Testing Of Electrical Installations In Thailand

[david96]

All electrical installations must be safe from fire and shock as far as practicable.

Information based on AS3000 and AS3017.

Testing ( Verification ) of Electrical Installations

SAFETY. Isolate supply to installation at Main Switch.

Test before you touch. All MCBs in off position.

1 Disconnect main neutral conductor at main neutral link.

2 Disconnect MEN link between the main neutral link and earth link.

3 Earthing Tests.

3.1 Test continuity of main earthing conductor to the ME electrode (max 0.5 ohms.)

min size 4 sq mm.

3.2 Test equipotential bonding from the main earth electrode to all exposed metal

work that may be connected to earth. (max 0.5 ohms.)

3.3 Test all PE conductors from the earth link (bar) to the earthing points of all

light fittings, socket outlets, and permanently connected equipment.

(In practice this should not exceed 0.5 ohms)

4 Insulation Tests.

4.1 Test voltage 500VDC, 250VDC if electronic equipment or equipment has EMC or

SPDs installed or disconnect these devices before commencing tests.

4.2 Test between main neutral link and earth bar minimum 1.0M (ohms)

Test between main neutral link and final subcircuit actives min 1.0M (ohms)

Test between each active and the earth bar min 1.0M (ohms)

In practice all tests should be over 50M (ohms)

5 Polarity Tests.

5.1 Use a trailing lead and continuity tester. Connect one end of the lead to the

active of the circuit at the switchboard an the other with the continuity tester

to the active terminal of all switches, socket outlets and permanently connected

equipment. Do each circuit in turn. Switches must operate in the active

conductors.

After completing these tests make sure all conductors that have been

disconnected are reconnected with the exception of the main neutral.

5.2 Reconnect the MEN link.

5.3 Before connecting the main neutral carry out a polarity test.

Observe safety procedures.

5.4 Reconnect supply and test with a voltage indicating device.

Readings must be A-E supply volts, A to N supply volts, N to E 0 volts.

5.5 Disconnect supply and reconnect main neutral conductor to main neutral

link.

6 Supply can now be reinstated. Turn on main switch.

Switch on each circuit in turn and check operation of all lights and permanent

equipment. Check supply to all socket outlets and recheck polarity with

suitable test equipment. Verify that RCDs are tested using the intregral test

button. If you have not got suitable equipment to carry out a current test

at 30ma, a 15watt test lamp with leads connected A to E will trip a RCD when

connected to a socket outlet.

Notes. Sheathed elements have an allowable insulation resistance of

10000 ohms. Other electrical equipment may be subject to other standards.

Information contained in this article should be useful as a guide for the safe

practical electrical testing of electrical installations in Thailand.

If the installation has direct earthing (TT) a MEN link will not be installed.

On a TT system there may be a voltage above 1 volt between A and E,

depending on how far the installation is from the distribution transformer

This is normal.

Test Equipment.

Voltage indicating device, neon test lamps or digital multimeter.

Voltstick proximity voltage detector.

Insulation tester 250/500 volt with continuity range 0 to 3 ohms.

A long trailing lead 2.5 sqmm flexible.

Clips and probes.

All instruments to be checked for operation before use. Zero the resistance

on the instrument when using the trailing lead.

[Crossy]

Excellent stuff David, not too technical

If I may I'd like to add this to the wiring web page, there for eternity when this topic drops off page one

Edited June 1, 2008 by Crossy

[skipvice]

Thanks David, I will add it to my Thai Electrical files for future reference.

[david96]

Excellent stuff David, not too technical

If I may I'd like to add this to the wiring web page, there for eternity when this topic drops off page one

Thanks for the compliment Crossy, It might be useful to some if we had a Thai translation also.

[elkangorito]

http://www.thaivisa.com/forum/index.php?s=...t&p=1962265

[Valjean]

Excellent stuff David, not too technical

If I may I'd like to add this to the wiring web page, there for eternity when this topic drops off page one

Thanks for the compliment Crossy, It might be useful to some if we had a Thai translation also.

I've got a certified Thai-English translator on my team and could ask him to do this. I've been thinking about a glossary also of key terms - ones that our Thai mates might not know or could get confused on; ground, line, conduit, etc. Is this doc ready for translation? Would people want more added to it. If I have him do the work it would be good to have one well vetted and edited doc.

I was thinking of this in particular of having this in almost a checklist format that anyone could hand to the Thai electrician handyman and have him confirm all the steps. Perhaps almost in a "Testing Of Electrical Installations In Thailand for Dummies" type format.

Happy to put some work into this and get it done as a thanks for all the help I get here it people want that.

[david96]

Excellent stuff David, not too technical

If I may I'd like to add this to the wiring web page, there for eternity when this topic drops off page one

Thanks for the compliment Crossy, It might be useful to some if we had a Thai translation also.

I've got a certified Thai-English translator on my team and could ask him to do this. I've been thinking about a glossary also of key terms - ones that our Thai mates might not know or could get confused on; ground, line, conduit, etc. Is this doc ready for translation? Would people want more added to it. If I have him do the work it would be good to have one well vetted and edited doc.

I was thinking of this in particular of having this in almost a checklist format that anyone could hand to the Thai electrician handyman and have him confirm all the steps. Perhaps almost in a "Testing Of Electrical Installations In Thailand for Dummies" type format.

Happy to put some work into this and get it done as a thanks for all the help I get here it people want that.

A direct translation to Thai and proof read is all that is required. Items 1 to 6 can be incorporated in a work method statement and test results recorded if desired. It should then be signed and dated by the competent person (electrician) carrying out the work. (Legally responsibility falls on the person who connects the installation to the source of supply.)

I can supply an explanation of terms used. Disclaimer: The original author of this information is not responsible for any alterations, additions or translation errors in the article that may be misleading or encourage unsafe electrical work practices.

Edited June 16, 2008 by david96

[david96]

Excellent stuff David, not too technical

If I may I'd like to add this to the wiring web page, there for eternity when this topic drops off page one

Thanks for the compliment Crossy, It might be useful to some if we had a Thai translation also.

I've got a certified Thai-English translator on my team and could ask him to do this. I've been thinking about a glossary also of key terms - ones that our Thai mates might not know or could get confused on; ground, line, conduit, etc. Is this doc ready for translation? Would people want more added to it. If I have him do the work it would be good to have one well vetted and edited doc.

I was thinking of this in particular of having this in almost a checklist format that anyone could hand to the Thai electrician handyman and have him confirm all the steps. Perhaps almost in a "Testing Of Electrical Installations In Thailand for Dummies" type format.

Happy to put some work into this and get it done as a thanks for all the help I get here it people want that.

A direct translation to Thai and proof read is all that is required. Items 1 to 6 can be incorporated in a work method statement and test results recorded if desired. It should then be signed and dated by the competent person (electrician) carrying out the work. (Legally responsibility falls on the person who connects the installation to the source of supply.)

I can supply an explanation of terms used. Disclaimer: The original author of this information is not responsible for any alterations, additions or translation errors in the article that may be misleading or encourage unsafe electrical work practices.

Glossary of Electrical terms used in the article "Testing ( Verification) of Electrical Installations".

A Active, phase or line conductor.

N Neutral conductor.

E Earth conductor or ground conductor.(US)

PE Protective earth, the earth conductor protecting a final subcircuit.

MEN Multiple Earth Neutral .

EMC Electro Magnetic Compatiblity

SPD Surge protection device.

TT Direct earthing system (no MEN link)

MCB Circuit Breaker.

RCD Residual Current Device (in the US they are known as GFCIs.)

RCBO Residual Current Device with Overload protection. (combination MCB/RCD)

ME Main Earth electrode and main earth conductor from earth bar. min 12.7mm / 4 sq mm.

M ohm 1000000 ohms

Edited June 17, 2008 by david96

[ianlty]

Hi Guys,

I stumbled on this thread while searching for High Voltage Test in Thailand.

Do you guys know where can I test Basic Insulation Level Tests in BKK?

Im looking at DRY/WET impulse,switching and power frequency test up to 1050kV.

Cheers

[InterestedObserver]

Hi Guys,

I stumbled on this thread while searching for High Voltage Test in Thailand.

Do you guys know where can I test Basic Insulation Level Tests in BKK?

Im looking at DRY/WET impulse,switching and power frequency test up to 1050kV.

Cheers

Is that 1050kV spec a mistake, that's some serious voltage.