GPRS- Operation & Maintenance Manual - ESC

A C.J. P.RRev. Prep. Check.

DCC Type of Doc.:

Project:

Title:

Consortium:

Contract Nº

Sub Contractor: Sub-Contractor Document Nº

ATA1691D-0000-G0006

Av Lincoln 4240 (C.P. 1419)Villa Devoto - Buenos Aires

Argentina

Rev.

P/PS-18Q0-00

Page

1 of 25

IBERDROLA BEMCO

Dept: Unid: Version

Document N° 18Q0-7-EKD-GMO-TOR-001 Rev.

A

Index/Rev Engineering Reg. Nº:

Operation & Maintenance Manual

Contents Code:

FUEL GAS TREATMENT SYSTEM

Dept.

FUJAIRAH EXTENSION PLANTScale: - A4

Details of RevisionD.L.

Date Appr.For Information08/04/08

X002678

Aprovado

x000432

For Information

CLIENT: Arabian Bemco JOB: BEMCO Fujairah Rev. A

FUJAIRAH EXTENTION PLANT

Operation and Maintenance Manual

18Q0-7-EKD-GMO-TOR-001

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18Q0-7-EKD-GMO-TOR-001 - Rev A - Operation and Maintenance Manual

OPERATION AND MAINTENANCE MANUAL 1 MANUAL SCOPE .......................................................................................................................... 3 2 SYSTEM – GENERAL DESCRIPTION .............................................................................................. 3 3 OPERATION................................................................................................................................ 5

3.1 ESD Valve........................................................................................................................... 5 3.2 Primary Gas Filter................................................................................................................ 8 3.3 By Pass Skid. .................................................................................................................... 10 3.4 Primary Regulation Skid. .................................................................................................... 10 3.5 Meter Run Primary Skid. .................................................................................................... 12 3.6 Condensate Tank Skid. ...................................................................................................... 14 3.7 Boilers Fuel Gas Skid. ........................................................................................................ 15 3.8 Boilers Skid....................................................................................................................... 16 3.9 Cyclonic Gas Filter ............................................................................................................. 18 3.10 Secondary regulation Skid.................................................................................................. 20 3.11 Main PLC Control of the Gas Station.................................................................................... 22 3.12 Maintenance of the PLC’s and Visual Panels......................................................................... 24 3.13 Instruments Maintenance................................................................................................... 24





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1 MANUAL SCOPE

The scope of this Manual covers the Operation and Maintenance of the FUJAIRAH EXTENTION PLANT. Its objective is to describe the system plant from the general point of view as well as from the details of operation and maintenance of all equipment and their associated control instrumentation. The main goal is to describe de Operation and Control of the Gas Treatment Station.

2 SYSTEM – GENERAL DESCRIPTION

The System as a whole contains a Main PLC (Programmable Logic Control) Control of the Gas Station installed inside the Control Room of the Plant. All related electrical signals (monitoring and active controls) converge to this Main PLC Control. A visual Display Panel allows accessing all Station sections and visualizing all parameters and their values in a very easy manner. Alteration and correction of these parameters can also be achieved; more over, commands can be generated to modify statuses or behaviors, depending on needs.

Also, the Main PLC Control communicates with the DCS PLANT CONTROL SYSTEM through a serial path, allowing the Gas Treatment Plant to be and integrated part of the whole System. In addition, an Instromet FC2000 flow Computer is installed with the Main PLC Control, to provide for corrections of gas volume and flow consumption by the Heaters and by the Turbine Generators. Measuring Devices used for consumption of Turbine Generators are “Custody Transfer” approved, complying also with AGA7 and API21.1 Standards for Historic Flow Record Storage. The Main PLC Gas Station Control architecture contains two CPUs and Power supplies in a redundant fashion to insure a continuous running. There also contains a slot fit with an Ethernet Communications Module which allows communication through a TCP/IP protocol with external devices, i.e. PC’s, Laptop, etc.





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Station Control Panel





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3 OPERATION

3.1 ESD Valve.

3.1.1 General Description. The ESD Valve is composed by an actuator that is associated to a ball valve. Its main task is to interrupt completely the Gas Flow to the Station in case of an emergency or a special event that justifies this action.

3.1.2 Associated Instrumentation.

3.1.2.1 MAIN FEATURES APERTURE MANUAL COMMAND AUTOMATIC BLOCKAGE BY REMOTE SIGNAL SENSING AUTOMATIC BLOCKAGE BY LOW PRESSURE DETECTION MANUAL OR AUTOMATIC EMERGENCY SHUT DOWN DOBLE EFFECT TYPE ACTUATOR SUPPORTED Please refer to document 18Q0-7-EKD-MIP-TOR-001 - ACTUATOR CONTROL PANEL

3.1.2.2 SUPPLY PRESSURE • Pressure regulating valve type 1301G (Pos 4) lowers the feeding pressure to the pneumatic circuit down to 30 Kg/cm2. • Pressure regulating valve type 1301F (Pos 6) lowers the value of the pressure on the first stage to a nominal value of 7 Kg/cm2. • The Relief Valve (Pos 8) alleviates the overpressure to its set value of 11 Kg/cm2.

3.1.2.3 OPENING MANUAL OPERATION • Manual Opening of the ball ESD valve can be accomplished only by turning locally the ESD Manual Command Lever (Pos 9).

3.1.2.4 CLOSURE BY REMOTE SIGNAL OPERATION • Remote closure of the ball valve ESD is produced by de-energizing the solenoid valve in Pos 11.

3.1.2.5 MANUAL EMERGENCY CLOSURE (SHUT DOWN) OPERATION





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• This manual ESD operation is accomplished by pressing the pneumatic local push button located in the control panel.

3.1.2.6 GAS ACCUMULATOR TANK The Gas Accumulator Tank (Pos 23) was built according to ASME Sec. VIII Standards, and it is designed to ensure operation up to two complete runs in case of an emergency

3.1.3 Operation during start-up. The proceedings for Start-Up are as follows:

a) Verify that the ESD Valve is in the “CLOSED” position. b) Verify that all associated manifolds are with the purge input closed or sealed. c) Verify that the “Close command” on the Main PLC control or the Emergency Shut-down push button is not activated. If any of them is active, opening of the ESD VALVE will not be possible. d) Verify that the Gas input pressure to the Station is within the allowed range and tolerance of the pressure gages and pressure transmitters. e) Verify that the valve ACTUATOR is in the “Local” command position to allow us to open the valve. Verify also that the “Reset” button is not pressed. f) With all previously mentioned verifications performed, one can continue with the Valve Opening procedure by opening of the By-Pass of the valve and thus starting to fill up the piping of the Gas Station. g) Once the pressures are equalized one can safely proceed to finally OPEN the ESD VALVE. h) As soon as normal operation is achieved, be sure to close the By-Pass valves.

3.1.4 Operation during normal functioning of the plant. During normal functioning of the Plant, the ESD valve is in its Open normal state of operation. It shall remain Open unless any of the abnormal conditions occur, such as an emergency shut-down or a shut-down command has been taken place which caused the closure of the ESD Valve. In any of these cases, to resume the normal Open condition the following procedure must be followed:

a) Verify and correct the possible causes of closure of the ESD Valve (Gas input pressure, emergency button, security conditions, etc.) b) Upon verification and repair of the above mentioned causes, proceed to RESET all closure commands, either pneumatic or electric from the Main PLC Control of the Station.





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c) Once this is done, proceed to equalize pressures downstream by the By-Pass valves, place the command in the “LOCAL” position and proceed to open the ESD Valve.

d) As soon as normal operation is achieved, be sure to close the By-Pass valves.

3.1.5 Emergency STOP. If an Emergency Shut-down has occurred, all causes of possible malfunction (input pressure, emergency button, security conditions, etc.) must be verified, identified and corrected prior to re-opening of the ESD Valve.

Do not proceed to re-opening of the ESD valve in any case, unless the cause of the shut-down has been perfectly identified and corrected.

Once the above conditions have been met, opening procedure of the ESD valve is as follows:

a) RESET all closure commands, either pneumatic or electric from the Main PLC Control of the Station.

b) Once this is done, proceed to equalize pressures downstream by the By-Pass valves, place the command in the “LOCAL” position and proceed to open the ESD Valve.

c) As soon as normal operation is achieved, be sure to close the By-Pass valves.





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3.2 Primary Gas Filter.

3.2.1 General Description. Primary Filter Skid is a coalescent filter type containing input and output valves and a maintenance by-pass.

3.2.2 Associated Instrumentation. Associated instruments are:

• A Differential Pressure Transmitter to determine the presence of a filter obstruction due to accumulation of dust or particles. This transmitter would send a pre-alarm or a full-alarm to the operator in case of a high differential pressure value.

• A pressure indicator to show pressurization level as an aid during maintenance procedures.





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3.2.3 Operation at start-up. During start-up be sure of:

a) Verify that Input and Output valves are in their CLOSED position. b) Verify that all manifolds are with their purge inlet closed or with the cup on and sealed. c) Pressurize both filter branches through the By-Pass of each of the Input valves d) Pressurize the filter through the filter By-Pass.

3.2.4 Operation during normal functioning of the plant.

During normal functioning of the plant, one of the filters would be active and the other one would be standing-by. In case of maintenance, cartridge replacement or any other cause, proceed to enable the stand-by line and pass the other branch to stand by. Reversed procedure must be followed to put the filter back in operation.





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3.3 By-Pass Skid.

3.3.1 General Description.

The regulating by-pass allows passing directly the inlet pressure to the station, without pass through the regulating stage, in case of low inlet pressure.

3.3.2 Associated Instrumentation. Instrumentation associated with By-pass skid are: pressure transmitter for by-pass inlet pressure metering, a lineal electrical motorized valve. Downstream of this valve is a safety slam-shut type pneumatic valve. In the same branch are three outlet pressure transmitters.

3.3.3 Operation during normal functioning of the plant.

The By-pass operates in case of the inlet pressure is below a pre-defined value, before that the auto regulated pneumatic regulation train leave to regulate the outlet pressure. The safety pneumatic valve will remain constantly open and only will act in case of high regulated pressure. The by-pass start to act when inlet pressure is lower than minimum pressure before regulating stage, which is received through a pressure transmitter located in the by-pass entrance. When the minimum predefined value is reached, the motorized valve start to open slowly as a function of an increasing ramp like signal defined in the control system. In this way, inlet pressure of the station will pass to the outlet directly. On the opposite case, when the inlet pressure starts to increase and a maximum value of pre-defined pressure is reached, the control system stats to close the valve with a predefined ramp and the pneumatic regulating train will operate. If motorized valve fail, transmitters located downstream of safety pneumatic valve, will receive high regulated pressure and the system will send a command in order to close the valve. 3.4 Primary Regulation Skid.

3.4.1 General Description. The Primary Regulation Skid is composed of two regulation branches with their corresponding manual Input and Output Valves. Each branch is made of a Blocking Valve, a Monitor Regulating Valve and an Active Regulating Valve. The Blocking Valve is a safety one to block passage of the gas in case of a high pressure detection at the output. The Monitor Regulating Valve is a “Fail to Close” and the Active Regulating Valve is a “Fail to Open type” These valves are of the pneumatically operated auto regulating type. In case of have an input pressure drop below the minimum established, the By-Pass branch line will be activated as describe in the following paragraph 3.3.





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3.4.2 Associated Instrumentation. The associated instrumentation for each one of the skid branches are run limit switches mounted on the blocking and monitoring valves which indicate the limit position of each valve. There is also a gas input temperature transmitter, a regulated gas pressure transmitter and an output temperature transmitter for each branch. In the output collector of this skid there is a temperature transmitter common to the two branches.

3.4.3 Operation at start-up. During start-up:

a) Verify that Input and Output valves are in the CLOSED position. b) Verify that all manifolds are with the purge input closed or with the cup on and sealed. c) Pressurize the line through the by-pass of the Input Valve; once this is done, open the Input Valve and activate the special purpose blocking valve button. d) Similar procedure must be performed with the Monitoring and Regulating valves so the whole branch line becomes totally pressurized and regulated at the desired pre-set value.

3.4.4 Operation during normal functioning of the plant. This skid main task is to regulate the pressure to the Turbine Generators. This is accomplished through the Regulating Valve which adjusts the pressure to the pre-set value locally entered to the pilot. The regulating valve is of the Fail to Open and the monitoring valve is of the Fail to Close type. Branch regulation functioning is as follows: Primarily, the Regulating Valve is the one in charge of regulating the output pressure by sensing the down stream pressure fed back by a pneumatic connection. In case of a fault, this valve goes to the OPEN position, producing a rise in the output pressure up to the preset regulated value in the Monitoring valve; at this instant, the Monitoring valve takes over and starts to regulate the output pressure. In case of Monitoring Valve failure, it goes to the CLOSED position thus causing the stand-by branch starting to regulate the output pressure. The function of the Blocking Valve is to sense the output pressure and block the output of the branch as a safety measure. Once the stand-by branch starts to operate, since it is identical to the other branch, operates in exactly the same way. Upon any of the branches failure, maintenance work is mandatory to repair and leave the “off line” branch in perfect conditions, standing-by and ready to go. The Temperature Transmitter on the output of each regulating branch senses the gas temperature and feeds it back to control the Three-way Valves placed before the Heat Exchangers that heat the gas entering regulation, in order to keep it the temperature at the preset value. Those heat exchangers are placed before the Primary Regulating Skid.





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At the output collector of the skid there is a gas Temperature Transmitter which, in case of a temperature drop below the pre-set limit, sends an alarm signal to the Main Control to take action.

3.5 Meter Run Primary Skid.

3.5.1 General Description. Gas Metering Skid includes an inlet manual valve and an outlet valve, a by-pass for maintenance of the meter and components associated with metering process. The flow meter is ultrasonic type and it is mounted with its corresponding pressure and temperature transmitters for correction of the consumption gas volume.


Instrumentation associated with this skid is: an ultrasonic meter, a transmitter of static pressure and a temperature transmitter.





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3.5.3 Operation at start-up. Before pressurizing the metering branch line, it must be verify that inlet and outlet valves are closed. It must be also verified that all manifolds are closed too. Then proceed to pressurize the metering branch line and then the main by-pass branch line. Finally proceed to open the outlet valve of the metering branch line, verifying downstream of this connection, the availability of the equipments connected to this skid. Next proceed closing the by-pass inlet valve, leaving it operative if need be.

3.5.4 Operation during normal functioning of the plant. The metering branch line will remained seal and operative all the time. Only will be necessary to take part in, for meter maintenance or contrast. In this case, proceed as follows: opening of the by-pass outlet manual valve and then the inlet one. Next close the regulating branch line outlet valve and then the inlet one, isolating in this way the meter and leaving the gas flow passing through the by-pass. Depressurize then the metering section for its later maintenance intervention.





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3.6 Condensate Tank Skid.

3.6.1 General Description. The condensate tank accumulates the condensate of liquids coming from coalescent filters and cyclonic filter.

3.6.2 Associated Instrumentation. Instrumentation associated with this tank is a floating level that shows when the tank must be emptied.





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3.6.3 Operation during start-up. Only must consider that tank discharge valves must be closed while start-up.

3.6.4 Operation during normal functioning of the plant. The objective of Condensate Tank is to store liquids accumulated in the filters. Level indicator will send an alarm signal to the local HMI indicating high level. In this moment, will be necessary to empty the condensate tank.

3.7 Boilers Fuel Gas Skid.

3.7.1 General Description.

Fuel gas system to boilers is divided in two parts: one of pressure regulation and the other one for flow metering. The first one has two regulating branch lines with manual inlet and outlet valves. Each branch line has a regulating valve with block incorporated. The block has a position indicator that indicates to the control system when the block was activated. These valves are auto-regulating type, operated pneumatically. In the regulating outlet of each branch has a pressure indicator that shows the regulated pressure.

The second one, metering stage, has a turbine meter with its pressure and temperature transmitters, for flow metering correction. It also has a by-pass for intervention task to the meter, in fail case or maintenance.


Instrumentation associated with each regulating branch is composed of: pressure indicators of block valves, regulating pressure transmitters, a meter turbine type for metering, a temperature transmitter and a pressure transmitter for correction of the consumption gas volume.

3.7.3 Operation at start-up. Inlet and outlet valves must be closed during start-up. Verify that all manifolds have purge closed or with the bonnet covered. Pressurize the branch line through the inlet valve and active the block valve button (included with this purpose): the branch remains totally pressurized in the regulated pressure.

Proceed to pressurize the metering branch and then the main by-pass branch line. Finally proceed to open the outlet valve of the metering line. Next close the by-pass inlet valve, leaving it operative if need be.

3.7.4 Operation during normal functioning of the plant. The objective of this skid is to regulate the outlet pressure and to measure the corrected gas volume to the boilers. It is reached through a regulating valve that adjust the pressure according to the value pre-defined locally in the pilot. This valve integrates regulation and the block in case of regulating valve fail.





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The regulating branch line works as follows: the regulator valve will regulate the outlet pressure, through a pneumatic connection downstream of it for outlet pressure metering. In case of fail this valve will go to open position making the valve block act, and producing the reserved branch start to operate. Because of its identical construction, the other branch line works in the same way. When one branch fails is mandatory to start with maintenance tasks, in order to leave it operative and in reservation, in case of operation line fail.

The metering branch line will be operative all the time. Only will be necessary an intervention in case of meter maintenance or contrast. In this case, proceed as follows: opening of the by-pass outlet manual valve and then the inlet one. Next close the regulating branch line outlet valve and then the inlet one, isolating in this way the meter and leaving the gas flow passing through the by-pass. Depressurize then the metering section for its later maintenance intervention.

3.8 Boilers Skid

3.8.1 General Description. The Boilers Skid is made of two Boilers dedicated to heat up the water for the Heat Exchangers located in the Primary Regulating Skid and Secondary Regulating Skid.





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The Heat Exchangers rise the gas temperature prior to the pressure regulation to avoid freezing due to the loss of pressure. There are two pumps to re-circulate the water and Three-way Valves to keep the constant temperature of the Heat Exchangers These re-circulating pumps are manually operated from the HMI in the MCC (Motor Control Center)

3.8.2 Associated Instrumentation. The associated instrumentation to this skid are local Pressure Indicators and local Thermometers for the operator’s visual indication.

3.8.3 Operation during start-up: At start-up the following procedure must be followed:

a) Proceed to fill-up completely the water circuit through the special purpose quick connector. b) Once all air is eliminated from the water circuit, proceed to energize one of the water pumps, starting to re-circulate the water and verifying that no air is present in the circuit. Stop the pumps. c) After the previous steps are done and verified, proceed to start each one of the boilers by first gas pressurizing the corresponding gas Burner. Gas leakage must be verified and if there is none, proceed to energize the local installed Flame Control. d) Proceed to initiate the flame ignition by pressing the local START button. The burner controller will start and supervise the burner flame. e) Set the control temperature at a pre-established value to keep the water temperature constant. f) Proceed to start the re-circulating pumps and the equipment will be in full normal operation.

3.8.4 Operation during normal functioning. Under normal plant operation, the skid functions automatically. The boiler flame would be modulated as a function of the desired pre-set temperature. In case that one of the boilers fails, it must be put “out of service” for maintenance. Meantime, proceed to start the stand-by boiler. Regarding the re-circulating water pumps, there would always be one operative and the other one at stand-by. If the operative pump fails at any time, proceed to start the previously standing-by and stop the faulty one. Perform the maintenance works and leave the other pump in stand-by until needed.





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3.9 Cyclonic Gas Filter

3.9.1 General Description The Cyclonic Gas Filter skid is in charge of filtering the gas before entering the Gas Compressor.

3.9.2 Associated Instrumentation. The Cyclonic Filter instrumentation are: Input and Output Valves, a By-Pass line for the filter maintenance and a differential Pressure Transmitter. It also has a motorized valve to the Compressor by-pass.

3.9.3 Operation al start-up. During start-up:





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a) Verify that input and output valves are CLOSED and that all manifolds are with the purge closed or with the cups on and sealed. b) Be sure that the down stream Compressor is in proper conditions to receive the output gas of the filter. c) Proceed to pressurize the skid through the by-pass valve then open the input and output valves so it will become totally pressurized.

3.9.4 Operation during functioning of the plant. During the normal functioning of the plant, the Filter would be normally operative. In case of required maintenance, proceed to enable the By-Pass line. The reverse procedure shall apply to reentering the filter to its normal functioning conditions. The motorized valve would be operated from the HMI by the operator at his will.





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3.10 Secondary regulation Skid

3.10.1 General Description. The Secondary Regulation Skid is made of two regulation branches with their corresponding input and output valves of the manual type. Each branch has its own valve, acting as an integrated regulating, monitoring and blocking valve. The blocking function has a position indicator that sends an alarm signal to the control system when is activated. These valves are of the auto regulating and pneumatically actuated type.

3.10.2 Associated Instrumentation. Each of the branches is equipped with a run limit switch mounted in the blocking valve, an input Temperature Transmitter and a regulated Pressure Transmitter.

3.10.3 Operation at start-up. To Start-Up, verify that:

a) Input and Output Valves are in the CLOSED position. b) All manifolds have their purge inputs closed or with the cups on and sealed. c) Proceed to pressurize the line through the input valve and once this is done, proceed to activate the special pressurization button of the Valve. d) With the first branch already pressurized, proceed to pressurize the second branch performing the same steps as before. e) Next, proceed to open the output valves so the skid will go to the operative state.

3.10.4 Operation during normal functioning of the plant. The main task of this Skid is to regulate the pressure of the gas entering the Gas Compressor. This is accomplished through the Regulating Valve which keeps the output pressure within the locally set- point on the pilot. This valve is of the Fail to Open type and has a blocking function in case of an output pressure overrun. The regulating branch is as follows: The regulating valve regulates the output pressure sensing the existing pressure down stream through a pneumatic connection.





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In case of a fault, this valve will go to the Open position, then the blocking actuates, causing this faulty branch to go out of service, in which case the other non-faulty branch takes over regulating the output pressure. It is mandatory that if a malfunction occurs in one of the branches, maintenance must begin immediately in order to repair the “out of service” branch in order to leave it in standby and ready to act in case of failure of the operating branch. The Temperature Transmitter at each regulating branch senses the output temperature and feeds it back to the three-way valve control placed up-stream before the Heaters, thus keeping the constant the input gas temperature to the Secondary Regulating skid. There is also a Pressure Transmitter to sense the regulated output pressure of the skid.





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3.11 Main PLC Control of the Gas Station.

3.11.1 Components Description.

The MAIN PLC CONTROL of the Gas Station consists of two Central Processing Units (CPUs) working in a redundant fashion. This means that if one of them fails, the other takes immediate control with no loose of data nor control over the Gas Plant. Two redundant Power Supplies are connected in a similar way to insure continuous operation of the MAIN PLC CONTROL. There are thermal circuit breakers and fuses mounted in the Main PLC Control Cabinet panel, one for each electrical section. Inputs and Outputs of the equipment are distributed in two equal redundant islands. In case of a failure, control of the plant passes to the second branch so the flow of gas to the Turbine generators would not be affected. Over the left cabinet door an “emergency fist-stike type push button” and the flow computer in charge of processing the ultrasonic flow meter data (flow, temperature, pressure) to compute the Gas flow and volume of the Fuel consumption. Interior illumination is provided by means of two fluorescent tubes and door switches for automatically turning on/off. Mounted on the cabinet there is an industrial type TCP/IP SWITCH to allow connection of PC’s, Laptops, etc. Over the right hand door of the Cabinet there is a touch sensitive visual panel screen for the local operation and visualization of data (see details in the next paragraph)

3.11.2 Control Visual Panel. Characteristics of the Visual Panel mounted in the front of the Cabinet are as follows: Magelis XBTGT 5330 (Touch-sensitive screen)





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ELECTRICAL CHARACTERISTICS Power supply Voltage 24 VDC Limits 19.2…28.8 VDC Voltage cut < 10 ms Inrush current < 30 A Consumption 28 W

1) A touch-sensitive graphical display screen (color STN 10.4” or color TFT 10.4”, depending on model). 2) A multicolor light (green, orange and red) indicating the status of terminal.





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1) A screw removable terminal block for 24 VDC power supply. 2) A slot for Compact Flash card, with cover. 3) An input/output terminal block (1) for loudspeaker connection, one input (reset), 3 outputs (alarm, buzzer, run). 4) An extension unit interface for future use. 5) An RJ45 type connector for Ethernet TCP/IP link (10BASE-T/100BASE-TX) with an activity LED. 6) Two A type USB host connectors for external devices and application transfer connection. 7) An RJ45 type connector for RS 485 serial link (COM2) with a switch selector for polarization of serial link COM2, used in Modbus. 8) A 9-way male SUB-D connector for RS 232C or RS 422/485 serial link to PLCs (COM1).

3.12 Maintenance of the PLC’s and Visual Panels.

3.12.1 PLC´s. PLC’s do not require any preventive maintenance. Corrective maintenance can be accomplished only with highly trained personnel and sophisticated Laboratory instrumentation. In case of failure of any PLC component, I/O modules, communication modules or peripheral modules, direct replacement of the fault component is highly recommended. In the analog input signals, a verification of accuracy can be performed once every two years and proceed to repair or replace the faulty device which is causing the deviation from normal. Again, this verification would also need trained personnel and Laboratory instrumentation.

3.13 Instruments Maintenance.

3.13.1 Pressure Transmitters and Differential pressure Transmitters. A testing by comparison is recommended to be performed every six (6) months. Re-calibration can be done every two (2) years. On critical parameters transmitters, a special attention should be paid if they are disconnected from the equipment, performing a current override in those applicable cases.





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3.13.2 Temperature Transmitters.

A testing by comparison is recommended to be performed every eight (8) months and a re-calibration every three (3) years. On critical parameters transmitters, a special attention should be paid if they are disconnected from the equipment, performing a current override in those applicable cases.

3.13.3 Static and Differential Pressure gauges. A settings re-calibration every one (1) year is advisable. On Pressure Gauges over critical parameter a special attention should be paid in case they are disconnected from the equipment, performing a contact override if necessary.

3.13.4 Instrument’s Brands and Models. The following list shows the Brands and Models of the provided Instrumentation:

INSTRUMENT Brand Model Pressure Transmitters, Static YOKOGAWA EJA530 Pressure Transmitters, differential YOKOGAWA EJA110 Temperature Transmitters YOKOGAWA YTA110 Pressure Indicators WEISZ 4100 Thermometers WEISZ 1060 Pressure Gauges, differential WEISZ BR791-F Limit switches for valves DDeI SMA-500-1 Level switches W.E.Anderson L6EPS-S-S-3-O

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