Powering the Tight Squeeze in Industrial Control Systems

Open up an industrial control cabinet, and the first thing you’ll notice is how much is being asked of a very small space. Controllers, communication modules, and I/O systems are being packed more tightly, even as power levels continue to climb. It creates an almost pressure-cooker effect if you consider the issue of keeping heat under control within such a limited footprint.

This leaves design engineers in a position where they have to weigh some trade-offs. Higher-end power supplies can address thermal and safety requirements but may exceed the budget of the application. Lower-cost options may reduce upfront cost, but can bring about concerns related to efficiency, cooling, and compliance.

TRACO Power addresses these challenges with its TXO series (Figure 1). Spanning 45 W to 500 W, the open-frame AC/DC lineup is designed for cost-sensitive industrial applications that need to make careful use of space while supporting safe, predictable operation.

Figure 1: A representative example of the TXO series. (Image source: TRACO Power)

TXO 45

The TXO 45 is the entry point to the series, serving lower-power industrial applications. It provides 45 W in a compact 2” x 3” open-frame format, which fits easily into control boards, embedded systems, and sensor-based equipment. The unit uses a flyback converter topology, placing it at the simpler end of the TXO lineup.

The TXO 45’s fanless, convection-cooled design is well suited to systems that do not require forced-air cooling—keeping thermal management straightforward. Typical efficiency is around 85%, and it is available in 12, 15, 24, and 48 V versions for a range of smaller automation and control tasks.

TXO 60

The TXO 60 is the next step up from the TXO 45, delivering 60 W in the same 2” x 3” form factor. It is a good fit for expanded control systems, retrofit designs, and applications that need a modest power increase without moving to a larger footprint.

The TXO 60 also uses natural convection cooling and delivers efficiency around 85%. No-load power consumption stays below 100 mW, keeping power draw low while the supply is idle. The TXO 60 also offers a hold-up time of 60 ms at 230 VAC, allowing the output to remain stable through brief dips in the incoming AC supply.

TXO 120

The TXO 120 has the same 2” x 3” footprint, pushing it to its highest output level at 120 W. It is intended for dense control panels, IoT gateways, communication hubs, and other systems where room is limited but power needs are growing.

The TXO 120 uses LLC converter topology, which helps raise efficiency to as high as 92% and reduces wasted heat at higher output levels. It also adds active power factor correction, drawing power from the AC line in a cleaner, more controlled way. Under natural convection, the unit is rated for 100 W up to +50°C. With forced-air cooling, it can deliver the full 120 W up to +50°C.

TXO 150

The TXO 150 is where the series moves beyond the compact 2” x 3” format and into a larger 2” x 4” footprint to accommodate a 150 W output. The added board area eases thermal demands at this power level and makes the unit a better match for industrial controllers, HMI systems, and mid-power automation equipment.

Like the TXO 120, it uses LLC converter topology and active power factor correction. With typical efficiency of 90%, the TXO 150 is built for higher sustained loads. It is rated for 120 W under natural convection up to +50°C, or the full 150 W with forced-air cooling.

TXO 300

The TXO 300 moves into a larger open-frame chassis of roughly 3” x 5”, reflecting the increase to a 300 W output. It is aimed at complex automation platforms, industrial controllers, and test and measurement equipment, where the controller needs more visibility into power conditions.

The TXO 300 also uses LLC converter topology and active power factor correction. Efficiency reaches up to 88%. The larger shift is that the TXO 300 brings the power supply into closer coordination with the rest of the system. Remote on/off allows the system controller to place the power supply in standby without removing AC input power. A Power Good signal tells the controller when the DC output is stable and within tolerance, helping prevent startup during a brownout or fault. The 5 V standby output keeps low-power control logic running when the main output is off, while remote sense corrects for voltage drop across longer cable runs.

Full 300 W output requires forced-air cooling. Under natural convection, the output is 180 W for the 12 V and 15 V models, and 200 W for the 24, 36, 48, and 56 V versions.

TXO 500

The TXO 500 is the top end of the series, moving into a 4” x 6” package with an L-bracket for chassis mounting, delivering up to 500 W for larger machines, industrial automation lines, test and measurement platforms, and high-power control systems. Output current reaches as high as 37.5 A on the 12 V model, extending the series into applications such as motors, actuators, and high-end processing boards.

The TXO 500 carries the same smart integration features as the TXO 300 to coordinate power behavior at the system level. It includes remote on/off, a Power OK signal, a 5 V standby output, and remote sense. It also adds output voltage adjustment, allowing the nominal DC output to be trimmed within a limited range to better match system requirements. The TXO 500 uses LCC converter topology, helping it reach efficiency as high as 92%. It also retains active power factor correction.

Under natural convection, the output is rated at 240 W for the 12 V and 15 V models, and 290 W for the higher-voltage versions. With forced-air cooling, the output rises to 450 W for the 12 V and 15 V models, and the full 500 W for the other versions.

Shared Characteristics Across the TXO Series

The TXO series features several core characteristics. Reinforced 3000 VAC input-to-output isolation appears throughout the lineup—rarely found outside of medically approved products—providing separation between AC input and low-voltage output to protect workers and sensitive electronics.

All TXO models are certified to IEC/EN/UL 62368-1 safety standards, enabling reliable integration into globally compliant industrial equipment without additional safety redesign. Built-in EN 55032 Class B EMC filtering limits electrical noise and interference while reducing the amount of external filtering required.

The TXO family incorporates short-circuit, overvoltage, and overcurrent protection, helping prevent damage to both the power supply and downstream components during fault conditions. The series operates from -20°C to +70°C, with full-load operation to +50°C and continued operation to +70°C with derating.

To learn more, visit Traco Power TXO Series AC/DC Power Supplies.