The MEAN WELL SCP-50-12 is a 13.8 V single-output AC/DC power supply rated at 3.6 A and 49.7 W. It provides separate battery-backup connections, an L voltage-detection lead and optional temperature compensation in a convection-cooled metal enclosure.
Product Datasheet
Download MEAN WELL SCP-50 Datasheet (PDF)
The SCP-50 section is on PDF pages 4, 5, 6. Refer to the complete mechanical drawings and notes when planning installation.
Model and Output Ratings
| Full model |
SCP-50-12 |
| Series |
SCP-50 |
| DC output voltage |
13.8 V |
| Rated output current |
3.6 A |
| Rated output power |
49.7 W |
| Output current range |
0–3.6 A |
| Peak output current |
4.3 A |
| Output voltage adjustment |
+15% / −5% |
| Ripple and noise, maximum |
120 mVp-p |
| Voltage tolerance |
±2.0% |
| Line regulation |
±1.0% |
| Load regulation |
±2.0% |
This is a single-output switching power supply with dedicated battery connections for backup operation. The 12 model code identifies the nominal battery-voltage class; its rated supply output is 13.8 V. The B+ and B− terminals are for the external battery, while +V and −V supply the load.
Peak current is limited to 5 seconds, with a maximum 33% duty cycle in each 15-second period. Average output power must remain within the rated output power. Observe the input-voltage and ambient-temperature derating curves at the same time.
Input and Electrical Performance
| Input voltage range |
85–264 VAC; 120–370 VDC |
| Input frequency |
47–63 Hz |
| Typical efficiency |
81% |
| Typical AC input current |
1.1 A at 115 VAC; 0.65 A at 230 VAC |
| Typical cold-start inrush current |
45 A |
| Leakage current |
Less than 2 mA at 240 VAC |
| No-load power consumption |
Less than 0.75 W |
| Set-up / rise time at full load |
600 / 30 ms at 230 VAC; 1200 / 30 ms at 115 VAC |
| Typical hold-up time at full load |
50 ms at 230 VAC; 16 ms at 115 VAC |
| Switching frequency |
60 kHz |
Unless otherwise stated, electrical specifications are measured at 230 VAC input, rated load and 25°C ambient. Ripple and noise are measured with a 20 MHz bandwidth, a 12-inch twisted pair and parallel 0.1 µF / 47 µF capacitors. Voltage tolerance includes set-up tolerance, line regulation and load regulation.
Protection and Battery Connections
| Overload threshold |
4.3–5.8 A |
| Overvoltage threshold |
16.6–19.3 V |
| Short-circuit and overload response |
Hiccup mode; automatic recovery after the fault is removed |
| Overvoltage response |
Output shutdown; reapply input power to recover |
| Battery reverse-polarity protection |
Fuse protection |
| Input fuse FS1 |
F3.15A / 250 V |
| Battery fuse FS2 |
F6.3A / 250 V |
Connect B+ to battery positive and B− to battery negative. Do not connect a battery to the load-output +V / −V terminals. The battery is external; select its voltage and protection to suit the application.
The battery connection provides backup operation and optional temperature compensation of charging voltage. It is not a separately specified programmable multistage battery charger.
Voltage Detection and Temperature Compensation
| L detection lead, AC normal |
Output voltage + 0.2–0.7 V, depending on the diode forward drop |
| L detection lead, AC failure |
0 V |
| CN2 temperature-sensor reference |
100 kΩ THINKING thermistor |
| Compensated voltage at 0°C |
14.4 ± 0.2 V |
| Compensated voltage at 25°C |
13.8 ± 0.1 V |
| Compensated voltage at 50°C |
13.2 ± 0.2 V |
The L lead detects output or battery voltage; it is not a fixed-voltage logic supply. A temperature sensor can be connected at CN2 to compensate charging voltage. The sensor is not included, and normal operation is available without it.
The compensation values are the catalogue reference example at the rated DC output setting. If the internal voltage adjustment changes the rated setting, consult MEAN WELL for the appropriate thermistor selection.
Terminals and Mating Parts
| TB1 input pins |
1: AC/L; 2: AC/N; 3: FG |
| TB2 output pins |
1: DC +V; 2: DC −V |
| Battery and detection lead colours |
B+: red; B−: black; L: yellow |
| Load-output lead colours |
+V: orange; −V: black |
| Drawing lead-length reference |
400 mm |
| CN2 board connector |
JST B2B-XH or equivalent |
| CN2 mating housing |
JST XHP series or equivalent |
| CN2 mating contact |
JST SXH-001T-P0.6 or equivalent |
Use the terminal and lead markings in the mechanical drawing to distinguish the two black return leads. Select the complete XHP housing for the circuit count and wire assembly required by the drawing. Mating parts and the temperature sensor should be specified separately; their references do not describe an included cable kit.
Cooling and Operating Limits
| Cooling |
Free-air convection |
| Working temperature |
−20 to +60°C, subject to derating |
| Horizontal temperature curve |
100% load from −20 to 50°C; 60% load at 60°C |
| Input-voltage load curve |
80% at 85 VAC; 100% at 100–264 VAC, 60 Hz |
| Working humidity |
20–90% RH, non-condensing |
| Storage temperature and humidity |
−40 to +85°C; 10–95% RH |
| Temperature coefficient |
±0.03%/°C, 0–45°C |
| Vibration |
10–500 Hz, 2 G; 10 minutes per cycle, 60 minutes along each X, Y and Z axis |
Above 2000 m, reduce the allowable ambient temperature by 3.5°C per 1000 m for fanless operation; the catalogue also specifies 5°C per 1000 m for fan-cooled installations. Maintain ventilation and evaluate the installation at its actual load and input voltage.
Safety and EMC
| Approved safety standards |
UL 62368-1; CB IEC 62368-1; EAC TP TC 004 |
| Safety design reference |
BS EN / EN 62368-1 |
| Withstand voltage |
Input–output: 3 kVAC; input–FG: 2 kVAC; output–FG: 0.5 kVAC |
| Isolation resistance |
100 MΩ at 500 VDC, 25°C and 70% RH |
| EMC emission |
BS EN / EN 55032 (CISPR 32), Class B; BS EN / EN 61000-3-2 and -3-3; EAC TP TC 020 |
| EMC immunity |
BS EN / EN 61000-4-2, -3, -4, -5, -6, -8 and -11; ENV 50204; BS EN / EN 55035 and 61000-6-1; EAC TP TC 020 |
Immunity is specified for the light-industry environment. This power supply is a component for installation in final equipment; the completed system must be checked for the applicable EMC requirements.
Mechanical Installation and Reference Mass
| Catalogue dimensions, L × W × H |
129 × 98 × 38 mm |
| Drawing case number |
903 |
| Drawing dimensional tolerance |
±1 mm |
| Mass, catalogue PACKING reference per unit |
450 g |
| Catalogue packing |
0.45 kg; 30 units / 14.5 kg / 0.95 CUFT |
| Minimum MTBF, Telcordia / MIL-HDBK-217F |
2868.4K / 495.8K hours |
| Warranty |
2 years |
Two bottom M3 holes marked L = 4 mm and three side M3 holes marked L = 6 mm; the drawing also marks 3.5 mm holes.
The enclosed supply is suitable for metallic or non-metallic system installations subject to the relevant insulation and protective-earth requirements. Follow the mounting drawing and installation manual, keep ventilation openings clear, and connect FG correctly.
The MTBF values use Telcordia SR-332 (Bellcore) and MIL-HDBK-217F at 25°C respectively. The unit has a power-on LED and undergoes a full-load burn-in test.
