1200W AC/DC power supply

Power Box (PRBX) announced the release of the OFI1200A 1200W AC/DC power supply for industrial applications. Optimized for conduction cooling, the OFI1200A offers high levels of performance over a base plate temperature range of -40 to +95°C without the use of a fan. The power supply operates with a wide universal input range of 85 to 305 VAC with power factor correction (PFC). Covering a wide range of applications, its output voltage and current can be adjusted from near zero to the maximum allowed for each model.

A number of industrial applications require power supplies to operate with limited or no fan cooling. As such, those operating in harsh environments where electronic equipment is installed in a weatherproof enclosure, radio communication systems subject to adverse weather conditions, outdoor displays and road signs, and indoor equipment with noise restrictions audibly very strict. In addition to environmental requirements, reliability and cost of maintenance drive system designers away from using fans and blowers.

Optimal heat transfer

The PRBX OFI1200A has been designed to guarantee optimal heat transfer from the heatsink components to the base, providing a high level of performance at an operating temperature of -40 to +95 degrees centigrade at the base plate. Depending on the mounting method and the general cooling conditions, a derating may apply as specified in the technical documentation.

To cover a wide range of applications, the OFI1200A operates with a wide universal input range of 85 to 305VAC (Nominal 100 to 277VAC). The unit includes a PFC with a coefficient of 0.98/0.95 (110VAC/230VAC).

The OFI1200A is available in three single voltage DC output versions, 12V/84A; 28V/43A and 48V/25A. Using a high efficiency topology, typical efficiency from the 48V output unit to the 230VAC input is an excellent 92%.

Adjustment of output voltage and/or current from maximum allowed to near zero

Industrial applications such as professional lighting or even low-power electrolyzers require the power supply to deliver a constant current, and this must be easily adjustable. Often, this equipment is used in environments that require the electronics to be enclosed and protected from hazards. This requires the power supply to offer an external command to adjust the output voltage and/or current from the maximum allowed to near zero.

To allow customers to precisely match voltage and current to their application, the OFI1200A offers two analog inputs, VTRM and ITRM. Using these functions, the output voltage and current can be adjusted from near zero to the maximum specified per model. For example, the 28V output can be adjusted from near zero volts up to 33.6V, and the output current from near zero amps up to 43A. The output voltage can also be adjusted using the integrated potentiometer provided.

Extensive tuning and control functionality simplifies the use of the power supply in constant voltage (CV) or constant current (CC) mode, without adding external circuitry.

For applications requiring redundancy or higher power, up to nine units can be connected in parallel, delivering an impressive total power level of up to 9720 W in conduction cooling mode. To maintain the highest level of efficiency when used in parallel or redundant mode, an optional active ORing circuit deploying high performance FET technology (Option-O) is available on the OFI1200A28 and OFI1200A48.

For safety reasons, the OFI1200A has IN/OUT isolation of 3000VAC and IN/FG of 2000VAC. Output isolation to FG is 500 VAC. The power supply includes overcurrent protection with automatic recovery, as well as overvoltage and overtemperature protection.

Easy access to auxiliary functions via on-board connectors, namely: remote control, output voltage detection, Power Good, VTRM, ITRM

The OFI1200A has passed the shock and vibration tests specified in MIL-STD-810H. In this regard, the products have been tested at levels well above normal operating conditions and are designed to withstand high level 20G shock.

In its open-frame form factor, the OFI1200A measures 142 x 39 x 260 mm (5.59 x 1.54 x 10.36 inches) and weighs 1.2 kg max. An optional metal cover is available, adding only 1 mm to the height and 200 grams to the weight (Option-N).

Benefiting from a design optimized for conduction cooling, the OFI1200A is suitable for applications requiring a quiet power solution like in a control room. It is also suitable for industrial applications where forced ventilation is not possible due to environmental constraints. Attached to a chassis or cold plate, the OFI1200A can deliver impressive power levels with a high level of reliability. The OFI1200A is certified in accordance with UL62368-1 3rd Edition, cUL (equivalent to CAN/CSA-C22.2 No.62368-1).

The OFI1200A series is backed by a full three-year warranty and complies with EU RoHS, REACH and low voltage directives. The product bears the CE, UKCA and cURus marks.

Alan A. Seibert