Maximum Demand Calculation For Hua Hin House

[stgrhe]

Let me ask it this way. How many wires do you run from the meter to the DP? 3 or 4 ? Thanks

I suppose it will be one cable with four cores PVC insulated and single or double sheeted like e.g. Thai-Tazaki's cable type NYY-GRD, MEA TYPE C-GRD or similar power cable.

THIS SPECIFIC CABLE'S SPECIFICATION

NUMBER OF CORE : 2 - 4 cores plus earth

CONDUCTOR : Solid and stranded annealed copper, sizes 1 mm2 up to 300 mm2; Earth conductor size 1 mm2 up 35 mm2

INSULATION : PVC

COLOUR :

- 2 cores – Light gray and Black

- 3 cores – Light gray, Black and Red

- 4 cores – Light gray, Black, Red and Blue

- Earthing core - Green/Yellow

SHEATH : PVC

UNDER SHEATH Color: Black

CLASSIFICATION : Maximum conductor temperature 70 °C Circuit voltage not exceeding 750 V

TESTING VOLTAGE : 2,500 V

http://www.thaiyazaki-electricwire.co.th/index_power.html

[stgrhe]

The exercise with the MDC is now almost done and I like to express my thank to all Thai Visa members who have contributed and especially I like to thank Elkangorito and David96 who both have provided advice by PM. I am ever so grateful, many thanks.

The next step will be to select the consumer unit and its equipment. I a looking at two solutions, 1) to go for a more industrial type cabinet and fit the units on DIN-rails linked together with bush-bars; or 2) go for the more common cabinet type.

The advantage with special designed cabinet is that it will allow me to fit other units I need in the same cabinet, but I suppose it will be a more costly alternative. I will chose the equipment from ABB's product ranges.

[David006]

Just a thought..have you checked with your friendly power company as to the availability of the required service.

I just paid to have our meter changed to permanent from temp building and asked for 30amp.. "No Can".. "only have 15amp here..most people have 5amps" ...sigh! I wrote down potential load of about 16AMPs...to no avail....TIT ( I guess 5A is enough for a big screen TV, fridge and a fluorescent strip or two).

Oh ...and the site inspection consisted of holding a clipboard staring at the house, glancing at the domestic box and asking if we had a ground rod..lol

Okay sorry... just read you are in a development etc. with three phase ..disregard

Edited December 17, 2009 by David006

[powderpuff]

If you are willing to pay (I guess around 8000 baht) I'll bet you can get 15/45 amp meter. Go back to PEA office & ask them again. Speak to the manager if necessary.

[stgrhe]

If you are willing to pay (I guess around 8000 baht) I'll bet you can get 15/45 amp meter. Go back to PEA office & ask them again. Speak to the manager if necessary.

The meter will be a 30/100 amp meter for 3-phase so there is no need to pay any money. The developer has already paid for the transformer and it will be installed before the end of the month. The poles and the insulators are already there.

[david96]

The method I used to come to a figure of 25mm squared copper cable for the Consumer Mains was derived from AS3008. AS3000 gives a very conservative figure (very safe) whilst AS3008 provides a safe but more cost effective cable sizing calculation.

If you want to make sure that everything is ok, go with 35mm squared copper cable. It is more than ample for your situation (buried in conduit). I recently did the same calc for zapatero.

What value of MD in amps per phase and route length in meters did you use on the heaviest loaded phase?

[stgrhe]

The method I used to come to a figure of 25mm squared copper cable for the Consumer Mains was derived from AS3008. AS3000 gives a very conservative figure (very safe) whilst AS3008 provides a safe but more cost effective cable sizing calculation.

If you want to make sure that everything is ok, go with 35mm squared copper cable. It is more than ample for your situation (buried in conduit). I recently did the same calc for zapatero.

What value of MD in amps per phase and route length in meters did you use on the heaviest loaded phase?

David,

Elkangorito has informed me that he will now focus on another forum, the Generator Solution Forum, so you may not get a reply on here to your post.

G.

[stgrhe]

This is the final result of this exercise, which was started in order to establish the maximum demand, and balancing of the load over the three phases, for our Hua Hin villa that is currently under construction. As earlier said a combined input from Elkangorito and David96 has been used to arrive at the figures below.

My apology for the poor resolution.

MDC - Page 1

MDC - Page 2

Load Balance - Page 1

Load Balance - Page 2

Load Balance - Page 3

[stgrhe]

The second MDC page has been updated.

[stgrhe]

Just an update on this project. The design of the distribution board has now been set and the unit ordered on PMK Industry in Nonthaburi for production. PMK is ABB's main distributor in Thailand and I found this company very prompt and skillful for a Thai company.

The DB will comprise two section of which one has the form of a standard layout for RCBO fittings, the right section of the cabinet drawing below, while the left section is specially designed.  

The standard right section will hold 33 ABB DS271 type RCBO with three sockets in spare for eventual future expansion. The left specially designed compartment will hold the main incoming terminals, the main circuit breaker (ABB MCCB type T2max), surge arrestor, a panel volt meter, a panel ampmeter plus selector switches and fuses.

Photos will be posted once the unit has been designed and put into operation.

Layout drawing

Electrical drawing of the specially designed left compartment

Distribution board configuration.

[stgrhe]

Yesterday I went up to PMK in Nonthaburi, the manufacturer of the distribution board, to fetch the distribution board. It consists of one cabinet with dimensions 120 x 100 x 20 cm (w x h x d) with two separate compartments.  

The left compartment holds the terminals for the incoming mains, the main circuit breaker, a surge arrester with HRC fuses, neutral and earth bars, current transformers and shortening links for an ammeter, and fuses for a volt meter. Both meters are panel mounted with individual selector switches.

Each phase current can thus be measured whereas the voltage can measure each phase to neutral and each phase to another phase. PMK also fitted three panel mounted indicator LEDs, one for each phase.

The right side compartment hoses 33 RCBOs, one for each circuit with three slots in spare for future expansions.

The products are:

1. MCCB - ABB T1maxB160 16kA

2. Distribution Board - ABB 3-phase, 4-wire, 36 CCT, main lug, bushbar 200A

3. RCBOs - ABB DS271 1P, 30mA

3.1 1 x 32A

3.2 11 x 25A

3.3 10 x 20A

3.3 11 x 16A

4. Control Fuse - ABB E931-32 with fuse base rail mounting

5. HRC Fuse Link - ABB 125A, size 00

6. HRC Fuse Base - ABB OFAX 00 P3, 3-pole, 160A, size 00

7. Voltmeter - Crompton E244-02V, 0 - 500V, scale 90 degree, class 1.5

8. Ammeter - Crompton E244-022A, 0 - 50A, scale 90 degree, class 1.5

9. Current Transformer - Crompton CI-MSQ-30, 50/5A, burden 3VA, class 3

10. Volt Selector Switch - Salzer SA16-7-3, 7 positions, 16A, 660V

11. Amp Selector Switch - Salzer SA16-4-3, 4 positions, 16A, 660V (O = off will not be used)

12. Surge Arrester Class II - DEHN 952310, DG M TT 275 40kA (8/20)

13. Shortening Links 

Separately supplied:

14. Surge Arrester for Satellite TV Antenna - DEHNgat 909705, DGA GFF TV 2.5kV (10/350)

15. Surge Arrester for Telephone Line - DEHN Blitzductor, BXT ML4 B 180 10kA (10/350) + BXT BAS

Distribution Board front view

Left side compartment

Left side compartment close up

Right side compartment holding the RCBOs

[david96]

A very well designed Main Switchboard and of a high standard of workmanship by the contractor.

[stgrhe]

A very well designed Main Switchboard and of a high standard of workmanship by the contractor.

Thank you David!

I am very pleased with PMK's work and it was surprisingly cheap too. The total price including VAT came to 137,000 baht only.