The MEAN WELL ENC-240-48 is a fanless desktop battery charger with a default 57.6 V boost setting, 55.2 V float setting and 4 A constant-current charging output, rated at 230.4 W. Its 48 V model designation identifies the nominal voltage class, not the actual boost or float voltage. The three-stage charging profile supports DIP-selected presets and programming for the particular battery specification.
Product Datasheet
Download MEAN WELL ENC-240 Datasheet (PDF)
The ENC-240 section is on PDF pages 29, 30, 31, 32, 33, 34. Refer to the complete mechanical drawings and notes when planning installation.
Charging Output and Battery Selection
| Complete model |
ENC-240-48 |
| Nominal voltage class |
48 V |
| Default boost charge voltage |
57.6 V |
| Default float charge voltage |
55.2 V |
| Rated charging current |
4 A |
| Rated output power |
230.4 W |
| Programmable boost or float range |
36–60 V |
| Suggested battery capacity |
15–45 Ah |
| Typical battery leakage current |
Less than 1 mA |
| Typical efficiency |
93% |
The voltage range applies to programming Vboost or Vfloat with the SBP-001 smart battery charging programmer; it is not a separate continuously adjustable front-panel output. The listed battery-capacity range is a recommendation, not a substitute for checking the battery manufacturer’s maximum charging current.
The catalogue identifies flooded, gel and AGM lead-acid batteries, and lithium-ion batteries described as lithium iron and lithium manganese. Select a charging profile approved for the particular pack, chemistry and battery-management requirements. Modification of charger specifications may be needed; consult the battery supplier and MEAN WELL. A nominal voltage match alone does not establish compatibility.
Three-Stage Charging and DIP Presets
| DIP 1 OFF / DIP 2 OFF |
Default programmable: 57.6 V boost / 55.2 V float |
| DIP 1 ON / DIP 2 OFF |
Gel preset: 56 V boost / 54.4 V float |
| DIP 1 OFF / DIP 2 ON |
Flooded preset: 56.8 V boost / 53.6 V float |
| DIP 1 ON / DIP 2 ON |
AGM preset: 58 V boost / 54 V float |
| Default CC value for these curves |
4 A |
| Status indicator |
Orange: charging in stage 1 or 2; green: float in stage 3 |
Stage 1 supplies constant current while battery voltage rises to Vboost. Stage 2 holds Vboost while current falls. The published curve changes to stage 3 at 10% of the CC setting, reducing voltage to Vfloat. Green identifies the float stage rather than an independently measured state of charge for every battery chemistry.
To alter the default charging curve, use the MEAN WELL SBP-001 smart battery charging programmer with a personal computer. Select programming and interconnection accessories for this charger; the charger order number does not itself include the programmer or computer. The other three predefined profiles are selected with the two-position DIP switch.
Input and Power Factor
| Input range |
90–264 VAC or 127–370 VDC |
| AC frequency |
47–63 Hz |
| Typical AC input current |
2.5 A at 115 VAC; 1.25 A at 230 VAC |
| Active PFC, typical power factor |
PF >0.98 at 115 VAC and >0.95 at 230 VAC, at full load |
| Typical cold-start inrush current |
75 A at 230 VAC |
| Leakage current |
Less than 3.5 mA at 240 VAC |
The mechanical drawing shows an AC inlet, power switch and frame-grounded metal enclosure. Use the inlet and protective-earth arrangement shown in the product drawing. Input-current and efficiency figures are typical, under the stated catalogue test conditions.
Protection and Temperature Compensation
| Short circuit |
Output shutdown; re-power to recover. This mechanism is specified for a short circuit occurring after the charger has been turned on. |
| Overvoltage range |
62.1–72.9 V; output shuts down and latches off; re-power to recover |
| Overtemperature |
Output shutdown; automatic recovery after temperature falls |
| Reverse battery polarity |
Protection by an internal fuse |
| Battery under- and overvoltage |
Listed protection functions; battery-specific threshold suitability must be confirmed |
| Temperature compensation |
Built-in function using an NTC sensor |
The MCU-controlled dynamic overvoltage protection is approximately 115% of Vboost during constant-current and constant-voltage stages, and 115% of Vfloat during float charging. These protection levels do not replace the selected battery charging limits. Connect the NTC circuit to CN31 RTH+ and RTH− using the matching sensor assembly. No numerical temperature-compensation slope or battery under-/overvoltage cutoff is specified in these pages.
Cooling and Derating
| Cooling |
Fanless, free-air convection |
| Working temperature |
−30 to +70°C, subject to derating |
| Horizontal installation curve |
100% load from −30 to +50°C; reduce linearly to 60% at +70°C |
| AC input curve at 60 Hz |
90% load at 90 VAC; 100% at 100 VAC and from 100 to 264 VAC |
Allow free airflow around the charger and apply temperature and low-input restrictions together. The AC graph does not establish a separate DC-input derating curve. For this fanless model above 2000 m, reduce permissible ambient temperature by 3.5°C per additional 1000 m. This adjustment is not an unrestricted maximum-altitude rating.
Output Terminals and Programming Connector
| TB1 terminal assignment |
1 and 2: +V; 3 and 4: −V |
| TB1 wire cross-section |
0.5–4.0 mm²; the catalogue also specifies 12–20 AWG |
| TB1 stripping and tightening |
9 mm stripped length; 4.0 lb-in torque (0.4–0.5 N·m) |
| CN31 connector |
HRS DF11-6DP-2DS or equivalent |
| CN31 mating housing |
HRS DF11-6DS or equivalent |
| CN31 contacts |
HRS DF11-**SC or equivalent contact family |
| CN31 pins 1 and 2 |
1: Prog- +3.3V; 2: Prog- GND |
| CN31 pins 3 and 4 |
3: Prog- RX; 4: Prog- TX |
| CN31 pins 5 and 6 |
5: RTH+; 6: RTH− |
Use the pin orientation in the mechanical drawing rather than relying on a connector photograph. DF11-**SC is a contact-family notation containing a wildcard; select the complete contact suffix appropriate to the wire and assembly. CN31 programming pins are not presented as a general-purpose remote ON/OFF interface.
NTC Accessories and Mechanical Installation
| NTC sensor wire |
Accessory list quantity: 1; UL2468 24×2C marking; drawing shows 50 mm insulated length and 7 mm stripped ends |
| NTC mating wire |
Accessory list quantity: 1; UL1007 28 AWG; drawing shows 50 mm insulated length and 6 mm stripped ends |
| Body dimensions |
192 × 178 × 45.5 mm (L × W × H) |
| Case drawing |
Case No. 252; dimensional tolerance ±1 mm |
| Mounting callout |
Two M3 positions, marked 2-M3 L=5; 78 mm centre spacing |
| Catalogue unit weight |
1.23 kg (1230 g), catalogue packing reference per unit; not a measured net or shipping weight |
The NTC accessory drawings are on PDF page 34. The mating-wire drawing carries the HRS DF11-6DP-2DS or equivalent caption; use it together with the explicit CN31 mating-housing and contact table on page 33 when ordering a complete assembly. No independent sensor assembly order code is specified on these pages. Confirm the actual accessory supply contents.
The mounting centres are 47.5 mm from the indicated right-hand body edge, with the upper centre 50 mm from the top edge. The side view also marks a 4.3 mm projection beyond the 45.5 mm body dimension. Follow the complete drawing for inlet, output-terminal, LED, switch and cable clearances; do not obstruct convection cooling.
Environment, Safety and Reliability
| Working humidity |
20–95% RH, non-condensing |
| Storage conditions |
−40 to +85°C; 10–95% RH, non-condensing |
| Temperature coefficient |
±0.05%/°C over 0–50°C |
| Vibration |
10–500 Hz, 2 G, 10 minutes per cycle; 60 minutes along each X, Y and Z axis |
| Dielectric withstand |
Input–output: 3 kVAC; input–FG: 2 kVAC; output–FG: 0.5 kVAC |
| Insulation resistance |
100 MΩ for input–output, input–FG and output–FG, at 500 VDC, 25°C and 70% RH |
IEC 62368-1, UL 62368-1, EAC TP TC 004 and BSMI CNS 15598-1 approved; meets BS EN/EN 62368-1.
BS EN/EN 55032 (CISPR32) and FCC Part 15 (CISPR22), Class B for both conducted and radiated emissions. BSMI CNS 15936 is also listed for both. Harmonic current: BS EN/EN 61000-3-2. Voltage flicker: BS EN/EN 61000-3-3.
BS EN/EN 55024. The immunity table specifies ESD (61000-4-2) level 3, 8 kV air and level 2, 4 kV contact; radiated RF (4-3) level 2, 3 V/m; EFT/burst (4-4) level 2, 1 kV; surge (4-5) level 2, 1 kV line–line and level 3, 2 kV line–earth; conducted RF (4-6) level 2, 3 Vrms; and magnetic field (4-8) level 1, 1 A/m. For 61000-4-11, the table gives >95% dip for 0.5 periods, 30% dip for 25 periods, and >95% interruption for 250 periods.
Calculated MTBF: 1423.3 thousand hours minimum using Telcordia SR-332, or 155.9 thousand hours minimum using MIL-HDBK-217F at 25°C. These estimates are not a service-life guarantee. The manufacturer’s catalogue lists a three-year warranty.
Unless otherwise stated, measurements use 230 VAC, rated load and 25°C ambient. The charger is considered an independent unit, but EMC compliance of the final equipment must be reconfirmed. Confirm battery-specific settings before use.
