Welcome to Controls Traders, located in Adelaide, South Australia. We are a supplier of quality building automation controls and peripheral products for the HVAC industry. We stock a full range of controllers, sensors, valves and actuators, damper actuators and accessories to suit any application. Our aim is to provide our customers with the highest level of service, from sales to delivery and after sales support. With our extensive in-house knowledge and expertise in the industry, we can advise you on selection and application of our wide range of controls products.
Backed by 40 years industry experience. When you just need to be sure.
No, we’re serious. Anywhere. Anytime.
We stock all major global brands. And if we don’t have it, we’ll find it.
We warehouse the stock so you don’t have to wait.
$150.00 ex GST
If you walk into the plant room of a hospital in Melbourne or an office block in Sydney built before 2000, there is a good chance you will hear the hiss of compressed air.
Pneumatic controls—relying on 3–15 psi signals to open valves and dampers—were the industry standard for decades. They are durable and safe, but they are also "dumb." They drift, they leak, and they offer zero data visibility.
For modern facility management, "blind" systems are no longer acceptable. The push for NABERS ratings and energy efficiency is driving a massive wave of retrofits across Australia and New Zealand.
At Controls Traders, we supply the hardware for these upgrades every day. Whether you are planning a full rip-and-replace or a hybrid integration, here is the technical workflow for retrofitting pneumatics to a digital Building Management System (BMS).
In a legacy pneumatic system, a compressor sends air to a Receiver-Controller (RC). Thermostats act as bleed valves; as the room warms up, the thermostat changes the air pressure in the line. This pressure change physically inflates a diaphragm on a valve or damper actuator to move it.
While mechanically ingenious, these systems have no memory and no feedback loop. If a damper is stuck, the compressor just keeps pushing air, and the facilities manager has no idea until a tenant complains.
The ROI on replacing pneumatics is usually driven by three factors:
To convert air to electrons, you generally need three categories of hardware:
Unlike pneumatics, digital actuators need to be "taught" their limits.
Once the hardware is installed, the BACnet Controllers come into play. Instead of a simple proportional band (like a pneumatic thermostat), you now configure PID loops in the software. This allows you to implement strategies that were impossible before, such as:
Retrofitting pneumatic controls extends the life of mechanical plant and drastically cuts energy bills. While the upfront labour is significant, the removal of compressor maintenance and the gain in control precision pays for itself.
At Controls Traders, we have 40 years of industry experience helping contractors navigate these upgrades. We stock the actuators, linkage kits, and controllers you need in Adelaide, ready for Australia-wide delivery.
Ready to start your retrofit? Read the full guide on our website for retrofit tool lists and product recommendations.
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If you are managing a commercial building in Australia, you know that HVAC consumption typically accounts for 40–50% of your total electricity bill. Within that plant room, supply and extract fans are often the biggest culprits of energy waste.
The solution isn't just buying newer fans; it is controlling the ones you have intelligently.
At Controls Traders, we have supplied building automation components for over 40 years. One of the most effective upgrades we see for immediate ROI is the installation of Variable Speed Drives (VSDs). This guide explains the physics behind the savings and how to apply them to your facility.
In short, Variable Speed Drives reduce HVAC fan energy use because they:
1. Match fan speed to real-time airflow demand instead of running at full speed.
2. Exploit the fan affinity laws, where small speed reductions deliver large energy savings.
3. Enable intelligent control via BMS signals, pressure sensors, and CO₂-based demand control.
A Variable Speed Drive (VSD)—also known as a Variable Frequency Drive (VFD)—is an electronic device that controls the speed of an AC induction motor by varying the frequency and voltage supplied to it.
Think of a VSD as a "dimmer switch" for your heavy industrial motors. Without a VSD, your AHU (Air Handling Unit) fan is either OFF or running at 100% full speed. With a VSD, that same fan can run at 40%, 60%, or 95%—matching the exact airflow required by the building at that moment.
Most HVAC systems in Australia are designed for "Design Day" conditions—the hottest days of the year (e.g., a 40°C day in Adelaide or Western Sydney).
However, these peak conditions occur for only a fraction of the year. For the remaining 95% of the time, the building operates at partial load. If your supply fans are running at full speed during mild weather, you are pushing more air than necessary.
In older systems without VSDs, this excess air is often choked back using mechanical dampers or inlet guide vanes. This is the energy equivalent of driving your car with your foot flat on the accelerator and controlling your speed by riding the brakes. It is inefficient and mechanically stressful.
A VSD replaces the need for mechanical throttling. By receiving a signal from your Building Management System (BMS) or a standalone controller, the VSD slows the motor itself down.
The financial magic of VSDs lies in the Fan Affinity Laws.
While flow is proportional to speed, power is proportional to the cube of the speed. This is known as the "Cube Law." $$Power \propto Speed^3$$
This means a small reduction in fan speed results in a massive reduction in energy consumption.
Let’s look at the math for a standard supply fan running at 80% speed (a 20% reduction):
The Result: By slowing your fan down by just 20%, you reduce its electricity consumption by roughly 50%. Even a modest reduction of 10% speed saves nearly 30% in energy. This is why VSDs offer such a rapid payback period.
VSDs are versatile and can be applied to almost any rotating equipment in the plant room:
While VSDs are powerful, they require correct installation:
Beyond the electricity bill, VSDs reduce mechanical wear. By "soft starting" the motor (ramping up slowly), you eliminate the high-torque shock of "Direct On Line" (DOL) starting, which extends the life of belts, bearings, and couplings.
For most commercial buildings, the ROI on a VSD retrofit is typically under 2 years, making it one of the most attractive CapEx projects for facility managers.
If your HVAC fans are running at constant speed while your building load varies, you are paying for energy you don't use. Implementing Variable Speed Drives allows you to harness the Cube Law, turning a 20% speed reduction into a 50% energy saving.
At Controls Traders, we warehouse a range of drives and controls suitable for the Australian market, ready for fast delivery.
Ready to upgrade your plant room? Read the full guide on our website for installation specs and recommended models. Browse our range of Variable Speed Drives and Test Instruments to get started.
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For HVAC installers and BMS technicians, the "set and forget" approach to sensor installation is a relic of the past. In modern Demand Control Ventilation (DCV) strategies, the CO₂ sensor is the heartbeat of the system.
If a temperature sensor is off by a degree, someone puts on a jumper. If a CO₂ sensor is poorly placed, the BMS either drastically under-ventilates (causing high PPM, drowsiness, and NCC compliance issues) or over-ventilates (pulling in unconditioned outside air and destroying energy efficiency).
At Controls Traders, backed by over 40 years of industry experience, we know that the sensor is only as good as its location. This guide covers the technical best practices for placing CO₂ sensors in open-plan offices to ensure accurate Indoor Air Quality (IAQ) monitoring.
In short, correct CO₂ sensor placement in an open-plan office is critical because it:
1. Ensures the BMS responds to actual occupant CO₂ levels, not diluted or stagnant air.
2. Prevents over- or under-ventilation that impacts indoor air quality and energy efficiency.
3. Enables effective demand-controlled ventilation in VAV and fan coil systems.
In a VAV (Variable Air Volume) or fan coil system, the CO₂ reading directly influences the damper position. The goal is typically to maintain indoor CO₂ levels below 800–1000 ppm (parts per million).
If a sensor is placed in a "dead zone" where air doesn't circulate, it may read 600 ppm while the occupied zone is hitting 1200 ppm. Conversely, placing a sensor directly in the path of supply air will result in artificially low readings, tricking the BMS into shutting down fresh air intake when it is needed most. Correct placement ensures the BMS reacts to the actual load generated by the occupants.
Unlike temperature, which equalizes relatively quickly, CO₂ is a heavy gas generated by point sources (people). In a calm open-plan office, CO₂ tends to pool around occupants before diffusing into the general return air path.
However, office air is rarely still. The HVAC system creates currents. Therefore, the sensor must be placed where it captures the mixed air representative of the breathing zone, not a stagnant pocket or a diluted airstream.
The "Golden Rule" of sensor placement is to measure the air that people are actually breathing.
For an open-plan office where occupants are mostly seated, the sensor should be mounted between 1.2m and 1.5m from the finished floor. This aligns with the seated breathing height and is generally consistent with light switch height for ease of cabling.
Avoid: Ceiling mounting for open-plan control sensors. While ceiling sensors are common, CO₂ concentration at the ceiling (near the return plenum) can differ significantly from the breathing zone, especially in high-ceiling spaces or systems with poor mixing.
Mount the sensor on an internal column or partition wall. Avoid: External walls. Although modern sensors often have temperature compensation, external walls act as thermal bridges. If you are using a combined Temp/CO₂ unit (like those from Sensors & Transducers ranges), the radiant cold or heat from an external wall will skew the temperature reading, even if the CO₂ reading is acceptable.
Installers often compromise on location to save cabling time. Avoid these three common "sensor killers":
A single sensor cannot effectively monitor a 500sqm floor plate.
Scenario: A 100m² open-plan zone with 10 desks and south-facing windows.
Correct CO₂ sensor placement is the difference between an efficient, compliant building and one that generates constant "it's stuffy in here" complaints.
Always aim for the breathing zone (1.2m–1.5m), use internal walls, and ensure one sensor per mechanical control zone.
At Controls Traders, we stock a wide range of reliable HVAC Room Sensors and combined units from trusted brands like Siemens, BAPI, and Automated Components Inc (ACI).
Unsure which sensor fits your BMS specification? Read the full guide on our website for placement diagrams and product suggestions.
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For HVAC installers and building automation technicians, selecting the right control valve is fundamental to system stability. While the industry has largely shifted toward variable flow systems, we still see plenty of 3-way valves in older Australian plant rooms.
Understanding the physics and hydraulic impact of 2-way vs. 3-way valves is critical—whether you are commissioning a modern VAV system or retrofitting a legacy constant-volume chiller.
At Controls Traders, we stock a wide range of Control Valves from brands like Belimo and Siemens. Here is a technical breakdown of the differences and when to use each.
A 2-way valve has two ports: an inlet (A) and an outlet (AB). Its primary function is to throttle the flow of water through a coil to control temperature.
A 3-way valve has three ports: an inlet (A), a bypass (B), and a common outlet (AB).
|
Feature |
2-Way Valve |
3-Way Valve |
|
Flow Characteristic |
Variable Flow (Varies with load) |
Constant Flow (Always 100%) |
|
Pump Energy |
High Efficiency: VSD pumps ramp down at part load. |
Low Efficiency: Pumps run at 100% speed continuously. |
|
Water Temperature |
Return water temp rises at part load (High ΔT). |
Return water temp drops at part load (Low ΔT). |
|
System Cost |
Lower piping cost (2 pipes), higher control complexity (requires VSDs). |
Higher piping cost (requires bypass piping), simpler pumping (no VSDs). |
Almost all modern Green Star or NABERS-rated buildings in Australia utilize 2-way valves. By using 2-way valves paired with Belimo Valves or Pressure Independent Control Valves (PICVs), you maximize the efficiency of variable speed pumps.
If you are replacing a valve in an old system (pre-2000s) that utilizes constant speed pumps without VSDs, you generally must replace like-for-like with a 3-way valve.
Even in modern variable flow systems, you will often see a single 3-way valve installed at the furthest FCU from the pump.
Choosing between 2-way and 3-way valves isn't just about plumbing; it's about the entire hydraulic strategy of the building.
At Controls Traders, we warehouse a massive stock of both valve types from trusted brands like Belimo, Siemens, and Honeywell. If you are retrofitting an old plant room and need to cross-reference a part number, our team has over 40 years of experience to help you get it right.
Read the full guide on our website for diagrams and selection tips.
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