Mechanical services / New Zealand

Mechanical services
switchboards.

Power and control for the plant behind your building.

CWS designs and manufactures mechanical services switchboards (MSSBs) for HVAC, pumping, ventilation and refrigeration. Built in Invercargill for projects throughout New Zealand, with power circuits, motor control and BMS interfaces coordinated around your equipment schedule.

Switchboard assembly with motor-control compartments in the Clive Wilson workshop
Mechanical plant, coordinated

One board.
A connected plantroom.

We work with mechanical contractors, electrical contractors, consultants and controls specialists to bring the power and control requirements together before manufacture.

01 / HVAC & ventilation

Air handling.
Heating. Cooling.

Supplies and motor control for air handling units, supply and extract fans, chillers and associated plant. Match the MSSB to each equipment supplier’s connection and control requirements.

02 / Pumps & water systems

Circulation.
Pressure. Duty control.

Control panels for single pumps and duty/standby arrangements, with starters or variable speed drives where specified. Coordinate run commands, operating feedback and changeover sequences.

03 / Refrigeration & plant

Packaged equipment.
Clear interfaces.

Power distribution and agreed control connections for refrigeration and other mechanical packages. Define what is supplied within the equipment and what belongs in the switchboard.

Built around your equipment schedule

The right power.
The right control.

Your MSSB can combine distribution, motor starting, protection and controls in a coordinated assembly. We establish the scope from the mechanical schedule, electrical drawings and equipment supplier data.

Power distribution and protection

Incoming supply, outgoing circuits, isolation and protection arranged for the nominated loads, fault conditions and installation requirements.

Motor starters and variable speed drives

Starters and VSDs can be included where required. Their location, heat load, access and cable routes are coordinated with the enclosure layout. Equipment with an integral starter or drive may only need a protected supply and control interface.

Local operation and identification

Local/off/automatic selection, indication and labelled terminals can be provided to suit the functional description. Circuit labels, drawings and BMS points use consistent equipment tags.

For wider process-motor applications, see our motor control centres. For ordinary lighting and power circuits, see our distribution boards.

Pump control switchboard showing circuit protection and control equipment
Coordinate power circuits, motor control and field connections before the assembly is built.
Working with your controls contractor

BMS connections.
Defined from the start.

A building management system (BMS) interface needs a clear point schedule and an agreed division of responsibility. CWS can manufacture the MSSB around your controls contractor’s requirements, including space and wiring for free-issued controllers where specified.

Interfaces to coordinate during design
InterfaceWhat we agree
Start and enableCommand source, connection type and the conditions that permit the equipment to run.
Running and healthyWhether feedback indicates a contactor, drive status or a proven physical condition such as airflow or pressure.
Speed and process referenceSignal type or network protocol, range, scaling and response to a missing reference.
Trips and alarmsIndividual or common alarms, fault indication and the required reset behaviour.
Local and automatic controlControl authority in each mode, mode indication and the interlocks that remain active.
External interlocksSignal source, required action and reset conditions, aligned with the approved sequence.

Controller supply, sensors, actuators, software, licences, field wiring and site commissioning are allocated in the project scope. Where additional controls work is required, discuss an automation and control package with us.

From a point list to an operating sequence

Built for the way
your plant operates.

Duty and standby pumps

Define duty selection, changeover, proof of operation and the response to a failed pump. Any automatic standby start follows the approved functional description.

Fans, dampers and proving signals

Coordinate damper position, fan commands, airflow or pressure proof, timers and alarm handling with the mechanical designer and controls contractor.

Packaged equipment

Coordinate enable signals, run permissions and faults with the manufacturer’s own controls and protection. Confirm which starters, drives and isolators are already included.

Power loss and restart

Agree the response to restored power or lost BMS communications, including any staged restart or operator acknowledgement required by the project.

Fire and smoke-control interfaces: any life-safety functions follow the project’s approved cause-and-effect, equipment requirements and testing responsibilities.

Manufacture, testing & handover

From approved drawings
to a tested assembly.

Factory testing covers the supplied wiring and agreed simulated control functions. Drawings, equipment tags and the BMS point schedule provide a common reference for the people installing and commissioning the plant.

Integrated site testing then proves the connected fans, pumps, dampers, sensors and packaged equipment. We agree the factory and site responsibilities with the project team.

Explore our switchboard design service

Before manufacture

Review the enclosure arrangement, cable entries, access, equipment schedule, control schematic and interface list against the agreed scope.

During factory testing

Check circuit identification, supplied wiring, commands, feedback and local/automatic operation against the approved test plan.

At handover

Provide the agreed drawings and test records, identify outstanding site interfaces and confirm who closes each item during commissioning.

Mechanical services questions

Plan your MSSB
with confidence.

A few decisions made early can simplify the interfaces between the mechanical package, switchboard and BMS.

What is a mechanical services switchboard?

A mechanical services switchboard, or MSSB, distributes power and provides the specified controls for building plant such as fans, pumps, air handling units and refrigeration equipment. It may combine circuit protection, motor starters, VSDs, local controls and BMS interfaces.

Can you build the board for our BMS contractor?

Yes. We can manufacture around the controls contractor’s controller, point schedule and wiring requirements. Confirm whether controllers are free-issued or included, and who provides software, field devices, wiring and commissioning.

Can VSDs and motor starters be included?

Yes, where required by the equipment schedule and approved design. Drives and starters may be fitted inside the board, mounted locally or included within the mechanical equipment. Their location is agreed before manufacture.

Does the factory test include the complete BMS?

The factory test covers the supplied assembly and the agreed simulated interfaces. Complete system testing takes place with the field equipment and BMS connected, under the project’s commissioning plan.

Do you supply mechanical switchboards across New Zealand?

Yes. CWS manufactures in Invercargill for mechanical services projects throughout New Zealand. Include the delivery location, site access requirements and required installation date with your enquiry.

Start with your plant schedule

Send us the brief.
We’ll work through
the details.

Send the information you have. We can identify the gaps with your project team and agree the switchboard scope before a detailed quotation.

Download the quote checklist (PDF)

For assembly requirements, use our switchboard specification guide and AS/NZS 61439 guide.

  1. Mechanical equipment scheduleEquipment tags, quantities, electrical loads, starting arrangements and supplier connection data.
  2. Electrical and enclosure requirementsSupply details, available fault level, required ratings, enclosure environment, plantroom layout and cable entry arrangements.
  3. Controls and BMS informationFunctional description, point list, controller requirements, interlocks, operating modes and approved sequences.
  4. Supply boundaries and programmeFree-issued equipment, drive locations, field wiring and commissioning responsibilities, delivery address and required site date.
Your next mechanical services project

Let’s build
your next MSSB.

Send your equipment schedule, drawings and controls requirements to our estimating team.

estimating@clivewilson.co.nzBased in Invercargill. Supplying projects throughout New Zealand.

Request an MSSB quoteOr call +64 3 214 4264