testing commissioning example.3215

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Part 1 - Description of the works

Testing and commissioning

Testing and commissioningGeneral OverviewEach M&E contractor will be responsible for the testing and commissioning of their standalone installations. In some instances one contractor's commencement willbe dependant upon another's completion or partial completion. For instance: All commissioning is going to be dependant upon the provision of the LV electrical power supplies. Temporary supplies can be provided to a certain

extent, which should be viewed as a last resort. The final commissioning of chillers and cooling towers is going to be dependant upon the chilled water flushing. BMS commissioning is partially dependant upon the commissioning of the systemswith which it interfaces. Fire alarm commissioning is partially dependant uponthe commissioning of the systems with which it interfaces.

Incomplete building construction and finishes works can add to commissioning delays: Escape staircases cannot be pressure tested if there are walls and doors mssing. Busbars cannot be energised whilst contractors are still using them as part of their scaffolding arrangements. Generator engines cannot be started up whilst bricklayers are making good around the flue discharges. Final decorations and finishes should be complete where final fix items have to be installed.

It is not the responsibility of the M&E contractors to point out the missing construction items that are likely to affect their commissioning. Due to their failings particular M&E contractors may not be able to meet the programmed commissioning date. So they are hardly likely to present a list of construction items that will delay the commencement of their commissioning in sufficient time for those items to be cleared before a commencement date they know they cannot meet. Itis more than likely that they will drip-feed the reasons why they can't start as asmoke screen for their own failings.

So it is important that meetings are held well in advance of the commissioning commencement date to establish the following: -

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The power on requirements associated with commissioning. The progress of designmatters, particularly regarding software writing. Are all of the control panelsavailable? Are all of the controls available? Are all of the interfaces clearlyestablished? Are the commissioning resources bought at the award stage still available. Are all commissioning method statements in place. There are no misunderstandings regarding responsibilities i.e. who provides the means of high level access. Any items of outstanding builderswork that could effect commissioning.

Throughout the commissioning period the majority of the work is going to have tobe demonstrated to the consultants and the local authority's satisfaction. This can lead to problems regarding attendance when one particular body cancels for some reason. It is important to ensure that this attendance time has been purchased from the contractors.

It is important to ensure that the commissioning periods of all individual M&E trades tie-in to the same dates. However, the overall commissioning period for the electrical

contractor will need to commence before the dates indicated in the other tradescontract programmes. This is because they need to commission their own MV and LVsupplies prior to the LV supplies being available for other trades commissioning. The commissioning power availability dates for each of the main areas need tobe separately identified on the contract programmes. It is important to show the commissioning periods as separate items. For instance Figure 1.7 clearly indicates that the Overall commissioning period is complete by the end of week 45, andthe Integrated System Testing commences on week 46.

Figure 1.7 Typical Contract Programme Commissioning Sequence

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Don't wait until PC for the Operating Manuals (O&M'S), draft copies should be available well in advance.

Integrated System Testing (IST) When the contractors have completed their stand-alone commissioning and the associated interfaces with other trades i.e. the fire alarm and in particular the BMS. They will all to some extent (perhaps only inattendance) partake in the Integrated System Testing (IST). This is where all of the stand-alone commissioned systems work together to perform the functions asdefined in the specifications. This will include: Automatic sequential re-starting of systems by the generator following a power failure. Functionality of allplant in conjunction with the BMS in fully automatic operation. Functionality ofall plant in conjunction with the fire alarm in fully automatic operation.

In order for this to work correctly all installation and commissioning works associated with the IST need to be complete before its commencement. It will be said that the IST can be carried out in one-week, which in theory may be correct; in practice it is best to allow four-weeks.

Black Building Testing At sometime during the IST period the Black Building Tests need to be carried out. These can be done either at the beginning or end of th

e IST period. The timing is usually determined by how well or not so well the IST is performing. The Black Building Tests basically relate to the operation of the electrical changeovers in respect of partial and total power failure scenarios. It will be said that the Black Building Tests can be carried out in two-days,which in theory may be correct; in practice it is best to allow two-weeks.

Individual services testing and commissioning VentilationThe ventilation ductwork testing will be carried out and witnessed by the consultants during the natural progression of the installation works. The testing of ductwork involves air pressurisation for a given period of time. Following the successful testing particular aspects of the ductwork installations regarding supply air require insulating; insulating is also referred to as lagging. The insulation of ductwork should not be carried out until the ductwork has been tested.

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There are occasions where parts of an installation may require sectional testingbefore they are fully complete in order to allow for the commencement of a following trades work. For instance, sectional testing would be necessary for ductwork that was going to be concealed within riser shafts, if it meant that the riser encasement was critical for another facet of the project's commencement. Sectional testing would also be necessary for all M&E services installed above a none-accessible ceiling in a lobby or reception area, if the ceilings had to commencebefore the M&E services were entirely complete.

The commissioning of a ventilation system should not commence until it has beenthoroughly inspected. The AHU's, ductwork, plenums and attenuators need to be cleared of debris and dust. The commissioning of individual ventilation systems involves: 1. Power on and live cable testing. 2. Ensuring that the fans and controlsoperate correctly when turned on. 3. Ensuring that the BMS control is operational. 4. The total volumes of air movement are in accordance with the specification. 5. The balancing of the air around the system. 6. The fans and controls operate in smoke extract mode with the fire alarm.

Not all ventilation systems will have the full extent of the above six items associated with their commissioning. Some ventilation systems work in conjunction w

ith one-another and could be partially complete for a period of time. It is unlikely that any of the ventilation systems would be commissioned with the BMS in automatic prior to the IST.

Mechanical Mechanical pipework testingThe mechanical pipework testing will be carried out and witnessed by the consultants following sectional completions of the installation. The testing of pipework involves water pressurisation for a given period of time. Following the successful testing particular

aspects of the pipework installations require insulating. The insulation of pipework should not be carried out until the pipework has been tested. There are instances where the pipework will have to be trace heated prior to being lagged. Si

milarly to the ventilation there are going to be instances where sectional testing of pipework is required. The chilled water pipework cannot be tested until itis filled with water, and it should not be filled with water until the entire pipework installation, or large sections of it have been completed. Once the chilled water system pipework has been filled and is undergoing pressure testing, all of the leaking welds and flanged joints should reveal themselves.

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When the leaks have been discovered and rectified the system can be re-filled and retested. (The system may have to be fully drained in order to carry out the repairs). The capability of the mechanical contractor will determine how many times they have to drain and re-fill the system to repair any leaks.

Chilled / condenser water pipework commissioningThe items described below refer also to the commissioning of the condenser waterpipework. The chilled water pipework system is fundamental to the final commissioning of all ventilation systems that require cooling. Therefore any delays tothe chilled water

pipework installation and its subsequent commissioning will extend the IST period and delay the project completion date.

With regard to its commissioning the chilled water pipework system as an entityis probably one of the most difficult to accomplish. Because as stated within the Mechanical Description of Works The chilled water pipework extends throughout almost every area of the building This will include the key areas of the project i.e. basement level plant rooms, risers and levels 17 and 18 plant rooms.

Once the pipework has been fully tested to the approval of the consultants and the commissioning manager then the flushing process can commence.

Flushing involves the pumping of chemically treated water around the pipework. In doing so this treatment removes all of the burrs and debris within the pipework that were created during the welding process. The flushing process will be repeated until the entire residue has been removed from the pipework to the satisfaction of the commissioning manager. A complete description of the chilled watercommissioning process is detailed in template TP01 Chilled Water Plant Room. Thepipework installation is the only part of the chilled water system that gets flushed. The plant items i.e. chillers, AHU's, pumps & fan coil units remain isolated from the system and by-pass valves and spades are inserted ensure that the water flow is maintained throughout the pipework. This means that the residue does

not enter into and clog up the small bore pipework that makes up the internal cooling coils of the plant. Once all of the debris has been flushed out of the pipework the by-pass valves are closed and clean treated water is allowed to flow through all of the coils within the plant.

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The above describes the correct method of carrying out the work. Of course in the real world all manner of shortcuts are utilised to meet the commissioning date. These usually involve the blanking off of pipes in risers that should serve areas where the pipework has not been installed (for whatever reason) prior to thecommissioning commencement date. But being eager not to delay the programmed flushing

commencement, mechanical contractors have been known to commence the flushing ona partly completed pipework installation. Then following its installation the missing pipework is back-flushed using the clean treated water that is flowing around the system. The effects of this can be quite catastrophic, depending upon how much of the systems pipework has been back-flushed, and how much of the residue is blocking the coils of the plant. Unfortunately this may not be known untilparticular plant items fail to accomplish their specified criteria. Then it becomes a case of stripping down each particular plant item and manually cleaning out the coils. It has been known for a manufacturer to spend six-weeks cleaning out their chiller coils as a result of back-flushing incomplete pipework.

Other items to be aware of during the chilled water commissioning process are: Faulty main valves blowing causing flooding to the project Pumps undersized by th

e consultants and requiring replacement Main flow and return pipework connections crossed

There is a lot of work to be accomplished regarding the installation of the chilled water pipework system before the commissioning stage is reached. Also, the programmed installation has to fit within the parameters of the Key Dates and Durations Schedule.

Chillers and cooling towersBoth of the above can be commissioned to a certain extent before they require connection to a fully commissioned condenser water pipework system. The condenserwater pipework will be commissioned in the same manner as the chilled water pipework. The chillers and cooling towers then need to be fully commissioned in orde

r to provide cooling to the ventilation plant via the chilled water system.

Public health Rainwater and foul drainageThe rainwater and foul drainage pipework testing will be carried out and witnessed by the consultants following sectional completions of the installation. The local authority will also

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want to witness these tests once they are fully complete. The rainwater and fouldrainage pipework testing involves water pressurisation for a given period of time. The only commissioning involves the foul drainage sump pumps that are located in the basement level B3 slab.

Instances will arise where bathroom pod wastes are connected to foul drainage riser stacks. Both the pod supplier and the riser installer will be responsible for the testing of their own works. Once the pod has been connected to the riser it will have to be re-tested through the connection and into the riser. This is fine so long as the test holds up. If the test fails then problems will arise because neither the pod supplier nor the riser installer will initially assume responsibility for the leak. This could amount to both companies re-testing their works, and if an innocent party is discovered then they will want compensating fortheir additional work. A project that consisted of a series of high-rise apartment blocks that collectively contained over 500 bathroom pods would warrant a regime that ensured the testing was co-ordinated between all parties. Otherwise there could be serious delays to that project's completion as well extension of timeclaims.

Domestic water supplies

The domestic water supply pipework testing will be carried out and witnessed bythe consultants following sectional completions of the installation. The domestic water supply pipework testing involves water pressurisation for a given periodof time. Following the successful testing the domestic water supply pipework installations require insulating. This should not be carried out until the pipework has been tested. There are instances where the pipework will have to be traceheated prior to being lagged. Domestic water tanks will have to be tested for leakage, booster sets and pumps will have to be commissioned. In toilets, water heaters need commissioning along with

mixing valves and tap pressure and temperature settings. Flood tests need to becarried out and finally the system will have to be chlorinated.

Fire protection Wet risers and sprinklersThe fire protection wet riser and sprinkler pipework testing will be carried outand witnessed by the consultants following sectional completions of the installation. The testing of pipework involves water pressurisation for a given periodof time. Following the successful testing particular aspects of the fire protection pipework installations require insulating. The insulation of pipework shouldnot be carried out until the pipework has been tested.

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Wet riser and sprinkler water tanks will have to be tested for leakage, pumps and controls will have to be commissioned along with fire alarm and BMS interfaces. Flow rates and pump pressures and drain tests have to be carried out. All of which will have to be demonstrated to the local authority.

ElectricalThe termination and testing of an MV cable is a specialist operation that usually occurs at the same time. MV cables are generally energised within 24 hours oftermination and testing. Failure to do so means that the testing should be repeated before the cables are energised. The switching on and off of MV supplies isalso a specialist operation. An MV supply has to be energised in order to createa LV supply. It is possible that the MV supply to a transformer could be energised for a long period of time before the supply is switched through to its LV panel. LV cable terminations are not necessarily a specialist operation, but companies tend to sub-out the termination work along with the pulling-in of the LV (&MV) cables. Before MV / LV supplies are energised the following items need to be completed or in place: Lockable door to the switch room ncoming utility services. Emergency power off buttons installed and working. Metering (if remote from LV panel). Test LV panel with remote power source (flash test) Pressure test (for MV). Earth cable readings. Phase rotation (supply connec

tions must not be crossed). Written power on method statement. Signage on 11,000Volt cables. Advise others of power on date. Provide warning signs and notices.Provide electric shock notice. Provide framed schematic drawing. Provide rubbermats in front of electrical switchgear and switchpanels. Lock off all switcheson MV and LV switchgear and switchpanels.

Electrical commissioning will not be carried out until the majority of a distribution boards sub-circuits or an LV cable installation has been fully terminated.Electrical

commissioning involves testing the cables before they are energised to ensure that there

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are no short-circuits or earth faults. Then following energisation testing to make sure that the circuit will trip in the event of a fault occurring.

Typical electrical commissioning problemsA power-on regime needs to be established by the commissioning manager in orderto focus the electrical contractor and prevent power on delays to critical items.

Single phase 230 Volt supplies for dampers or BMS outstations fed from a local distribution board can give rise to commissioning problems. There could be a situation where power is required to these items but the distribution board has notbeen commissioned. Worse still, it has hundreds of cables hanging out of it thatare awaiting connection. To prevent situations like this arising the commissioning manager needs to establish what items are likely to present commissioning problems and address them accordingly.

Emergency power suppliesEach individual aspect of the emergency power supplies has to be commissioned separately before the generators can be fully commissioned. The ventilation, cooling and fuel oil commissioning will be as explained in the previous ventilation a

nd mechanical paragraphs. So by the time the generators are ready to be fully commissioned they should have: Ventilated plant room Cooling system Completed eust Automatic fuel supply Complete and partially tested electrical mains and controls

The generators will be run-up and commissioned separately before being synchronised and set to work as a group. They will each undergo a load-test for which a separate loadbank will have to be brought in. The controls and remote starting ofthe generators will have to be tested along with the functionality testing of the whole electrical systems; culminating with the Black Building Testing. Each of these steps will have interfaces with the BMS. The most complicated interfacewith the BMS is going to be the load management of the building. This is the

determination and control of the sequential re-switching of the emergency powersupplies to the building following a total power failure.

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BMSIn terms of commissioning everything regarding the BMS is critical. But some things are more critical than others. The most critical items are: Power failure /re-start load management Chilled & condenser water Ventilation

The BMS has input into the majority of the items that make up the IST / Black Building Testing. All of these interfaces have to be proved and demonstrated individually and then globally prior to the IST / Black Building Testing commencement.

In terms of commissioning the BMS has to demonstrate all of the controls / alarms and graphics as identified in the specification, for all associated plant andswitchgear to the consultant's satisfaction.

It is only when the BMS is ready for commissioning that the real problems are about to begin. A typical selection of BMS commissioning problems for a single plant item are listed below. (They usually arrive in this sequence and they commence with the appropriate emotion): -

1. Confusion - with the M&E and fire alarm contractors over who connects to what

with regard to interfaced plant connections. 2. More confusion - with the M&E and fire alarm contractors over who provides what with regard to interfaced plantconnections. 3. Further confusion - regarding exactly what requires power-on for the BMS controls commissioning of a single item of plant. 4. Amazement /slightanger - when it discovered that the criteria finally determined for item 3 wasactually incorrect. 5. Shock / anger - when it is discovered that there are somecritical points that have not been wired. 6. Debate / rage - to determine the blame for item 5. 7. Astonishment - at the discovery that there are not enough pointconnections in the local outstation therefore a further outstation is required. 8. ajor debate / fighting-talk - to determine the blame for item 7. 9. Joy / surprise - the BMS controls did work. 10. Astonishment / fury - following the discovery that the interfaces with the M&E and fire alarm contractors didn't work, usuallydue to the wrong relays being fitted and generally resulting in a small explosi

on.

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11. Bewilderment / time off sick when the software design does not work in relation to the plant and the graphics are displaying something totally different aswell. 12. Satisfaction When it is eventually working correctly. That wasn't too bad! So what if there were a few snags lets move on to the next item, only another109 to go.

There they are, the 12 things needed to know about BMS commissioning. Oh! thereis another. The BMS contractor will not assume responsibility for any of them.

Fire alarmThe commissioning of the fire alarm will revolve around the functionality of itsCause and Effect Schedule. This relates to all scenarios involving evacuation when fire has been detected with various parts of the building. Like the BMS thefire alarm interfaces with other systems. All of which have to be proved and demonstrated individually and then globally prior to the IST / Black Building Testing commencement.

The final software for the annunciator panel cannot be completely written untilthe last detection loop has been completed. This is because the order in which the loops are wired will determine the way the software is written, and it cannot

be commissioned until the software writing is complete.

The fire alarm commissioning involves the activation of each individual detectorand a visual inspection of the annunciator panel display to ensure that they are compatible. The ventilation plant interfaces need to be tested including the smoke extract and staircase pressurisation. All of the ventilation plant should shut down, with the exception of the staircase pressurisation fans, which shouldstart up. There are switches on the annunciator panel that will operate the smoke extract fans at the discretion of the fire marshal or the fire brigade. Otheritems that have to be demonstrated include:

Beam detection Fire telephones Voice alarm sound levels Testing on battery supply only All other plant interfaces Interfaces with the security system Interfaces

with lifts

All of this has to be demonstrated to the consultants and local authority's satisfaction.

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SecurityThe security commissioning involves the setting up and operational testing of all the devices that it consists of. Including the programming of access devices (cards etc.), which enable various modes of restrictive access. The system shouldfail safe (depending upon the area) in the event of power failure or fire detection.

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testing commissioning example.3215

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