High power density built-in power supply

RECOM, a leading global manufacturer of AC/DC and DC/DC converters, launches the 1.2kW AC/DC power supply RACM1200-V. Developed in Austria and manufactured in Europe, the converter has all the relevant certifications for medical applications. With transport routes and supply chains becoming increasingly shorter, RECOM is committed to sustainability.

Robots are an example of a power supply that requires more than 1kW. Robots are used in industry, but are increasingly also used in the medical field. When the robot assists the surgeon, it must move to the desired position accurately and smoothly without vibration, so a rigid robot arm driven by a high-torque stepper motor is required. The power consumption of the motor is relatively high. Fans are prohibited in operating rooms for hygienic reasons, so the power supplies must be base-cooled. At the same time, they must meet higher insulation requirements, such as IEC/EN or ANSI/AAMI 60601-1 (3rd edition), which are more stringent than those for industrial use. Power supplies that are certified for medical use can also be used in industrial applications, but not vice versa.

Figure 1: Medical collaborative robot

If the power supply is to supply equipment that is in direct contact with the patient, they must have double insulation and twice the creepage distance, and must comply with the so-called 2xMOPP insulation protection measures. "The safe choice is the only choice" is RECOM's unchanging principle for the RACM1200-V. The RACM1200-V has passed all the certification tests required for medical use.

The RACM1200-V sets a new benchmark in ultra-compact design by operating over a wide power range without a fan. Special baseplate cooling supports up to 1000W of continuous output. Two additional outputs replace the auxiliary power supply required in many applications. For example, one of the outputs can be regulated in the range of 5V to 12V and power a fan. The second output provides 5V/1A and can also operate continuously when the power supply is in standby.

With a high isolation strength of 4kV (AC) between the supply voltage and the output voltage, the RACM1200-V can be used almost everywhere where a power supply is needed. These can be chargers or LED lighting, but also laser equipment, analytical equipment, high-frequency equipment, robots or medical beds and chairs, as well as medical equipment that comes into direct contact with patients. Developers of the above equipment can therefore choose to use a power module that already meets the required specifications.

Although a fully IEC 60601-1 certified power supply does not guarantee that the entire device complies with IEC 60601-1, it is a necessary prerequisite. This not only greatly helps in the certification process of the final product, but also saves development costs.

These modules are designed to ensure 2xMOPP (Measures of Patient Protection). The patient protection measures coupled with low leakage current ensure compliance with medical safety standards.

The signal outputs and 5V outputs are isolated from the supply voltage by 1.5kVAC.

The series is equipped with built-in EMC filters, has sufficient Class B electrical clearance to avoid radiated and conducted interference, and complies with international safety standards related to industrial applications, information technology products and medical equipment.

A single 1200W AC/DC converter is sufficient for many applications and can replace multiple smaller converters. A single high-power AC/DC converter can run at higher power than multiple smaller converters. Although individual power supplies keep internal power dissipation as low as possible, the internal power dissipation of multiple power supplies still adds up. For example, if an equipment rack is equipped with twelve independent 100W power supplies, each with an internal power dissipation of 2W, the total losses add up to 24W. In contrast, a single large converter would only lose 2W. If the gear tray is running continuously, the savings can be approximately 200 kWh per year. The RACM1200 has a no-load power consumption of 0.75W (primary output off, auxiliary outputs remain operational), meeting the efficiency requirements of "80 Plus Platinum" and "Ecodesign Lot 6".

The input voltage range is 85VAC to 264VAC. The RACM1200-V provides 1000W output power and is housed in a metal case with contact cooling and a volume of only 102mm x 229mm x 40mm. Output power can reach 1200W and can be maintained for more than 10 seconds. However, to achieve 1200W continuous output, a fan and 2.5m/s air flow are required. The fan can be controlled by the user, and a controllable auxiliary output is provided for temperature management.

Important data of RACM1200-V

Output power: 1000W at 40°C ambient temperature and 230V input voltage; up to 1200W with fan or short peak load.

Dimensions including connector (L x W x H): 228.0mm x 96.2mm x 40.0mm; Connectors from other suppliers are subject to mechanical shock.

Power density: 

Efficiency: 95%, see Figure 2.

Power factor: See Figure 3.

Figure 2: Efficiency curve

Figure 3: Power factor

• Weight: 1kg (standard)

• Input voltage: 85V to 264V

• The output voltage:

• The 24V type is adjustable from 100mV to 28V via a DIP switch.

• The 48V type is adjustable from 200mV to 56V via a DIP switch.

• Maximum output current: 50A @ 24V, 25A @ 48V.

• Protection functions for main output and auxiliary voltage:

• -Overload protection, automatic reset

• -Over current and short circuit protection, automatic reset

• - Overheat protection, automatic restart

• Temperature range: -40°C to 80°C, derating starts at 50°C; see data sheet for details

• Lifetime at 40°C ambient temperature: 88,000 hours

• Maximum output voltage ripple: 1% of output voltage

• Output voltage tolerance: 1% typical at 25°C, ±2% maximum at higher temperatures

• Standard certification: IEC/EN 62368, UL/IEC/EN 60601

• Complies with IEC/EN 61558-2-16, IEC61010-1 and IEC62477-1 OVC II up to 2000m

• Cooling is done via aluminum baseplate or forced air flow.

• Maximum operating altitude: 5000m (IEC/EN62368-1), 4000m (IEC/EN60601)

• Auxiliary output voltage: 5V/1A, insulation

• - Standby power consumption: <1W (EcoDesign)

• LED operating status indicator: easy to use and provides extra safety

• Remote on/off: TTL input

• AC OK: open collector output

• PSU Good: Open Collector Output

• PSU Good: Open collector pin, power supply is operating normally, output voltage is normal, temperature is within the allowable range, no internal faults. Provides additional safety, reliability and power quality.

• Maximum patient leakage current: 100μA NC (normal condition) and 500μA SFC (single fault condition)

• Medical safety classification: 2MOPP

Precisely controlled output voltage: The power supply is equipped with a remote sense function to eliminate the occurrence of line voltage drops and uses two additional sense lines to measure and control the output voltage at the relevant point. This solution eliminates voltage drops in high current (25A/50A) lines and is activated by 2 TTL inputs (5V).

Figure 4: Remote sensing of main output voltage

Other models in the RACM series:

Figure 5: The RACMxx series of power supplies for medical applications (from left): 230W, 550W, and 1200W.