david96

The most accurate information is from the Foreign Affairs of the Embassies, in this case NZ.

One of the duties of Foreign Affairs to monitor political developments in foreign countries.

They are the most accurate assessments of the current situation, not the opinions of "journalists" and video footage which is out of date in many cases.

The most accurate information is by direct radio link from the "front line" and this is very difficult to obtain.

They are warnings only for their own citizens.

On the 1900hrs ABC-TV news 17/05/2010 The Foreign Affairs Minister advised Australians not to travel to Thailand unless it was absolutely essential. The telephone number for consular services at the Embassy was also given along with the Canberra (ACT) number.

He also stated that the Embassy would be closed indefinately.

Each pump motors should be conected to an RCBO and be earthed. All external lights should be connected to an RCBO and be earthed. If an earth conductor cannot be run an electrode minimum 1.2M X 12mm copper clad steel can be installed at each light fitting and pump motor. Bond with 4sqmm minimum earthing conductor.

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Thanks, as I said that the pumps were in the fish pond, this implied that they are submersibles. Does this make any difference please? The feed is direct from the DBd mcb, via the usual Thai insulation taped joint which is external to the pond. However I have purchased an earth rod..about two metres long and a plastic terminal box and will install both.

There are about thirty lights involved, some high in the air and others built into posts. It’s just not possible to pull an earth cable between the ‘built in post ones’, nor is it really practicable to sink an earth rod at each post. Would just a GFI unit in the DBd suffice please. I think that long term the lights need changing

Thanks also to everyone who has given advice/information.

If it is not practicable to install an earthing conductor (2.5sqmm) and not practicable to install an earth electrode

install a RCBO (MCB/RCD) unit rated at 30mA on the distribution board as the very minimum requirement.

Consideration should be given in the future to upgrade the electrical installation where required.

A 4 port hub should do the job for you. Splitters are ideal if one wants to run 2 telephones or fax machines over a 4 pair Ethernet cable.

In Thailand one drives on the left hand side, vehicles are right hand drive.

When walking keep to the right eg, on footpaths, marked areas for pedestrians, foot bridges. This seems to be the norm from observation.

Let DIAC know that you will be travelling out of Australia and if it is before you enter the second stage of processing for the 100 visa they will enter this information into their database, DIAC need to know your current address and telephone number so they can contact you. If you are expecting your 100 visa (applicant) it may be prudent not to travel until it is received.

RJ45 4 pair cable. 10Base-T and 100Base-T

Pin number

1 data tx

2 data tx

3 data rx

4 not connected

5 not connected

6 data rx

7 not connected

8 not connected

Pins 4 and 5 blue and blue/white pair is reserved for voice and fax services.

So you can have a splitter for data and telephone services or 2 data using pairs 4/5 and 3/6.

one splitter at each end.

With 100Base-T4 uses all 4 pairs for data.

Latest information here, Australian Embassy closed until further notice. Monday 17/05/2010.

http://www.smartraveller.gov.au/zw-cgi/view/Advice/Thailand

You could install a digital or analogue DIN rail mounted timer (analogue are easier to programme) they have switched contact rated at 10A resistive. You use this to switch a contactor and install a control switch (auto-off-manual). The timer has as switch which can be used to test or manually overide the timer.

Each pump motors should be conected to an RCBO and be earthed. All external lights should be connected to an RCBO and be earthed. If an earth conductor cannot be run an electrode minimum 1.2M X 12mm copper clad steel can be installed at each light fitting and pump motor. Bond with 4sqmm minimum earthing conductor.

However, if the pumps are double insulated ( international IEC marking) they do not require earthing but the socket outlets supplying them do.

Thank you Oh Great America. What would we do without your guidance?

Every time your ass is in the vise you come running and begging to us Yanks.

With out us you be speaking German right now

And you did not join in until Dec 1941 when the Japs attacked Pearl Harbour.

Mr Winston Churchill was very happy. You also made a lot of money out of it.

Has anyone had any experience with evaporative airconditioning, manufacturers claim their units for a house will bring the ambient temperature down to 27C.

Naam might have some experience here.

Ref to post #136.

You can purchase a 24 module polycarbonate surface mounted enclosure with DIN rail with neutral and earth bars.

You then install 2 or more 4 pole RCCDs and protect them on the line side with MCBs. 2 RCCDs will cover 6 final sub circuits.

Alternatively you can install 1 x 2 pole RCBO for each circuit that has socket outlets connected. Eg. 6 RCBOs

You still use the 63A MCB as the main switch.

David,

your QLD-Aussie assumptions do NOT apply to Thailand and neither do your cited building restrictions. there is no need to suspend a cassette type indoor unit with threaded downrods. in single story homes the metal frame (to which the gypsum ceiling is fixed) is suspended with several steel bands per m² from the roof steel structure or in case of double story homes the frame is fixed to the concrete ceiling. this frame can hold without problems and without any additional securing one or several cassette units.

You are refering to the standard T -bar ceiling with modular tiles 600x600mm and 1200x600mm the framework which is suspended by single 6mm wire hangers. generally at 2metre intervals.

There are limitations on what a T -bar ceiling will support. What is the average weight of these units in Kgs?

Some may be confused with the definitions of some electrical terms. Here are some.

Main switchboard (MSB). The switchboard that controls the electrical installation, the consumers mains terminate at a main switch.

Main switch. The switch controlling the electrical installation at the main switchboard. The main switch may be a MCB.

Sub board / distribution switchboard (DSB). A switchboard which controls part of an electrical installation, it is supplied by sub mains from another switch board, generally the main switchboard.

Consumers unit (CU) is a UK term for sub board.

Loadcentre is another term for a distribution switchboard.

Final subcircuit. A circuit that has a protective device and that does not supply a sub board

eg lighting and power circuits are final subcircuits.

RCD is any residual current device. (The generic term is "Safety Switch").

RCCD is a residual current circuit breaker. operates only on residual current. (earth leakage)

RCBO is a device that combines the functions of an MCB and a RCD. (Residual Current Breaker Overload) a 63A MCB with a 30mA RCD is an RCBO.

Protective device, can be a Fuse, MCB, RCCD or RCBO. any device that provides electrical protection, eg SPD is a surge protection device.

The cassette type would have to be installed between the ceiling joists and also be suspended from the roof trusses by threaded downrods to take the weight of the fan coil unit. A T -bar ceiling with removable tiles would make it easier. Other wise the ceiling would have to be cut to size depending if it was plasterboard or gyproc (trade name)

A lot would depend on how much ceiling space is available, most houses in the tropics with a gable roof have very limited space, as this wasted space anyway.

This would apply to existing houses, on new construction allowance can be made in the design.

From a cost perspective the wall mounted split system is the way to go.

One very good reason for NOT using a RCBO (in this case 63A/30ma) as a main switch is if you have an earth fault on one circuit you will lose all power to your installation, lights, power etc.

That i a good reason, but the only saftey problem I see with that is if I trip in the dark going to reset the switch.

Schneider electrics Square D catalogue shows two set ups with a SPD.

1) MCB mainbreaker, SPD and then MCB and RCBO breakers

2) RCD mainbreakerm SPD and only MCBs.

Everything properly grounded.

If I am having problems , can I not shut down all breakers and turn them on one by one to find out where the problem is?

Is it then possible to switch out the breaker or el.appliance that is giving me the problem?

This is the lowest cost option, the one you have decided on and it will give you the level of protection that you require.

One very good reason for NOT using a RCBO (in this case 63A/30ma) as a main switch is if you have an earth fault on one circuit you will lose all power to your installation, lights, power etc.

With RCDs unwarranted or nuisance tripping is just the device doing its job, and you may have this problem if one has excessive standing leakage currents. This is not a fault and the problem is resolved by installing 2 or more RCDs. The standing leakage current is reduced on each circuit.

Electronic equipment, surge protected power boards, equipment with capacitors connected to earth for EMC

etc have higher values of standing leakage current. The problem is minimal in the average residential electrical installation.

With reference to post #53 by Naam.

"In excess of 75C" This is the ambient air temperature?

This would exceed the ratings for most cables. This temperature is above the recomended for a storage HWS. No person could work in that temperature.

I thing you will find that 50C to 55C perhaps 60C at a max. Cable and protection devices working at those ambient temperatures would require them to be operated at derated values.

Normal ambient temperature is normally 40C or 45C when installing electrical equipment and most airconditioning calculations are based on a max of 45C with a return air temperature of 22 to 25C at the fan coil unit in a residential installation. (Guide only)

oz/british paranoia at its best (as so often)

An isolating device may be a protective device on the final subcircuit (MCB) but for maintainance and safety a switch should be installed adjacent to the unit, in this case to control the compressor unit and the fan coil unit. If the location of the switch is exposed to the weather a weatherproof switch must be used.

An isolating device by definition can be a switch, MCB, RCD or RCBO.

If you have to keep resetting an RCD you will either have a problem with nuisance tripping or you have a faulty item of electrical equipment.

With nuisance tripping the standing earth leakage current should not exceed 30% of the RCD rating in mA. For a 30ma RCD this would be 10mA. In practice in an individual residential electrical installation this is a minimal problem.

SPDs should have a minimum rating of 40kA , 8/25 microsec, 275V. protected by a MCB and connected on the load side of the main switch. This will be close to the main earthing bar at the main switchboard. DIN rail mounting SPDs have replaceable plug -in modules.

Sensitive electronic equipment may have additional protection by means of surge and spike protected power boards at the socket outlets.

You are more likely to experience the effects of an indirect lightning strike than that of a direct one on an electrical installation or the effects of HV switching on the distribution network.

You should also consider where the first socket outlet for your telephone service is to be located, this should be a RJ12 or RJ45 mounted on a flush mounting plate. You should have a twin socket outlet located adjacent, about 150mm from the telephone outlet.

The location of all switches and socket outlets should be accessible at all times and not blocked by furniture or fixtures.

Thanks for the comments, but as for safety you do not see a problem with my set up for now? The SPD is what Square D recommends and yes, placed right after the main breaker. The telephone line is going approx. where you say but it will be awhile before that is in place.

No, not with safety. the SPD should be protected with a MCB and the earth from the SPD should be run to the main earth bar, minimum 4sqmm.

Can you please explain why it is unsafe? Are you then saying that if I have a RCD mainbreaker I can not have a SPD?

An RCD/RCBO is a residual current device, 30mA.

An SPD is a surge protection device to protect from spikes, surges etc exceeding 275V. they must be protected by a MCB generally 32A. DIN rail mounting units have replaceable modules and are changed when the indicator changes from green to red.

SPDs are connected on the load side of the main switch.

They are two completely different devices.

The RCDs are for safety. You are using the RCBO as a main switch in this instance.

1. Aesthetically a cassette type AC would be better as I would have to have 2 wall mounted units only 3m apart from each other due to column and door restrictions and they would be installed low on the wall (~2.1m height) due to a beam.

<snip>

3. for heating the lower the better. for airconditioning 2.1m is perfect. you don't want to disturb the warm air in the upper area of the room. that's where some inefficiency of a ceiling mounted unit comes in cooling mode. a ceiling unit for heating mode is in my [not so] humble view a worst case scenario!

I think the underside of the wall mounted units will be installed at a height of around 2.4m with a ceiling height of 2.7m.

Obviously the cassette will be at 2.7m.

Surface mounted on the ceiling, not flush mounted? they would have to be mounted on the ceiling joists with pipework and electrical cabling in the ceiling.

Overload protection should be part of your airconditioners controls.It will probly be self resetting (auto reset).

The MCB on the final sub circuit protects the cable from short circuit and any additional load eg socket outlets that may be connected.

One thinks that the reason for fitting the National MCBs is that they are low cost and the only product readily available. They are very common in Thailand.

why would anybody install additional switches for ACs? they all come with remotes.

Compliance with AS3000/2007.

The switch is installed for isolation purposes adjacent to the equipment.

But we're not in Oz

That said, a number of countries require local isolation of A/C units (Malaysia, Italy, Philippines that I know from experience), Thailand does not.

A question for our OP. Are you sure they're just switches? I've seen several installations with local MCBs for A/C when there was insufficient room in the distribution board, simply replacing these with switches could remove your overload protection!!

Thailand in general uses a National 2 pole MCB 1.5kA of suitable current rating mounted in a National surface mounted block. You never rely on a remote for electrical isolation. The final subcircuit should be protected at the switchboard with a MCB.

David, I remember that ducted A/C systems are also quite popular in Australia and several of my former neighbours in Sydney had ducted systems installed in their homes.

Also, correct me if I am wrong, I have read somewhere that new domestic A/C installations in Australia must be inverter systems or fitted with soft starters.

Ducted units were installed in residential installations in the 1980s with a central compressor unit fan unit. they were not very energy efficient.

The policy now is to install inverter type split systems with the fancoil unit mounted on the wall.

Run them as you need them.