What a Solar ACDB Is, and What We Build

The AC distribution board takes the inverter's AC output and distributes it — to the plant loads, the metering point and the grid interface — with feeder protection, surge protection and safe isolation. It is the board the DISCOM inspector looks at, the board the net meter hangs off, and the point where the solar plant meets the rest of the electrical installation.

Wisdom Techno Solutions builds solar ACDBs at our Vadodara works in 1.6 mm or 2 mm CRCA sheet steel, powder coated, or in transparent polycarbonate IP65 enclosures for small rooftop systems. Boards are built for indoor or outdoor mounting with IP52, IP65 or IP67 protection as the location demands, wall, floor or stand mounted, with switchgear conforming to IEC 60947 and IS 8623.

  • MCCB / MCB per feeder, rated to the inverter output and the load schedule
  • AC surge protection device (Type II) protecting the distribution point
  • Metering and net-metering provisions to the DISCOM's connection specification
  • Isolation for safe maintenance of the plant-side and grid-side circuits
  • Ferruled, labelled wiring to the approved drawing
  • IEC 61439-1 assembly practice and MNRE guidelines

AC Distribution Board Technical Specifications

The table below is the standard build. Feeder count, breaker ratings, metering and enclosure execution are set from the inverter schedule, the DISCOM specification and the site.

ParameterSpecification
Board type ACDB — AC distribution board, distributing solar inverter output to loads, metering and the grid interface
Position in the plant After the inverter (or after the AC combiner box in multi-inverter plants)
Phases Three-phase and single-phase inverter outputs, per the inverter schedule
Feeder protection MCCBs, MCBs and fuses per feeder, rated to the inverter output and load schedule
Surge protection AC surge protection device (Type II), coordinated with the plant lightning-protection design
Metering Energy metering and net-metering provisions per the DISCOM connection specification
Rated voltage up to 690 V AC; 800 V class available — see the 800V LT Panel
Enclosure 1.6 mm or 2 mm CRCA sheet steel, powder coated; transparent polycarbonate IP65 for small rooftop boards
Ingress protection IP52 indoor; IP65 and IP67 options for outdoor installation
Mounting Wall, floor or stand mounted, indoor or outdoor
Component standards IEC 60947 and IS 8623 compliant switchgear; enclosure ingress per IEC 60529
Assembly practice IEC 61439-1 practice and MNRE guidelines for solar installations
Testing Routine tests and inspection at the works before dispatch, with test report
Facility Kotambi, Vadodara, Gujarat, India
Delivery 6 to 7 weeks from drawing approval, subject to switchgear availability

Where the ACDB Sits — and What Feeds It

In a single-inverter plant the inverter output lands directly in the ACDB. In multi-inverter plants an AC combiner box first collects the inverter outputs close to the inverters, and one protected feeder runs to the ACDB. Upstream of the inverter sit the DC boards — AJB and DCDB — described with the whole chain on the solar BOS electrical package page. For 800 V AC high-voltage inverter fleets, the distribution point is built as an 800V LT panel.

What to Send for an ACDB Quotation

The inverter schedule (models, count, output rating, phases), the feeder arrangement to loads and grid, the DISCOM connection specification including metering and net-metering requirements, indoor or outdoor mounting with the IP rating, and the site single line diagram. With these five the board is engineered without assumptions.

Common Mistakes in ACDB Specifications

  • Metering provisions left to "as required" — the DISCOM's connection specification decides the meter chamber, CT class and isolation arrangement; get it in writing before the enclosure is sized
  • Breakers rated to the inverter frame, not its actual maximum output current
  • SPD treated as optional — the ACDB is the plant's AC surge collection point
  • IP rating chosen by habit — an outdoor ACDB needs IP65 minimum and a canopy
  • No spare ways — plants get extended; two spare feeders cost little at build time

How Wisdom Techno Solutions Builds AC Distribution Boards

An ACDB is an LT panel and is built like one: busbar and feeder sizing with thermal margin, clearances per LT practice, IEC 61439-1 assembly discipline, GA and SLD drawings submitted for approval before manufacturing, routine tests and inspection before dispatch, and the test report shipped with the board. The same works builds the rest of the solar package, so the boards arrive matched in enclosure practice and labelling.

Related Technical Guides

Related Panel Types

If this is not the right fit for your layout, these are the related products we build to the same standard:

Send Your Single Line Diagram

Email your single line diagram, load list and system fault level and our engineers will come back with a technical offer. Not sure what to send? See what a panel manufacturer needs in order to quote accurately.

Manufacturer Wisdom Techno Solutions
Works Plot 9, Nilkanth Industrial Park 1, near Kotambi Stadium, Kamrol, Kotambi, Vadodara, Gujarat 391510, India
Email connect@wisdomtechnosolutions.com
Phone +91 80002 29727
Working hours Monday to Saturday, 8:00 am to 5:00 pm IST
Delivery lead time 6 to 7 weeks from drawing approval, subject to switchgear availability

Frequently Asked Questions About AC Distribution Boards

What is an ACDB in a solar system?
The AC distribution board — it takes the AC output of the solar inverter and distributes it to loads, metering and the grid interface, with an MCCB or MCB per feeder, an AC surge protection device and isolation for maintenance. It is the point where the solar plant meets the rest of the installation.
What is the difference between an ACDB and a DCDB?
Which side of the inverter they are on. The DCDB is before the inverter, working with DC at the string system voltage; the ACDB is after the inverter, distributing three-phase or single-phase AC. The protection devices differ because DC arcs behave differently from AC arcs, so the boards are not interchangeable.
Does the ACDB handle net metering?
Yes — the ACDB is normally where net-metering provisions live: the meter chamber, CT provisions and the isolation arrangement the DISCOM requires. Send the DISCOM connection specification with the enquiry and the board is built to it.
What enclosure options are available?
Powder-coated CRCA sheet steel in 1.6 mm or 2 mm, wall, floor or stand mounted — or a transparent polycarbonate IP65 enclosure for small rooftop boards where the meter must stay visible. Ingress protection from IP52 indoor to IP65/IP67 outdoor.
What protects the ACDB against surges?
An AC surge protection device, typically Type II, coordinated with the plant lightning-protection design. Long AC runs from roof-mounted inverters pick up induced surges, so the SPD is a primary component of the board, not an accessory.
Can you build 800 V AC distribution boards?
Yes — for high-voltage inverter fleets the distribution point is built as an 800 V class LT panel with appropriately rated switchgear. See the 800V LT Panel page.
Which standards apply to an ACDB?
Switchgear conforms to IEC 60947 and IS 8623, enclosure ingress protection per IEC 60529, and the assembly follows IEC 61439-1 practice and MNRE guidelines for solar installations.
What do you test before dispatch?
Routine tests and inspection at the works: insulation resistance, wiring verification against the approved drawing, torque checks, functional operation of breakers and SPD indication, and IP hardware checks. The test report ships with the board.
What should I send to get a quotation?
The inverter schedule, the feeder arrangement, the DISCOM connection specification with metering requirements, indoor or outdoor mounting with IP rating, and the site single line diagram — through the Get a Quote form.

Page updated: 17 September 2026