electau

If length of stay is intended to be 3 months or less it would be wise to purchase a return ticket to Australia while in Thailand.

As it is only 2 months old you might be able to get the complete unit replaced at no cost, they credit you the amount it cost and then you pay the new amount. You will have a new warranty also. However you may have to take the unit to the dealer who you purchased it from. You will need the invoice for the original purchase.

There is one point to mention on circuit protection and that is protection of consumers mains. In Thailand service protective devices are not generally used. This is generally an HRC fuse. It protects the service conductors, metering and consumers mains against short circuit, provides fault current limiting and provides a point for disconnection of the electrical installation.

They are not installed for overload protection,but will provide protection in certain conditions. Rated current of HRC fuse x 1.6. HRC fuses have a high fault current rating well in excess of the standard MCB.

The functions of the main MCB for the installation is to provide overcurrent protection and short circuit protection on the load side of the device only, it will not protect on the line side. Short circuit currents can be very high.

The minimum size of the main MCB in Thailand is generally 60/63A 10kA (220V) 6kA (380V) as an accepted standard, but often with consumers mains in older installations they may be found to be connected to 4.0sqmm, or 6.0 sqmm conductors.

Final sub circuits have a min of 5kA (220V) 3kA (380V).

Close all windows and door , set thermostat to 25C ( this is the return air temperature). start aircon about 30 minutes before room is to be used. 27C is known as the economy setting, min power consumption. For every degree C below 25 will increase electricity consumption by about 10%, based on a 2400kW (cooling not input kW).

You will not cool your room with the windows open.

Protection against overcurrent.

The term "overcurrent" means both overload current and short circuit current. The danger here is that the temperature rise in the conductors and their insulation will rise to levels at which the effectiveness of the insulation and its expected service life will be reduced.

The operating characteristics of a protective device must satisfy the following.

Ab must be equal to or less than An and equal to or less than Az.

Ab = current which the circuit is designed, eg, max demand.

An = nominal current of the protective device

Az = the continuous current carrying capacity of the conductor.

A2 = the current ensuring effective operation of the protective device and may be taken to for an MCB the conventional time for circuit breakers, 1.45 x An.

A = current in amps.

Example: A 20A MCB as a protective device on a 2.5sqmm circuit. Ab= 20A, An=20A, Az=20A and A2 = 29A.

An MCB will hold 1.2 x An at 40C, but should never be operated for long periods at this rating.

The actual current rating for cables depends on the following. ( single circuit configuration)

1. Method of installation.

Unenclosed in free air

Enclosed in conduit in free air.

Buried direct.

Enclosed in conduit, buried.

2. Ambient temp. This is normally 45C.

3. Type of insulation, PVC insulated and sheathed,75C, XPLE insulated and PVC sheathed 90C. These max operating temperatures must not be exceeded under fault conditions. Note: In Thailand cables are rated at 70C instead of 75C.

4. Voltage drop on the circuit.

The impedance of the circuit protected must be of a value that will trip an MCB in less than 0.4secs in the event of an earth fault. If this can not be achieved an RCD/RCBO must be utilised as the protective device.

I

Try Clipsal ( Thailand) for switch mechs. and plates for series 30 switches. single pole 1- C -2 , the standard switch 10A mech and intermediate mechs, 4 terminal, 1-2, 3-4 and 2-3 and 1-4. 10A.

The 220V control circuit runs to the line side of the MCB to the external control devices then returns to the overload relay control circuit contacts (N/C) then to the contactor coil terminal and then from the other side of the contactor coil to the neutral, N.

A 220V coil will burn out if connected to 380V. A 380V coil connected to 220V will not operate the contactor.

It is assumed that your existing motor for the pump is 3 phase. You propose to use 220V for the control circuit for the external switches to control the operating coil of the contactor. This would be preferred to a 380V control circuit. The external control circuit will require a neutral conductor at the motor starter. All you have to do is replace the 380V coil with a 220V one. The external control circuit will require protection min 10A MCB. The MCB may provide this protection for the cable.

(The single phase connection which will require rewiring of the motor contactor and overload relay to suit 220V connection as the motor current must go through all legs of the relay to prevent tripping on imbalance. It would appear that you are not going to use a single phase 220V motor.)

You will have to allow for voltage drop if the motor is located along way from the main switchboard.

One very good reason for not using a 380V control circuit is that your control devices external to the motor starter may only be rated to 250VAC max.

The control voltage is single phase 220V L and N. the motor voltage is 380V, 3 phases. The control circuit operates the contactor coil only.

Note. Use a 380V contactor coil with a control circuit voltage of 380. use a 220V contactor coil with a control circuit voltage of 220.

With all due respect to electau I would NOT go for the 32A / 4mm² option, stick to 2.5mm² and 20A breakers.

My reasoning? Without UK style fused plugtops the temptation to daisy-chain unfused power boards is just too great. How long will a typical Thai 16A(?) plug and outlet last at 32A (or much more before the 32A breaker opens) before we have conflagration?

It's all well and good when first installed and all the outlets are correctly positioned for the tables, then the management decide to move the tables around and discover there are no longer enough outlets in certain areas......

Good point regarding switched outlets.

Yes one sees your point Crossy, but 4.0sqmm 32 A is permitted for socket outlets. The protective device protects the cable in the event of a fault from undue temp rise. This is permitted under AS3000. Different standards. The flex lead to the appliance should not exceed 1.8metres. Power boards should not be used. One appliance per socket outlet.

Where power boards are used ( and not here) they should be protected by an integral CB not exceeding 10A. Appliances may have an integral fuse or protective device. Leads 2 core + E.

On overload the protective device will trip at 1.45 x rated current. it will hold 1.2 continuously.

Under AS3000 socket outlets, 10, 15, 20A may be protected by a protective device up to 40A and 10sqmm. Different standards. A 10A plug top will fit a 20A outlet, A 20A plug top will not fit a 10A outlet. (AS3112).

You could use 4.0sqmm and 25A protective device.

The Impedance must be low enough to trip the protective device on earth fault, ie 0.4secs. This will be achieved by the use of RCDs/RCBOs.

That is my reasoning, the same problems with power boards will occur with 2.5sqmm and a 20A protective device. 1.45X 20A = 29A convenional tripping time 1 hour at 40C. 1.45x 32= 46.4A. These figures will not cause undue temp rise. The cable temp must not exceed 75C for PVC/PVC.

As one pointed out there are always options, one of the main criteria is cost of cable per metre.

You have a number of options for wiring the hotplates.

1. Wire on 2.5sqmm with a 20A RCBO on each circuit.

2. Wire on 4.0sqmm with a 32A RCBO on each circuit.

Do not exceed the current rating of the protective device.

In calculating max demand allow for aircon load, hot water, other socket outlets etc.

You best option would be 30/100A metering , 3 phase and neutral comsumers mains, load balance over the 3 phases, 50A consumers mains minimum.

You should consult with the PEA/MEA first before commencing any work to obtain their requirements.

As this is a commercial venture your peakload at any time will depend on the number of hotplates is use a guide might be 65% of max demand.

Clipsal (Thailand) have switched outlets.

Consumers mains from the metering point to the main switchboard should be installed in a separate conduit as they are unprotected (no service fuse) and should be PVC insulated/PVC sheathed cables.

Other cables run from the main switchboard ie final subcircuits may be run in a common conduit if required, eg outside lighting and power.

The main switch is a 63A MCB, it would be reccomended that you retain this and install a 63A/30mA RCBO between the load side of the MCB and the line side of the busbar for the final subcircuits. (The size of the consumers mains should be 10sqmm or 16sqmm.)

The 63A MCB determines the max demand of the electrical installation.

The contactor can be wired for a single phase 220 volt motor. The phase (220V) is wired through each leg of the contactor and each leg of the thermal overload relay. the neutral is not switched. The thermal overload relay is matched to the motor current. The contactor coil is replaced by a 220VAC one. The control circuit voltage is 220V.

A 3 phase contactor may be fitted with a 220VAC coil when a 220V control circuit is used, a neutral is required.

380/415VAC control circuits are generally used where the control circuit is contained within the same enclosure, eg the standard motor starter with start/stop-reset buttons.

When the contactor closed, the voltage between phases will be 380V and to earth (or neutral) 220V on both sides of the contactor.

You might be better off using a 3 phase and neutral supply and balance all loading accross the three phases. Will require a 3 phase 32A meter. Mains can be smaller, eg 10sqmm. switch board would have to be upgraded. RCBOs on all socket outlets.

Earthing as required. Installation will most probably be TT, neutral not bonded to main earth.

You will need at least 4 circuits min of 20A 2.5sqmm, you will have to check the size of the consumers mains and metering first.

Allow for any additional load that you may install.

3 phase. A, B, C. 380volts between A to B, B to C, and A to C.

A, B, or C phase to earth E or neutral N is 220V. 380V is 220V x 1,732.

Contactor coil voltage 380V if a neutral is present a 220V can be used.

Earth the computer, it will resolve your problem. Install a RCBO on the power circuit supplying the computer.This will give additional protection against an earth fault.

There are minor leakage currents that are causing the problem.

"In the House of Representatives we get to choose between U.S. lackey party number one and U.S. lackey party number two - between the major parties. So it will be great to 'Assange' the Senate for some Aussie oversight," the mother said.

How true is this statement ? I hope he does get elected. Is given diplomatic immunity, can return home and continue his good work on exposing thise involved in global corruption and government lies.

He will not get diplomatic immunity as he is not employed in the diplomatic service. Also he will not be returning to Australia in the near future and if he ever does it will be well after September 2013.

On all these social networking sites face book, arsebook etc, one should use a false e-mail address

and supply false information so tracking is practically impossible. NEVER give personal information on to these websites. You are responsibe for what you put on the internet

There is enough problems with spam. Accounts may not be able to be deleted along with the information contained within them.

To run for a Senate seat in Australia he has to be resident in Australia. He is not. If he had Australias interests to heart he would not be living overseas in a foreign consulate. When was he last in Australia? When did he last submit a ATO return? When did he last vote in an Australian election?

Range 4500kms it has to be able to fly 9000kms without mid air refuelling, ie it has to fly from here to there and return with max load in kgs. Its average speed is probably around 800km/hour.

A little confused by this post. Range is the maximum distance an aircraft can fly with a single full load of fuel, from take-off to landing.

Mid-air refuelling is irrelevant when talking about an aircraft's range - with ongoing regular mid-air refuelling - any aircraft has an unlimited range.

'here to there and return' is not relevant when talking about range either.

If the range is 4500km, then it should be able to fly 4500km on a single full load of fuel - not 9000km return.

Are you confusing range with combat radius?

In WW2 the range of an aircraft was the max distance it could operate and be able to return to its base. This is why Japan could not be attacked directly from Midway, there were no aircraft with the range required until the B29 which operated from Saipan. After the war the B36 was developed it had a max range of 10000miles. It ws superceded by the B52.

In flight refueling was later developed but it can not be relayed upon so that the aircraft can return to its base, in this case the PRC. An inflight refuelling aircraft would be shot down in a hostile application.

Wiki has it's estimated specs. Range 4500 km

Range 4500kms it has to be able to fly 9000kms without mid air refuelling, ie it has to fly from here to there and return with max load in kgs. Its average speed is probably around 800km/hour.

"China has spent lavishly on its military in recent years as its economy boomed, giving the country the second-largest official defense budget after the United States."

Right.

Military spending as a percentage of GDP, eg, the US financial deficit is 103% of GDP

The Australian Federal Election is on Sat. 14th September 2013. The PM announced on Tuesday.

Assange will not have a hope of obtaining preselection for the Senate. He has to be in Australia. If he was genuine he would face his investigation in Sweden first.

I suspect you are right but I'm intrigued anyway. If nothing else the face plates are much cheaper and look as if they will match the real thing - I've got about 70 to buy shortly so saving a couple of thousand is attractive - it pays for a couple of bathroom sockets with built in RCDs, for example.

Purchase one (1) of them, examine it, check to see if the PVC is brittle it should have a certain amount of impact resistance, the open it up and examine the internal components. After that you will not be able to use this particular fitting. They do seem very low cost.