The Emerson/Artesyn/Astec LPS255-CEF is a 250 W AC-DC switch mode power supply designed as an off-board module for system integration applications. It delivers regulated 24 VDC output with wide-range adjustability and incorporates active power factor correction, remote sense and inhibit capabilities, and single-wire current sharing for parallel operation. The unit operates across universal input voltage ranges with built-in EMI filtering to Class B standards and includes comprehensive protection circuits, making it suitable for industrial control, telecommunications, and distributed power systems requiring efficient, reliable conversion.
## Technical Specifications
**Input Characteristics**
• Input voltage: 85–264 VAC or 120–300 VDC
• Input frequency: 47–440 Hz
• Active power factor correction reduces line harmonics and improves efficiency
• Inrush current: 20 A maximum at cold start, 25°C
• Safety ground leakage: <0.5 mA @ 50/60 Hz, 264 VAC
**Output Characteristics**
• Nominal output: 24 VDC with 2:1 wide-range adjustment capability (24–48 VDC)
• Load regulation: 2%
• Low output ripple and DC power good signal
• Supervisory outputs: 5 V @ 100 mA and 12 V @ 500 mA regulated
• Hold-up time: 20 ms at 250 W load, 115 VAC nominal
**Protection & Thermal Management**
• Short-circuit protection on all outputs
• Overload protection at 10–145% above rated capacity
• Overvoltage protection with selectable thresholds
• Thermal overload protection
• Fan-cooled operation; 30 CFM forced air cooling required if optional fans not installed
• Operating temperature: 0–50°C; derating 2.5% per °C from 50–70°C
**EMI & Regulatory**
• Built-in EMI filter: FCC Class B, CISPR 22 Class B, EN55022 Class B, VDE 0878 PT3 Class B
• Switching frequency: 120 kHz
## Key Features
• Remote sense compensates for voltage drop in load leads
• Remote inhibit enables software-controlled shutdown
• Single-wire current sharing simplifies parallel configuration for increased power delivery
• Power fail signal alerts host systems to input loss conditions
• Compact form factor: 261 × 127 × 50.8 mm
## Typical Applications
Distributed power architectures, industrial process control, telecommunications infrastructure, backup power systems, and multi-supply configurations requiring coordinated current sharing.
