Dedicated Circuits for Heavy Tools in Workshops

If you own a shed on a rural property and are contemplating transforming this space into a fully operational workshop, focusing on the electrical setup is essential.
Utilising equipment such as a MIG welder, air compressor, and table saw on a shared circuit with your home can result in serious complications, including frequent tripped breakers, flickering lights, and potentially dangerous overload scenarios.

This detailed guide delves into the critical aspects of creating a well-wired workshop in the rural areas of the Mid North Coast. We will cover crucial topics including dedicated circuits, sub-boards, and the benefits of employing three-phase power for larger machinery. If your requirements are limited to basic electrical needs for your shed—such as lighting and a few outlets—please consult our guide on Shed Wiring on Acreage for a more appropriate starting point. This article is specifically designed for workshops that require significant power.

Recognise the Critical Role of Dedicated Circuits in Your Workshop

Most residential properties use multiple power points on shared circuits, which works well for low-power devices like kettles and televisions. issues arise when trying to operate a 32-amp MIG welder alongside an air compressor at the same time. This situation can lead to significant electrical issues.

Here’s a breakdown of what could happen when you connect heavy machinery to household circuits:

• Frequent tripped breakers — A welder drawing more than 30 amps on a 20-amp circuit will trip the breaker immediately or, worse, could cause the wiring to overheat before the breaker can react.
• Voltage drops — Extended cable runs from the main board to the shed can cause voltage sag. This may result in your tools operating at higher temperatures, slower speeds, and leading to faster wear over time.
• Power interruptions in the home — Your partner might face a power outage in the kitchen due to your compressor being activated, leading to unnecessary arguments.
• Increased fire hazards — Overloaded wiring within walls and cable runs is a leading cause of electrical fires in rural environments.

Implementing dedicated circuits effectively addresses these problems. Each heavy tool is assigned its own circuit, correctly sized for its power needs, alongside individual breaker protection. This ensures that nothing is shared, and no circuit is overloaded.

Evaluate the Power Demands of Common Workshop Equipment

Before your electrician can create an efficient circuit layout, it is crucial to comprehend the power requirements of your equipment. Here’s a comprehensive overview of the typical power consumption for common workshop tools:

• MIG welder — Requires between 15A and 32A depending on the model. Larger 240V welders typically fall at the higher end, while three-phase units have different specifications (more on that later).
• Air compressor — Consumes about 10A to 15A. The startup surge can be significant, with compressor motors often drawing 3 to 4 times their running current for a few seconds upon initiation.
• Table saw — Typically uses 10A to 15A for a quality cabinet saw. More economical contractor models might draw less power, but opting for a budget option is not advisable.
• Lathe (wood or metal) — Like table saws, these generally require between 10A and 15A, with metal lathes usually at the higher end.
• Dust extractor — Around 10A for a single-phase unit, which needs to operate continuously while using other tools, thus necessitating its own circuit.
• Plasma cutter — Requires between 20A and 30A, similar to a welder, and also necessitates a dedicated circuit.

When you sum the power consumption, it becomes clear that a single 20-amp circuit from the house will fall short. A fully equipped workshop can easily demand 80 to 100+ amps across all circuits when operating at full capacity, emphasising the importance of strategic planning.

Select the Appropriate Circuit Breaker Size and RCD Protection for Safety

Every circuit in your workshop must be equipped with a breaker that matches the cable size and anticipated load. Your electrician will calculate this based on your equipment, but as a general guideline:

• 15A or 20A circuits — Suitable for general power points, dust extractors, lighting circuits, and lighter tools.
• 32A circuits — Necessary for welders, plasma cutters, and other heavy single-phase machinery.
• Three-phase breakers — Sized according to specific equipment requirements (details to follow).

RCD protection is indispensable. As per AS/NZS 3000 (the Australian Wiring Rules), all power and lighting circuits must have RCD (safety switch) protection. This is a legal obligation designed to safeguard against the high-risk nature of workshop environments.
Concrete floors, metal tools, dust, and moisture heighten the likelihood of earth faults. RCDs instantly cut power if a current leak to earth is detected, which can mean the difference between a minor shock and a serious injury.

Typically, your electrician will install a combination of RCDs and MCBs (miniature circuit breakers), or RCBO units that incorporate both functionalities. RCBOs are especially advantageous in workshops as a fault on one circuit does not disrupt power to others, enhancing safety and reliability.

Establish a Dedicated Sub-Board for Your Workshop's Electrical Needs

Instead of running multiple individual cables back to the main switchboard, installing a dedicated sub-board in your workshop is a more efficient solution. Here are the benefits:

• Shorter cable runs — A single heavy feed cable connects from the house (or a separate meter) to the workshop board, followed by shorter runs from the sub-board to each outlet. This setup reduces voltage drop and lowers cable expenses.
• Simplified fault diagnosis — Each circuit is clearly labelled and easily accessible in the workshop. If a breaker trips, you won’t need to return to the house to reset it, saving time and effort.
• Future expansion — A properly sized sub-board allows for additional circuits in the future, making it straightforward to integrate new tools as your workshop evolves.
• Isolation capability — You can turn off all workshop power from a single main switch without affecting the house's electricity, enhancing safety during maintenance.

If your house switchboard is outdated or operating at full capacity, an upgrade may be necessary before effectively powering the workshop sub-board. Older ceramic fuse boards may not safely accommodate the increased load.

A typical workshop sub-board configuration includes a main switch, individual RCBOs for each circuit, a dedicated lighting circuit, and a surge protection device. We will size the incoming feed cable based on the total expected load plus a buffer for future enhancements, ensuring optimal performance and safety.

Ensure Your Workshop Has Sufficient Lighting for Safety and Efficiency

Adequate lighting is essential for safety within your workshop. You must have clear visibility of your work, especially when handling sharp blades and hot materials. Here are some key lighting considerations:

• High-lumen LED battens — LED panels or battens provide bright, consistent illumination throughout the space. Aim for a minimum of 500 lux at bench height to guarantee visibility.
• Dust-proof fittings — Standard lights can become obstructed by sawdust and metal shavings. Opt for IP-rated fittings that resist dust and moisture for durability and safety.
• Task lighting at workstations — While overhead lighting illuminates the general area, focused lighting at the workbench, lathe, and drill press is crucial for precision work and safety.
• Separate lighting circuit — Lighting should operate on its own circuit, ensuring that you still have illumination if a power circuit trips. Being left in darkness next to a running table saw poses a substantial safety risk.

We have extensive experience with lighting layouts in commercial spaces. Our team can assist you in designing a workshop lighting plan that significantly enhances your working environment and safety.

Prepare for Effective Ventilation and Dust Extraction Circuits

When engaged in tasks such as woodworking or welding, ensuring adequate ventilation is as vital as having sufficient power. Dust extraction systems and exhaust fans necessitate their own dedicated circuits because:

• Continuous operation — Your dust extractor must run whenever you’re cutting. It cannot share a circuit with the tool it serves, as this compromises efficiency and safety.
• Motor startup loads — Dust extraction fans and collectors experience significant startup surges, akin to compressors, which require dedicated circuits.
• Interlocked switching — In an optimally designed workshop, the dust extractor can be wired to activate automatically when specific tools are powered on. This requires careful circuit design to ensure functionality.

Plan for at least one dedicated 15A circuit for dust extraction and another for general ventilation. If you’re implementing a cyclone-style dust collection system, it may need a 20A circuit based on motor specifications, ensuring efficiency and effectiveness in maintaining air quality.

Utilise Three-Phase Power for Enhanced Efficiency with Heavy Equipment

When involved in intensive metalwork or operating large compressors (5HP+) or commercial-grade woodworking machinery, single-phase power may reach its limits. Three-phase power offers numerous advantages:

• Increased power capacity — Three-phase motors are more efficient and provide greater power without the excessive startup surges associated with single-phase motors.
• Support for larger welders and plasma cutters — Industrial MIG/TIG welders and CNC plasma tables typically require three-phase power for optimal performance.
• Smoother operation — Three-phase motors function more smoothly and run cooler, extending the lifespan of your tools and machinery.

Access to three-phase power in rural areas on the Mid North Coast depends on availability at the street level. Some properties may already have a three-phase supply, while others might need a phase converter or a new connection from Essential Energy.
For further information, please refer to our guide on Do I Need Three-Phase Power on My Property?

If three-phase power is available, your workshop will require the installation of a three-phase switchboard with appropriately rated breakers and an effective earthing system to ensure safety and reliability.

Incorporate Surge Protection to Safeguard Your Equipment

Tools equipped with electronic controls, variable frequency drives (VFDs), digital displays, and inverter welders are susceptible to voltage spikes. Notably, your workshop generates surges each time a large motor starts or stops. Coupled with the voltage instabilities often found in rural power lines, your valuable equipment is at risk.

Installing a surge protection device (SPD) at the sub-board can intercept voltage spikes before they impact your tools. This is a cost-effective measure compared to replacing the electronic components of a $3,000 welder or a CNC controller, thus preserving your investment.

If your property is prone to storms (a common occurrence on the Mid North Coast), we recommend adding surge protection at the main switchboard to defend against lightning-induced surges that could damage your equipment.

For properties that depend on a generator for backup power, incorporating a generator changeover switch ensures seamless transitions between mains power and generator supply without risking back-feeding or harming connected equipment, providing peace of mind during power outages.

Consider Additional Features for Your Workshop Wiring

Here are several more features to incorporate into your workshop wiring from the outset:

• Ample power points — Install more power points and switches than you anticipate needing. Use weatherproof GPOs if the workshop is open-sided to ensure longevity. Consider double power points at every bench and outlets at key machinery locations to enhance accessibility.
• Data and communications — If you require internet access for streaming music, operating a CNC machine, or monitoring security cameras, plan for data and TV wiring concurrently with the electrical setup. Running cables during the initial fit-out is significantly easier than retrofitting after the walls are finished, preventing future complications.
• External lighting — Incorporate floodlights outside the workshop to facilitate access during early mornings and late evenings, especially in rural areas lacking street lighting, thus enhancing safety.
• EV or equipment charging — For those using electric equipment (battery-powered tools, an electric vehicle, or an electric quad bike), implement a dedicated charging circuit to prevent overloads on general outlets, ensuring efficient operation of all devices.

Accurately Assess the Cost of Your Workshop Electrical Setup

Cost estimates will vary based on the size of the workshop, the number of circuits required, and whether three-phase power is necessary. As a rough guideline for the Mid North Coast:

• Basic single-phase setup (sub-board, 4–6 circuits, lighting) — Starting from $5,000, providing foundational electrical support.
• Complete dedicated sub-board (8–12 circuits, multiple heavy tool circuits, dust extraction, comprehensive lighting design) — Starting from $10,000, ensuring sufficient capacity for serious workshop needs.
• Three-phase workshop build (three-phase supply, dedicated board, heavy equipment circuits, complete fit-out) — Starting from $15,000+, accommodating extensive power requirements.

These figures represent starting points. Complex layouts, lengthy cable runs from the mains, or the necessity for upgrades from Essential Energy will increase costs. We provide transparent quotes based on your specific workshop and equipment needs—no hidden fees, ensuring you know precisely what to expect.

Important Reminder: All Electrical Work Must Be Conducted by Licensed Professionals

This is a critical point. In New South Wales, all electrical wiring work must be carried out by a licensed electrician. This includes installing new circuits, sub-boards, power points, and connecting equipment. There is no DIY exemption for electrical work, even on your own property, to ensure safety and compliance.

Hack-It Electrical Solutions holds NSW Electrical Contractor Licence #230609C. We operate throughout Bellingen, Coffs Harbour, Sawtell, Nambucca Heads, Woolgoolga, Urunga, Dorrigo, Valla Beach, and Toormina, ensuring quality service.

Engaging in unlicensed electrical work can void your insurance, create significant safety hazards, and lead to fines. If someone offers to do the work cheaply without a licence, it’s not a saving—it’s a risk that can have serious repercussions.

Find Answers to Common Questions Regarding Workshop Electrical Requirements

Can I Use My Welder with a Standard Power Point?

Small stick welders (up to around 140A output) can be used with a standard 10A or 15A power point. Any larger units require a dedicated circuit. A MIG welder with a capacity of 200A or more connected to a 10-amp GPO will trip the breaker immediately—or potentially cause the wiring to overheat if the breaker is faulty. If you weld regularly, it’s essential to have a dedicated 32A circuit installed to ensure safe operation.

How Many Circuits Are Typically Needed in a Workshop?

The number of circuits required depends on your tools, but a well-equipped workshop typically needs a minimum of 8 to 12 circuits. This includes dedicated circuits for each heavy tool (welder, compressor, plasma cutter), general power point circuits, dust extraction, lighting, as well as a couple of spares for future additions. We customise the design based on your specific equipment list, ensuring you have everything you need.

Is Three-Phase Power Necessary for a Home Workshop?

Not necessarily. Most home workshops function effectively on single-phase power with dedicated circuits. Three-phase power is only required if you are using commercial-grade equipment, such as large compressors (5HP+), three-phase welders, or CNC machines. Refer to our comprehensive guide on Do I Need Three-Phase Power on My Property? to ascertain if it meets your requirements, ensuring you make an informed decision.

Can My Existing Switchboard Support a Workshop?

It’s possible. If your house switchboard is modern and has spare capacity, we can often connect a workshop sub-board to it. If it is an outdated ceramic fuse board or is fully loaded, an upgrade will be required before proceeding. We will assess this during the quoting process to ensure everything aligns with current standards.

What Is the Typical Duration for a Workshop Electrical Fit-Out?

A basic single-phase setup can typically be completed within 1 to 2 days. A full fit-out encompassing multiple heavy circuits, three-phase power, and comprehensive lighting generally takes 3 to 5 days, depending on complexity and cable run distances. We will provide a timeline along with your quote, ensuring you know what to expect.

Ensure Your Workshop Is Properly Wired for Safety and Efficiency

If you are setting up a workshop on your property and wish to ensure it is done correctly from the outset, reach out to us. We will visit your site, evaluate your space and equipment list, and develop a plan that meets your power requirements without compromising safety or quality, ensuring a successful workshop setup.

Contact Hack-It Electrical Solutions at 0402 079 803 or get in touch with us online to arrange a detailed quote and consultation.

We are your local electricians in Bellingen, proudly serving the entire Mid North Coast from Nambucca Heads to Woolgoolga and up to Dorrigo.