frame, generator neutral, L.V. switchboard, cable trays/ladders, etc.
shall be individually connected to the earth terminal in the Generator Room. The size
of the protective conductors shall not be less than 6mm by 25mm.
10. Warning Sign

A warning sign stating "ATTENTION – ENGINE STARTS AUTOMATICALLY

WITHOUT WARNING. DO NOT COME CLOSE" in lettering not less than 50mm high
with Vietnamese translation shall be provided and fixed at a prominent position in the
Generator Room.
11. Schematic and Control Wiring Diagram

11.1 The electrical schematic diagrams for the essential power supply distribution shall be
fixed in wooden frame with transparent panel of suitable size at a prominent position in
the Generator Room.
11.2 One complete set of control wiring diagram shall be provided inside the control panel.

12. Installation

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12.1. The Electrical Sub-Contractor shall provide the acoustic treatment such that the sound
pressure level both inside the lot and adjacent to the site boundary, due to the operation
of generator set shall not exceed the permissible noise level as required by the
Environmental Protection Department (EPD) and acoustic specification.
12.2. The Electrical Sub-Contractor shall be responsible for obtaining Dangerous Goods
License from the Fire Services Department and installation approval from the
Environmental Protection Department.
12.3. The Electrical Sub-Contractor shall submit the anti-vibration spring loading calculations
at earliest stage for Architect approval.
13. Engine Cooling

13.1. The hot air from the radiator shall be directed out of the radiator through a louver panel.
The necessary ductwork complete with anti-vibration flexible joint and silencer shall be
provided by the Electrical Sub-Contractor. The method of fixing the duct shall be
proposed by the Electrical Sub- Contractor and approved by the Architect.
13.2. All ductworks and materials shall be provided, including linings, adhesives, flexible
ducts, flexible connections, gaskets, sealants, etc. The complete installation shall
comply fully with all the requirements of the Fire Services Department and shall satisfy
BS 5588: Part 9 and BS 8313 in respect of resistance to the penetration of fire and
spread of flame and smoke.
13.3. All metal ducting shall be constructed to the recommendation of the Heating and
Ventilating Contractor's Association (HVCA), U.K. Ductwork Group in their Publication
DW144 or the latest edition.
13.4. The cooling system shall be fitted with the manufacturer's recommended anti-corrosion
solution.
13.5. The Electrical Sub-Contractor shall ensure that the pressure drop across the attenuator
is compatible with the available static pressure of the radiator fan.
14. Installation of Exhaust System

14.1. Exhaust manifolds shall be provided on the engine terminating at the outlet(s) from the
turbo charger.
14.2. The exhaust system shall comprise flexible exhaust pipe for connection to the engine
outlet, high attenuation mild steel pipe, residential primary and secondary exhaust type
silencers and flue. The primary silencer shall be located in a position as close to the
engine as possible and the secondary silencer shall be located in the exhaust pipe run
close to the primary silencer. The distance between two silencers shall give the best
possible exhaust silencing results, as recommended by the manufacturer.
14.3. The exhaust pipe shall complete with mating flanges, nuts, bolts and flexible bellows
and shall be insulated with heavy-duty stainless steel cladding on the outside. Brackets
and supports of adequate strength shall be provided to support the exhaust pipe,
silencer and all other fittings.
14.4. The Electrical Sub-Contractor shall ensure that the exhaust system is designed to suit
its particular application. Full details shall be submitted in respect of construction,
cladding and temperature calculations at the exhaust outlets, fully documented and
certified. The exhaust shall be protected against the ingress of rain and water.
14.5. The insulation shall ensure that the temperature on surface of the cladding is safe to

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touch. Otherwise the Electrical Sub-Contractor shall provide the necessary additional
protection.
15. Cable Termination

Termination identification shall comply with the requirements of BS 822: Part 6.

Terminals shall be fitted with compression type cable sockets and shall be housed in a
suitably earthed metal enclosure, having provision for external flexible cable
connections. Locking washers shall be provided on the terminals to ensure that
connections will not loosen under normal working conditions.
16. Installation of Fuel System

16.1. Notwithstanding any description or detail (implied or otherwise) specified herein, the
Electrical Sub- Contractor shall ensure that the fuel system installation complies with all
necessary requirements of Fire Services Department (Dangerous Goods Section) and
any other relevant regulations.
16.2. The Electrical Sub-Contractor shall obtain written approval from Fire Services
Department before any site work is commenced by preparation of details for
submission made through the Architect.
16.3. Before fuel tank is installed, all rust and scale shall be removed from the external
surface immediately before applying one coat of red lead to BS 2523 Type B followed
by two coats of bituminous paint. Where damage is sustained to the protective coating
due to handling, etc., such coating shall be made good by the Electrical Sub-Contractor.
16.4. All pipework shall be free from burrs, rust and scale and shall be thoroughly cleaned
before installation. The open ends shall be plugged with purpose made metal or plastic
caps during the installation period. The use of wooden plugs, paper, cotton waste, etc.
for this purpose is forbidden. All pipes shall be rigidly fixed with suitable brackets at 1m
intervals.
16.5. All pipes shall be properly painted with two coats of primer and two coats of final finish
with color to be approved.
16.6. All pipework underfloors and any other pipework likely to be in direct contact with
concrete, shall be coated with a bitumen compound and wrapped in polythene before
being concealed.

16.7. The vent pipe shall discharge upwards in the open air at a location acceptable to the
Architect. The upper end of the vent pipe shall be terminated with a flame trap of
adequate construction to preclude the entry of birds, insects, leaves, etc.
16.8. The Electrical Sub-contractor shall supply and install rotary fuel transfer pumps
complete with all necessary accessories including strainers, check valves, gate valves,
etc. which comply with the following requirements:-
1. The pumps shall be positive displacement type, with high quality cast iron body,
high tensile steel shafts and built in internal relief valve.
2. Each pump shall be capable of delivering 'light' diesel fuel oil at 300 kPa 950
rpm maximum. For each pair of pumps a manual switch shall be provided to
select the pump running mode as ‘duty’ or ‘standby’ respectively.
3. The coupling motor shall be flame proof 3 phase, 50 Hz, 400V with no volt

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release and overload protection. It shall have a manual/auto/off switch with

connections for remote start/stop operation by the level switch at the daily
service tank. The duty pump shall be actuated when the fuel level in the daily
service tank fall below 30% of the tank capacity, cut off automatically when the
tank is 90% full. The pumps shall also be inoperative when the fuel level in the
underground storage tank falls below a pre-set level.
4. Audible alarm shall be given off under the following conditions:
- Underground storage tank fuel level low, 7.5-hour and 6-hour remaining fuel
levels.
- Pump fail to start
5. The Electrical Sub-contractor shall supply and install a composite pump control
cubicle in the pump room incorporating the starters, safety and protection
devices, all necessary wiring work, relays, fuel level control and alarm, push
button and indication lights. The cubicle shall be of wall-mounted type, type of
protection EEx d flameproof enclosures for operation in Zone 1 hazardous area
as classified IPMCSP and IP 65 enclosure to BS EN 60529. The Electrical Sub-
Contractor shall submit drawings and the official certificate issued by BASEEFA
of the cubicle for the Architect's approval before manufacture commence.
6. Upon acceptance of field testing and prior to final payment, the main fuel oil tank
and the day tank shall be filled with suitable fuel oil by the installing contractor.
7. Provide a concrete curb around the fuel oil day tank to contain the full capacity
of fuel plus 50% in the event of a day tank leak.
8. Provide a leak detection system for fuel containment and connect to the Building
Management System for monitoring. Provide an LV volt power supply from
nearest emergency panel location.
9. Provide a hand pump for priming
17. Power Cables and Associated Cabling Facilities

17.1. General
Power cables are mainly for electricity supply and distribution. They shall be
manufactured under BASEC license or equivalent quality surveillance scheme (e.g.
CENELEC Harmonization Scheme) and bear BASEC marking or the appropriate
marking of the equivalent quality surveillance scheme (e.g. CENELEC HAR).
Cabling facilities will include cable ducts, cable trays and cable ladder.
Each type of cables specified shall have been certified by an internationally recognized
testing laboratory that it has been designed and manufactured to the appropriate BS
publication.
When applicable, the current carrying capacities and voltage drop of cables shall be
equal to or better than those tabulated in the IEE Wiring Regulations, with ratings
adjusted to suit local conditions, viz. grouping, maximum ambient temperature, etc.
As a minimum, submit the following for approval at the appropriate stages of the Works:
1. Detailed schedule of equipment and components and manufacturer's data,
including manufacturer's type test certificates and testing documents.
2. Cable routing drawings showing the coordinated routing of cables, the disposition

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of the cables on cable trays/ladders or trunkings, methods of fixing of cable

trays/ladder, trunking and cables, etc.
3. Cable straight joints and tee joints installation methods.
4. Builder's works requirements.
17.2. Types of Power Cables
Power cables for supply and distribution shall be one or a combination of the following
as specified in the Specification or on the Drawings:
1. BS 5467, IEC 502, IEC 811 single-core, two-core, three-core or four-core,
600/1000V, cross- linked thermosetting (XLPE) insulated, PVC sheathed,
armoured cables, with conductor operating temperature not exceeding 90ºC;
2. BS 6724 (table 11 to 18) single-core, two-core, three-core or four-core,
600/1000V, low smoke, halogen free (or low smoke zero halogen), cross-linked
thermosetting (XLPE) insulated, armoured cables, with conductor operating
temperature not exceeding 90ºC;
3. BS 6724 (table 11 to 18) single-core, two-core, three-core or four-core,
600/1000V, fire resistant, low smoke, halogen free (or low smoke zero halogen),
cross-linked thermosetting (XLPE) insulated, armoured cables which shall in
addition meet category CWZ of BS 6387 or equivalent international standards
for enhanced circuit integrity under fire conditions;
4. BS EN 60702-1, IEC 702-1, IEC 702-2 two-core, three-core or four-core 500V,
mineral insulated cables (light duty grade), with sheath operating temperature
not exceeding 70ºC;
5. BS EN 60702-1, IEC 702-1, IEC 702-2 single-core, two-core, three-core or four-
core, 75V, mineral insulated cables (heavy duty grade) with sheath operating
temperature not exceeding 70ºC;
6. BS 6346, IEC 189, IEC 227 single-core, two-core, three-core or four-core,
600/1000V, PVC insulated, PVC sheathed, armoured cables, with sheath
operating temperature not exceeding 70º; and
[Note: All above maximum operating temperatures were derived at an ambient
temperature of 30ºC.]

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