MANSIÓN BARBARIANA

The diesel engine shall be 4-stroke, either normally aspirated or supercharged and after-cooled, water after-cooled, equipped with the following :

- Heavy duty air-cleaner, with service indicators - Crank case breather

- Lubricating - oil engine driven pump

- Lubricating - oil simplex filter, with replaceable elements - Lubricating - oil cooler

- Engine - driven jacket water pump - Fuel filter, with service indicators - Flexible fuel lines

- Fuel priming pump

- Dry exhaust manifold, fitting and flange - Flywheel and flywheel housing

Air filters shall be suitable for use in the environmental conditions which are likely to arise occasionally, with the atmosphere highly polluted by blown sand. They shall be fitted with an ‘Air filter condition’ indicator of the vacuum type which shall be fitted to the air inlet manifold.

3.3 Cooling

Thermostatically controlled bypass valves shall be fitted to the engine cooling water system to maintain cooling water at optimum temperature.

3.4 Governor

The governor shall be Electronic type. It shall control the speed within the limits laid down in the respective Standards.

3.5 Engine shut - off.

The engine shall be fitted with a mechanically operated device which will shut off the fuel supply to the engine when any of the specified alarm conditions occur. The device

shall be fitted with one normally open and one normally closed contact which will trip and lock-out the generator circuit breaker in the event of the automatic device operating. Micro switches shall not be used in any direct current circuit nor in any inductive circuit.

3.6 Starting System

The electric starting equipment shall be so designed that :-

(a) at engine speeds in excess of the minimum firing speed it shall be impossible to complete the starting circuit and

(b) not more than three consecutive attempts to start may be made in any period of 1 minute, each starting period and the period between such consecutive attempts being automatically timed controlled by the equipment. At the failure of the third attempt the starter circuit shall be locked out pending manual

The generator shall be complete with all necessary cooling fans, excitation and voltage regulating equipment. The excitation system shall not include a commutator.

The generator shall be star connected.

The generator shall be capable of maintaining the continuous maximum rated output when operating within +/- 1% of rated voltage and at rated power factor.

The critical speed shall exceed twice the overspeed test value.

All windings shall be tropicalised and suitably impregnated to withstand the site ambient conditions.

The generator shall meet the following requirements : - IEC 34/1 standard requirements

- Class H insulation with tropicalisation and anti-abrasion - Three - phase sensing.

- Volts per Hertz, generator mounted, digital automatic voltage regulator, three phase sensing , assuring less than +/- 1% voltage regulation

- Adjustable voltage droop for parallel operation

- Adjustable voltage gain to compensate for engine speed droop and line loss.

- Less than 50 Telephone Influence Factor (TIF) - Less than 3% Total Harmonics Factor (THF)

- Radio interference suppressed to the limits specified in BS 800 The generator shall also be equipped with manual voltage control.

3.7.1 Exciter

The core and poles of the exciter shall be made of high permeability low loss steel stamping tightly clamped and secured to minimize magnetic noise. The characteristics of the exciter shall comply fully with the operational requirements of the alternator in matching the required loading conditions. PM excited generators shall be provided.

3.7.2 Ventilation of generator and exciter.

The generator and exciter shall incorporate shaft mounted fans of sufficient capacity to provide the machine cooling effects necessary to comply with the temperature requirements of the Specification when operating in the specified ambient conditions.

3.7.3 Voltage Regulation

Continuously active, quick acting automatic excitation control equipment responsive to the generator line to line voltage and loading conditions shall be provided to maintain the alternator voltage within the prescribed limits. Equipment will be based wholly on static state devices. Variable Regulation capability regulators shall be preferred.

Diode monitor and loss of excitation protection shall be provided.

The equipment shall include all selector switches, indicating instruments, rectifiers, resistors and any other auxiliary components necessary for the satisfactory opeation of the plant.

A voltage setting device capable of adjusting the required voltage in steps of 1 volt between the limits of 90% and 110% of normal voltage at any load within the rating of the machine shall be mounted on the control panel.

When the generator maximum continuous load at rated power factor is rejected, the regulator equipment shall be capable of limiting the generator momentary over voltage to a value not exceeding 125% rated voltage and shall restore the voltage to within 1%

of the nominal present value within 3 seconds.

Over-voltage/undervoltage and overexcitation protection shall be provided.

3.8 Set Mountings

The diesel engine, the generator and exciter, and the radiator shall be mounted a common welded steel bedplate. Where flange mounted generators are not employed, the bedplates shall be stress relieved before machining.

Lifting points shall be provided on the bedplate.

Suitable anti-vibration mounting shall be supplied for the diesel generator unit, and all set mounted ancillary apparatus.

Flexible connections shall be provided to all exhaust, air, fuel and water piping to avoid fracture due to vibration and to minimize conduction of noise.

Any necessary foundation bolts shall be supplied under this Contract.

3.9 Safety Guards.

All moving parts shall be adequately guarded in accordance with BS 1649 and to the satisfaction of the Engineer, in order to prevent danger to personnel.

3.10 Generator set control equipment

The control equipment is designed to start and stop the set automatically from a remote signal.

The signal will be issued by the Automatic mains failure panel as described elsewhere.

The generator set control equipment shall be set mounted and shall be based on microprocessor based system to provide maximum system flexibility

The control function shall be provided with an OFF/ MANUAL/AUTO/COOLDOWN STOP switch.

3.10.1 The following digital measuring instruments with liquid crystal display shall be fitted :

- an ammeter - 3 phase

- a voltmeter - 3 phase - - a 3 position ammeter/voltmeter selector switch - a frequency meter, in Hz and rpm

3.10.2 Automatic shut-down and lock-out circuits shall be fitted for : - low oil pressure

- Over voltage/Under voltage - Low coolant level

- Over current - Reverse power

3.10.3 Indicator lamps shall be fitted, together with a lamp-test push-button for : - low oil pressure shut down

- high water temperature shut-down - overspeed sit-down

(a) break the closing circuit of the circuit-breaker.

(b) make the tripping circuit of the circuit-breaker.

(c) stop the engine.

(d) close the voltage free contact for a remote alarm.

Simultaneously, an audible alarm shall be given, and the cause of the stoppage shall be displayed and remain displayed on the control panel and the building management system until the alarm device is manually re-set.

When the control selector switch is in the AUTO position, the audible alarm shall be operative.

The control panel shall have a self-diagnostic feature to asses the condition of the various senders and sensing components.

An adjustable run on “off load” timer, shall be fitted to provide cool down running.

All individual circuits such as voltmeter, shutdown circuits etc. shall be adequately protected by fuses.

All control wiring shall be carried out in PVC insulated cable termination and relative terminals shall be clearly marked.

Engine wiring shall be protected by non-metallic conduit.

The control equipment shall also include a breaker as shown on drawings complete with short-circuit magnetic and thermal overload trips, separately housed in a sheet steel enclosure adjacent to the control panel. A shunt trip & Auxiliary contacts shall also be provided. A separate enclosure fixed on the breaker, enclosure with busbars extending from the breaker shall be provided and the outgoing power cables shall be terminated on the busbars.

Separate busbar cubicle must be provided to enable termination of multicore cables.

4.0 TESTING

The set shall be subjected to the following works tests at the factory prior to Shipment. All Certificates must be submitted for prior approval. The same tests shall be repeated at the Supplier’s local facility before delivery the set to site.

(1) General inspection of equipment to check its compliance with specification (2) Timed Start from operation of push button to acceptance of full load.

(3) 1/2 hour 50 % load 1 hour 100 % load

(4) Determination of voltage and frequency regulations under following load changes :

(a) No load to 110 % load in steps not exceeding 25%

(b) 100 % load to no load in a single step . (5) Operation of all protection circuits by simulation.

(6) Operation of UPS fed loads on normal and generator supply (after installation at site and commissioning).

5.0 Fuel System

Fuel tank with capacity suitable for 24 hours 100% operation shall be made of stainless steel sheets and fuel pipework shall be with MS pipes and fittings.

The tank shall be supplied and installed, fully piped up, to provide the service requirements of the genset and as shown on drawings The tank shall be complete with filler cap, contents gauge, overflow pipe, vent pipe and sludge valve. The fuel tank shall be filled as required for testing and commissioning and shall be full at the time of handing over.

6.0 Sound insulation of the room and Vibration Criteria

The contractor shall provide sound level data of the proposed equipment for review of the Engineer. The noise level outside the genset room shall not exceed 75 dBA at 3 meters. Attenuators shall be provided for radiator discharge and air intake. The air intake requirements shall be coordinated at site.

The generator base mounted springs shall be able to absorb 95% of the Engine vibrations. Any louvers provided in generator room shall be of the acoustic type.

7.0 Exhaust

All exhaust gases shall be suitably piped outside the genset room . The engine shall be efficiently, silenced and be complete with a silencer and all fixings to attach the silencer to the generator room ceiling. In addition to erecting the silencer the Contractor shall also be responsible for providing and erecting the fittings necessary to carry the tail pipe through the generator room wall. All fixings shall be anti-vibration type where required and galvanized. Exhaust pipes of the proper diameter, properly insulated with 50 thk rockwool insulation and clad with 22G aluminum sheet, shall be supplied and installed.

They shall run from the exhaust silencers to the outside . The exhaust pipes shall terminate with an adequate bend or cap to prevent ingress of rain.

The total exhaust noise attenuation shall be to 25dBA.