-1- G/TBT/N/THA/319  
Explanatory Memorandum  
Draft ministerial regulation  on high efficiency coil ballasts  
for fluorescent lamps  
B.E. …  
-------------------  
Principle  
Definitions of high efficiency coil ballasts for  fluorescent lamps  
Rationale  
It is hereby deeme d appropriate and necessary  to define  a coil ballast that has an 
energy consumption value no t more than as specified in this ministerial regulation  as a high 
efficiency coil ballast for  a fluorescent lamp . The purpose of th is regulation  is to conserve  
energy and to promote the us e of energy -efficient  materials . This will provide  manufacturers 
and sellers of such product s with  the right to support and assistance from the Energy 
Conservation Promotion Fund. It will  encourage the  manufactur e and sale of this t ype of 
ballast. C onsumers will be able to use energy economically and efficiently, and  will have the 
option to use high efficien cy coil ballast s. This will promot e the country’s energy consumption 
efficiency and reduc e pollution.  
 -2- DRAFT  
Ministerial Regul ation  
Definiti ons of high efficien cy coil ballasts for  fluorescent lamps  
B.E….  
-----------------------------------  
In accordance with S ection 6, Clause 2 and Section 23, Clause  1(2) and Clause 3 of 
the Energy Conservation  Promotion Act, B.E. 2535, with amendments made to the Energy 
Conservation  Promotion Act  (Issue 2), B.E. 2550  contain ing a number of  provisions related to 
the limitation of private rights and libert y as permitted  in Section 29, together  with Section 33, 
Section 41 and Section 43 of the Cons titution  of the Kingdom of Thailand  – with the guidance  
of the National Energy Policy Committee  – the Minister of Energy  issue s a ministerial 
regulation as follows:  
1. In th is ministerial regulation:  
“Ballast” means  a coil ballast f or a fluorescent lamp wi th a capacity as specified in this 
ministerial regulation.  
“Fluorescent lamp” means a hollow tube fluorescent lamp  either in a linear or circular 
shape that  can be used with a single -phase alternating current of 220 volts,  with a frequency 
of 50 Hertz, excluding  fluorescent lamp s that generate visible off-spectrum light for exit sign s 
and illumination in hazardous  areas.  
"Energy consumption  value” means the total power input of a ballast -lamp circuit  
being tested , after correction  for reference state . 
“Ballast-lamp circuit” means an electric circuit or part of an electric circuit composed 
of a ballast  and lamp, usually as part of  a light fitting.  
“Reference lamp” means a fluorescent lamp selected  for testing. When connected to 
the reference ballast under  specified condition s, the lamp  will have  electrical characteristic s 
similar  to those  specified for the standard of each lamp type according to IEC 60921 or IEC 
60929 or Industrial Standards 1506.  
“Reference ballast” means a special ballast designed to be used  as a standard for the 
ballast being tested , and for selecting  the reference lamp. This reference ballast must have  
the necessary characteristic s including  the required  frequency , a stable ratio of voltage over 
power input,  and must be un affect ed by electr ic current  fluctuation , surround ing temperature 
and magnetic field s in accord ance with  Industrial Standards 2319 or Industrial Standards 
1506 or IEC 60929.  -3-  
2. High efficien cy ballasts must have an energy consumption value no t more than as 
specified in th e ministerial regulation , considering the economic situation , the government ’s 
energy policies, the readiness of ballast manufactur e and sales, as well as support and 
assistance provided to manufacturers and sellers  of ballasts . 
The energy consumption  valu e must be  defined  in respect to the fluorescent lamp 
power specified by the manufacturers as follows:  
Fluorescent lamp  power  
(watt s) Energy consumption value  
(watt s) 
18 (linear shape ) 22.5 – 20.0  
32 (circular shape ) 36.5 – 34.0  
36 (linear shape ) 39.5 – 38.0 
 
3. The formula for calculat ing the ballast  energy consumption value  is as follows:  
 
  
 means  the energy consumption value which  is the  total 
power input of the ballast -lamp circuit  being tested , 
after correction for reference s tate. The unit  is the 
watt.  
 
 means  the total power input of a ballast -lamp circuit which  
is connected to the reference lamp and the tested 
ballast. The unit is the watt.  
 where  
 means  the specified electric power or specific power of the 
reference lamp  at high frequenc y, based on  the 
lamp information table. The unit is the watt.  
 -4-  
 means  the electric power of the reference lamp that can 
be measured when connected to the reference 
ballast. The unit is the watt.  
   
 means  the electric power of the reference lamp that can 
be measured when connected to a tested ballast. 
The unit is the watt.  
 
4. The test for determining the energy consumption value of the ballast must be 
carried out by the organi sations specified and announced by the minister.  
5. The standard and met hodology of the test for determining the energy consumption 
value of the ballast must comply with the specifi cations  published  by the minister.  
 
Given on:  B.E. … 
 
Minister of Energy