Reliable power is essential on any worksite. When working off-grid, in a new development without mains connection or on remote properties, a dependable generator becomes a critical tool.

Choosing the right generator makes the difference between a productive workday & constant frustration. Selecting a unit that is too small results in overload trips while an oversized unit wastes fuel & adds unnecessary cost.

This generator buying guide explains how to choose the right unit based on your trade, worksite requirements & equipment load.

At Industrial Shed we stock a range of generators suited to Australian worksites & our team can help match the right model to your needs.

Inverter vs Conventional Generators

Understanding the difference between these two generator types is the first step in choosing the right equipment.

Inverter Generators

An inverter generator produces stable electricity with low Total Harmonic Distortion (THD), typically under 3%.

This clean power output makes inverter generators safe for sensitive electronics including:

• Laptops
  

• Battery chargers
  

• Laser levels
  

• Devices containing microchips or control boards
  

Inverter generators are also quieter than conventional models.

Most operate between 55 to 65 dBA at 7 metres, roughly similar to normal conversation.

They achieve this by automatically adjusting engine speed to match electrical load. Lower loads result in reduced engine speed which improves fuel efficiency.

Advantages of inverter generators include:

• Quiet operation
  

• Excellent fuel efficiency
  

• Clean stable power output
  

• Lightweight portable designs
  

The trade-off is higher upfront cost & slightly lower peak power output compared to conventional models.

These generators suit electricians, data technicians, painters & trades working with sensitive equipment.

Conventional Generators

A conventional generator uses a petrol or diesel engine driving an alternator to produce AC power.

These machines are built for high power output & durability.

Conventional generators typically operate at a constant 3000 RPM, meaning the engine runs at the same speed regardless of load.

Advantages include:

• High wattage output
  

• Lower purchase price
  

• Excellent performance for heavy tools
  

They are ideal for powering equipment such as:

• Angle grinders
  

• Circular saws

• Concrete mixers
  

• Welders without electronic controls
  

However they tend to be louder, heavier & less fuel efficient than inverter generators.

Comparison Overview

How Much Power Do You Need

Generator size is measured in watts.

Choosing the correct power output is essential to avoid overload shutdowns.

Generators usually list two ratings:

Starting Watts – peak surge power during tool startup
Running Watts – continuous operating power

Many electric motors require 2 to 3 times their running power during startup.

Your generator must support this surge requirement.

How to Calculate Power Requirements

1. List tools you will run simultaneously
   
   

2. Identify running wattage for each tool
   
   

3. Add all running watt values together
   
   

4. Identify the highest starting watt requirement
   
   

5. Add that surge value to the running total
   
   

The result is the minimum generator starting capacity required.

Common Tool Power Draw

Example calculation:

• LED lights: 300W
  

• Battery charger: 150W
  

• Circular saw: 1200W
  
  

Running load = 1650W

Add saw starting surge:

1650 + 2400 = 4050W

A generator rated around 3500 to 4500 watts would be suitable.

Key Generator Features to Consider

Beyond power output, several design features influence generator performance.

Power Outlets & Safety

Ensure the generator includes the correct outlet configuration.

Common options include:

• 240V 15A outlets for standard tools
  

• 240V 32A outlets for higher draw equipment
  

Generators should also include RCD safety switches which protect users from electric shock.

Weather protected outlet covers are useful for outdoor job sites.

Portability & Weight

Portability matters when transporting generators between worksites.

Look for:

• Solid wheels
  

• Fold down handles
  

• Balanced lifting points
  

Always check the dry weight before purchase.

Small inverter units may weigh 25 kg while large conventional units may exceed 90 kg.

Noise Levels

Generator noise is measured in decibels (dBA) at 7 metres.

Approximate comparisons:

• 55 dBA – quiet conversation
  

• 65 dBA – office environment
  

• 75 dBA – loud appliance
  

If working in residential areas, quieter inverter models may be preferred.

Fuel Type & Tank Size

Most portable generators operate on unleaded petrol.

Larger commercial units may run on diesel which offers improved fuel efficiency during long runtime applications.

A larger fuel tank reduces refuelling interruptions.

Fuel gauges are also useful during extended operation.

Electric Start vs Recoil Start

Many generators offer electric start push button ignition.

Electric start is convenient particularly for larger engines.

Most units also include recoil start as a backup option.

Generator Maintenance Tips

Regular maintenance keeps generators operating reliably.

Regular Oil Checks

Check oil levels before every use.

Oil changes are typically required every 50 to 100 hours of operation.

Running an engine with low oil can cause serious damage.

Maintain the Air Filter

Dusty worksites quickly clog air filters.

Clean or replace filters regularly to maintain engine performance.

Use Fresh Fuel

Petrol older than 30 days can cause starting problems.

For long storage periods drain the fuel or use stabiliser.

Run the Generator Regularly

Generators should be run under load for 15 to 20 minutes monthly to maintain internal components.

Store Generators Correctly

Store generators in dry well ventilated areas.

Protect units from dust, moisture & extreme weather conditions.

Our Recommended Generator Options

Industrial Shed stocks proven generator models suited to trade environments.

Westinghouse iGen4500s Inverter Generator

The Westinghouse iGen4500s is a quiet inverter generator delivering 3700 running watts & 4500 starting watts.

Advantages include:

• Quiet operation
  

• Clean stable power
  

• Excellent fuel efficiency
  

• Electric start
  

Ideal for residential worksites or sensitive electronics.

Westinghouse WHXC8500E Conventional Generator

The Westinghouse WHXC8500E delivers high output with 7000 running watts & 8500 starting watts.

Key advantages:

• High power output
  

• Durable construction
  

• Large fuel capacity
  
  

Best suited to remote worksites requiring heavy equipment power.

SP Power Equip SPGD6800E Diesel Generator

The SP Power Equip SPGD6800E provides 5000 running watts using diesel power.

Advantages include:

• Excellent fuel economy
  

• Long engine life
  

• Reliable continuous operation
  

Suitable for farms, remote worksites & backup power applications.

Need Help Choosing the Right Generator

Selecting the right generator depends on your tools, jobsite conditions & power requirements.

Visit our Somerville store on the Mornington Peninsula or contact our team for advice.

We can help calculate the correct generator size & recommend the best model for your work environment.

Browse our full generator range online or visit in store to see available models in person.

Industrial Shed is open:

Monday–Friday: 7:30 a.m. – 4:00 p.m.

Saturday & Sunday: Closed