MEAN WELL NPB-120-12TB is an adjustable NPB-120 AC/DC battery charger for the 12 V nominal battery class, with TB terminal block output. Default boost and float voltages are 14.4 V and 13.8 V, and the typical charging current is 6.8 A. Maximum output power is 103.4 W, subject to input-voltage and temperature derating.
Product Datasheet
Download MEAN WELL NPB-120 Datasheet (PDF)
The NPB-120 section is on PDF pages 1, 2, 3, 4, 5, 6, 7. Refer to the complete mechanical drawings and notes when planning installation.
Model and Charging Output
| Full ordering model |
NPB-120-12TB; NPB-120 series, 12 V nominal battery class, TB terminal block output. |
| Default boost charge voltage |
14.4 V. |
| Default float charge voltage |
13.8 V. |
| Default charging current |
6.8 A, typical catalogue output-current setting. |
| Max. output power |
103.4 W; input-voltage and temperature derating apply. |
| Voltage adjustment |
10.5–15.2 V using the front Vo Adj. control. |
| Charging-current adjustment |
3.4–6.8 A (50–100%) using the front Io Adj. control. |
| Suggested battery capacity |
20–90 Ah; confirm the battery manufacturer’s maximum charging current and charging profile. |
| Typical efficiency |
87% for this TB configuration at the stated default test conditions. |
| Typical leakage from battery |
Less than 1 mA. |
The 12 V designation is the nominal battery class, not the actual boost or float charging voltage. Select the charging voltage and current for the specific battery; voltage adjustment does not increase the current limit or maximum available power.
Charging Modes and Status
| Factory charging mode |
Three-stage charging; the front 3 Stage 2 switch selects two-stage or three-stage operation. |
| Two-stage profile |
Constant current followed by constant voltage at Vfloat; the catalogue diagram marks 10% of CC at the red-to-green transition. |
| Three-stage profile |
Constant current, constant voltage at Vboost, then float at Vfloat. The diagram marks 10% of CC at the transition to float. |
| Status LED |
Red during charging stages 1 and 2; green at stage 3 float or when the battery is full. |
The catalogue describes two-stage charging for lithium batteries such as lithium iron and lithium manganese types, and three-stage charging for lead-acid flooded, gel and AGM batteries. Battery specifications may require different settings; confirm compatibility with the battery manufacturer and MEAN WELL.
Input and Protection
| Input voltage / frequency |
90–264 VAC or 127–370 VDC; AC frequency 47–63 Hz. |
| AC connection |
Class I design with FG; IEC 320-C14 inlet and AC switch. |
| Power factor / inrush control |
Built-in active PFC and active inrush-current limiting; typical PF >0.98 at 115 VAC and >0.92 at 230 VAC, full load. |
| Typical AC input current |
1.5 A at 115 VAC; 0.8 A at 230 VAC. |
| Typical cold-start inrush |
55 A at 230 VAC. |
| Input leakage current |
Less than 0.75 mA at 240 VAC. |
| Power consumption with AC switch OFF |
Less than 0.15 W. |
| Short circuit |
Constant-current limiting; shutdown after 5 seconds, then re-power to recover. This protection description applies to a short circuit occurring after the charger is turned on. |
| Overvoltage |
16–20 V; output shutdown and latch-off, followed by re-powering to recover. |
| Overtemperature |
Hiccup operation; automatic recovery after the temperature decreases. |
| Reverse battery polarity |
Protection by opening the internal fuse. |
Cooling, Environment and Load Limits
| Cooling |
Fanless free-air convection. |
| Working temperature |
-30°C to +70°C with derating; horizontal installation for the plotted thermal curves. |
| Horizontal temperature curve |
100% load from -30°C to +45°C. The plotted points are 80% at +50°C, 65% at +60°C and 40% at +70°C. |
| Input-voltage load curve |
At 60 Hz: 90% load at 90 VAC, reaching 100% at 100 VAC and remaining at 100% through 264 VAC, before temperature derating. |
| Working humidity |
20–95% RH, non-condensing. |
| Storage temperature / humidity |
-40°C to +85°C; 10–95% RH, non-condensing. |
| Temperature coefficient |
±0.05%/°C from 0°C to +45°C. |
| Vibration |
10–500 Hz, 2 G; 10-minute cycle, 60 minutes each along X, Y and Z. |
Apply input-voltage and temperature limits together. Keep the charger’s ventilation path clear; the operating-temperature range is not a full-power rating at every temperature.
Dimensions, Connections and Mounting
| Body dimensions, L × W × H |
182.7 × 96 × 49 mm; case PS-120F. Drawing dimensions are in mm with ±1 mm tolerance. |
| Standard output connection |
DT-66-B11W-02 or equivalent, marked 300 V / 40 A as a terminal-component rating. Viewed from the output front: left terminal +V, right terminal −V. Use the charger limits above for the output rating. |
| Output cable |
Direct output terminal block; the cable-version length does not apply. |
| Catalogue unit packing reference |
1300 g per unit. The separate carton entry is 10 pieces / 14 kg / 1.13 CUFT. |
| Optional mounting bracket |
PGG2MHS012D, ordered separately. The installation uses four brackets per charger; this is an installation quantity, not a stated sales-pack quantity. |
| Bracket installation drawing |
The diagram uses M3 × 4 screws and marks four M3 holes with L=5. The side view marks 106.4 mm between mounting positions and 44.65 mm from the case edge to the first position. See physical catalogue page 6. |
Use the indicated positive and negative output connections. The mounting-bracket listing does not specify a separate supplied fastener set; confirm the required mounting hardware with the order.
Factory-Customized DC Connector Options
| R7B |
Locking male mini-DIN 4-pin; KYCON KPPX-4P equivalent. Pins 1/4 +Vo and 2/3 −Vo; output current <7 A. |
| XLR4 |
4-pin XLR; pins 1/2 +Vo and 3/4 −Vo. Output current <10 A. |
| D3P |
DIN 3-pin; pin 1 +Vo, pins 2/3 −Vo; output current <7 A. |
| D2P |
DIN 2-pin; pin 1 −Vo, pin 2 +Vo; output current <5 A. |
| INL3 |
DIN 3-pin DC connector; N +Vo, L −Vo; output current <10 A. These are DC plug markings. |
| C4P |
AMP 1-480702-0 (6.35 mm) equivalent; pins 1/2 +Vo and 3/4 −Vo; output current <7 A. FG is not connected to this output connector. |
These DC alternatives are available through customization and are separate from this TB standard configuration. Match voltage, polarity and the actual selected charging current to the strict connector limits shown; a connector option does not increase available charger power or current.
Safety, EMC and Reliability
| Catalogue safety scope |
The catalogue lists CB IEC 62368-1 / IEC 60335-1/2-29, Dekra BS EN/EN 62368-1 / BS EN/EN 60335-1/2-29, UL 62368-1, AS/NZS 60335-1/2-29, EAC TP TC 004 and BSMI CNS 15598-1. The cover identifies this configuration as a UL recognized component. |
| 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. |
| Emission and mains disturbance |
BS EN/EN 55032 (CISPR 32), 55014-1 and CNS 15936: conducted/radiated Class B. Harmonic current: BS EN/EN 61000-3-2 Class A; flicker: 61000-3-3. |
| Immunity framework |
BS EN/EN 55014-2, 55024 and 55035. |
| ESD / RF / EFT |
IEC/EN 61000-4-2: 8 kV air, level 3; 4 kV contact, level 2. -4-3: 3 V/m, level 2. -4-4: 1 kV, level 2. |
| Surge / conducted RF / magnetic field |
IEC/EN 61000-4-5: 1 kV line–line, level 2; 2 kV line–earth, level 3. -4-6: 3 Vrms, level 2. -4-8: 1 A/m, level 1. |
| Voltage dips / interruptions |
IEC/EN 61000-4-11: >95% dip for 0.5 period; 30% dip for 25 periods; >95% interruption for 250 periods. |
| MTBF references |
1895.4 thousand hours minimum, Telcordia TR/SR-332 (Bellcore); 225.8 thousand hours minimum, MIL-HDBK-217F at 25°C. |
| Catalogue warranty |
3 years. |
These are the applicable catalogue statements for the charger. The completed equipment and its installation must be rechecked for EMC compliance. Unless otherwise specified, parameters are measured at 230 VAC input, rated load and 25°C ambient.
