MDB main distribution boards for factories & buildings
The MDB is the heart of every factory's electrical system. We design and build MDBs that handle today's load, leave room to grow, and run safely.
The main distribution board takes power from the transformer and feeds every sub-board in the plant. A good design has to account for current ratings, short-circuit levels, busbar layout and spare capacity for future expansion.
We handle the whole job: load calculation, single-line diagram, fabrication in our own workshop, transport, installation and connection to the transformer on site. The system is tested before it is energised.
The main distribution board is where the whole plant's power comes together, so a problem there affects the entire production line, not one machine. Planning an MDB replacement should therefore start with measuring the real load, not simply matching the old board — most plants have added or changed a great deal of machinery since the original board was installed.
Always allow room for future circuits. Providing spare ways and busbar capacity at the design stage costs far less than extending or replacing the board again when the plant expands a few years later.
MDB work we do
- MDBs for new factories
- MDB replacement & upgrades
- MDBs with energy metering
- Sub-distribution boards per production line
- Electrical room relocation
We serve plants in Saraburi, Ayutthaya, Pathum Thani, Bangkok, Samut Prakan, Chonburi and Rayong. See our service areas
MDB Main Distribution Boards
Load & short-circuit calculation
Main breaker, busbar and protection ratings matched to your transformer and real loads.
Designed for expansion
Spare space and circuits for the machines you'll add later.
Metering
Power meters so you can track your plant's energy use.
Built & tested in our workshop
Assembled and inspected before it goes to site, which means less downtime during installation.
Installation & transformer connection
Our crew installs the board, runs the main cables and connects to the transformer.
Supervised by licensed engineers
Designed and checked by a licensed professional power engineer.
Signs your MDB needs inspection or replacement
The board is decades old
Protective devices and insulation have a service life; as they age, risk increases quietly.
Total load is close to the main breaker rating
Once added machinery pushes load to the rating, there is no safety margin left for peaks.
No spare ways for new circuits
Adding circuits to a full board causes heat build-up and unsafe terminations.
Breaker spares are hard to find
An obsolete main breaker turns every repair into a long outage.
Thermal scans show hot spots
Hot spots on busbars or terminals are an early warning that should be acted on immediately.
No energy metering in the board
Without metering you cannot see where consumption is rising or plan to reduce it.
What to prepare before requesting an MDB quotation
- Transformer size (kVA) and the current main breaker rating
- Historical maximum demand or recent electricity bills, if available
- The existing single line diagram, or photos inside the board
- Number of outgoing circuits needed, plus spares for the future
- Electrical room dimensions, installation position and access route
- When the plant can shut down and the supply can be switched off
A clear process, from site survey to handover
- 01
Consultation & site survey
We review your requirements, electrical loads, installation space and existing systems.
- 02
Engineering & quotation
Our engineers prepare the single-line diagram, select the right components and give you a clear quotation.
- 03
Fabrication & assembly
Panels are built in our own workshop by experienced technicians, to the approved design.
- 04
Testing before delivery
Every panel is inspected and function-tested before it leaves our workshop.
- 05
Installation & support
On-site installation, commissioning, handover and ongoing technical support.
Real work from real sites
Frequently asked questions
What is the difference between an MDB and a DB?
The MDB is the main board fed from the transformer and supplies the whole plant. A DB is a sub-board fed from the MDB that supplies a specific area or machine.
What size MDB do I need?
It depends on your transformer size and total load. Our engineers calculate it from your machine list and expansion plans.
Can you replace an old or overloaded MDB?
Yes. We survey the existing system, plan the changeover to minimise production downtime, then install and test the new board.
How long will the power be off during an MDB replacement?
It depends on the scope and site conditions. Work like this is normally planned for a weekend or a scheduled shutdown. Our team surveys the site and proposes a work plan, including the outage window, for your approval before starting.
What is the difference between an MDB and a DB?
The MDB is the main board that receives power from the transformer and distributes it to sub-boards; a DB is a distribution board feeding loads in one area. Our knowledge article on MDB panels explains this in more detail.
Does the work require coordination with the utility?
If the scope involves changing the meter or transformer size, coordination with the local electricity authority is usually required. Tell us the scope early so the sequence and paperwork can be planned.
Planning an electrical or control panel project?
Send us your drawings or project details. Our engineers will review them and come back with recommendations and a quotation.