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Mean Well PWM-40-12 Power Supply 40W 12V - Dimmable 3.34A

PWM style outputfully isolated plastic caseIP67Class II design without FGbuilt-in 3 in 1 dimming

SKU PWM-40-12

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PWM-40-12

PWM-40-12 Dimmable In stock

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PWM-60-12DA DALI Backorder

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Product variants

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Overview

PWM-40-12 is the 12V output model of this series: rated current 3.34A, rated power 40.08W, typical efficiency 86%.

PWM-40 series is a 40W LED AC/DC LED driver featuring the constant voltage mode with PWM style output, which is able to maintain the color temperature and the brightness homogeneity when driving all kinds of LED strips. PWM-40 operates from 90～305VAC and offers models with different rated voltage ranging between 12V and 48V. Thanks to the high efficiency up to 90%, with the fanless design, the entire series is able to operate for -40℃ ~ +85℃ case temperature under free air convection. The entire series is rated with IP67 ingress protection level and is suitable to work for dry, damp or wet locations. PWM-40 is equipped with dimming function that varies the duty cycle of the output, providing great flexibility for LED strips applications.

Features

Constant Voltage PWM style output with frequency 1.47kHz
Plastic housing with class II design
Built-in active PFC function
Class 2 power unit
No load power consumption <0.5W
Fully encapsulated with IP67 level
Function: 3 in 1 dimming (dim-to-off)
Typical lifetime>50000 hours
5 years warranty

Specifications

PWM-40-12Specifications from the official datasheet (2026-02-04 edition)

OUTPUT

DC VOLTAGE: 12V
RATED CURRENT: 3.34A
RATED POWER: 40.08W
DIMMING RANGE: 0 ~ 100%
PWM FREQUENCY (Typ.): 1.47kHz
SETUP, RISE TIME^Note.2: 500ms, 80ms 115VAC / 230VAC
HOLD UP TIME (Typ.): 16ms/115VAC or 230VAC

INPUT

VOLTAGE RANGE^Note.3: 90 ~ 305VAC 127 ~ 431VDC (Please refer to "STATIC CHARACTERISTIC" section)
FREQUENCY RANGE: 47 ~ 63Hz
POWER FACTOR (Typ.): PF>0.97/115VAC, PF>0.95/230VAC, PF>0.92/277VAC @ full load (Please refer to "POWER FACTOR (PF) CHARACTERISTIC" section)
TOTAL HARMONIC DISTORTION: THD< 20%(@load≧60%/115VAC, 230VAC; @load≧75%/277VAC) (Please refer to "TOTAL HARMONIC DISTORTION" section)
EFFICIENCY (Typ.): 86%
AC CURRENT (Typ.): 0.6A / 115VAC 0.3A / 230VAC 0.25A / 277VAC
INRUSH CURRENT (Typ.): COLD START 50A(twidth=270μs measured at 50% Ipeak) at 230VAC; Per NEMA 410
MAX. NO. of PSUs on 16A CIRCUIT BREAKER: 9 units (circuit breaker of type B) / 16 units (circuit breaker of type C) at 230VAC
LEAKAGE CURRENT: <0.25mA / 277VAC
NO LOAD POWER CONSUMPTION: <0.5W

PROTECTION

OVERLOAD: 108 ~ 130% rated output power Hiccup mode, recovers automatically after fault condition is removed
SHORT CIRCUIT: Shut down o/p voltage, re-power on to recover
OVER VOLTAGE: 15 ~ 17V Shut down o/p voltage, re-power on to recover
OVER TEMPERATURE: Shut down o/p voltage, re-power on to recover

ENVIRONMENT

WORKING TEMP.: Tcase=-40 ~ +85℃ (Please refer to " OUTPUT LOAD vs TEMPERATURE" section)
MAX. CASE TEMP.: Tcase=+85℃
WORKING HUMIDITY: 20 ~ 95% RH non-condensing
STORAGE TEMP., HUMIDITY: -40 ~ +80℃, 10 ~ 95% RH
TEMP. COEFFICIENT: ±0.03%/℃ (0 ~ 50℃)
VIBRATION: 10 ~ 500Hz, 5G 12min./1cycle, period for 72min. each along X, Y, Z axes

SAFETY & EMC

SAFETY STANDARDS^Note.5: UL8750( type "HL" ), UL879( for 12V,24V only), CSA C22.2 No. 250.13-12; ENEC BS EN/EN61347-1, BS EN/EN61347-2-13 independent,BS EN/EN62384, IP67,BIS IS15885( for 12V,24V only), EAC TP TC 004, GB/T19510.1,GB/T19510.213 approved; Design refer to BS EN/EN60335-1
WITHSTAND VOLTAGE: I/P-O/P:3.75KVAC
ISOLATION RESISTANCE: I/P-O/P:100M Ohms / 500VDC / 25℃/ 70% RH
EMC EMISSION^Note.6: Compliance to BS EN/EN55015, BS EN/EN61000-3-2 Class C (@load≧60%) ; BS EN/EN61000-3-3, GB/T 17743, GB17625.1, EAC TP TC 020
EMC IMMUNITY: Compliance to BS EN/EN61000-4-2,3,4,5,6,8,11; BS EN/EN61547, light industry level (surge immunity Line-Line 2KV),EAC TP TC 020

OTHERS

MTBF: 2625.4K hrs min. Telcordia SR-332 (Bellcore) ; 226.4K hrs min. MIL-HDBK-217F (25℃)
DIMENSION: 150*53*35mm (L*W*H)
PACKING: 0.49Kg;30pcs/15.7Kg/1.0CUFT

Test conditions and notes8

1. All parameters NOT specially mentioned are measured at 230VAC input, rated current and 25℃ of ambient temperature.
2. De-rating may be needed under low input voltages. Please refer to “STATIC CHARACTERISTIC” sections for details.
3. Length of set up time is measured at first cold start. Turning ON/OFF the driver may lead to increase of the set up time.
4. The driver is considered as a component that will be operated in combination with final equipment. Since EMC performance will be affected by the complete installation, the final equipment manufacturers must re-qualify EMC Directive on the complete installation again. (as available on https://www.meanwell.com//Upload/PDF/EMI_statement_en.pdf)
5. This series meets the typical life expectancy of >50,000 hours of operation when Tcase, particularly tc point (or TMP, per DLC), is about 75℃ or less.
6. Please refer to the warranty statement on MEAN WELL's website at http://www.meanwell.com
7. The ambient temperature derating of 3.5℃/1000m with fanless models and of 5℃/1000m with fan models for operating altitude higher than 2000m(6500ft).
8. For any application note and IP water proof function installation caution, please refer our user manual before using. https://www.meanwell.com/Upload/PDF/LED_EN.pdf

Technical drawings

PWM-40-12 DIMMING OPERATION — DIMMING OPERATION

PWM-40-12 ◎ Applying additive resistance — ◎ Applying additive resistance

PWM-40-12 OUTPUT LOAD vs TEMPERATURE — OUTPUT LOAD vs TEMPERATURE

PWM-40-12 STATIC CHARACTERISTIC — STATIC CHARACTERISTIC

PWM-40-12 TOTAL HARMONIC DISTORTION — TOTAL HARMONIC DISTORTION

PWM-40-12 Mechanical Specification — Mechanical Specification

PWM-40-12 Recommend Mounting Direction — Recommend Mounting Direction

PWM-40-12 ◎Connection for Blank-type — ◎Connection for Blank-type

Typical applications

LED strip lighting
Indoor LED lighting
LED decorative lighting
LED architecture lighting
Type "HL" for use in Class I, Division 2 hazardous (Classified) location.

Downloads

Certificates5

UL Certificate (PWM-40)(EN) PDF Download

CB Certificate (PWM-40)(EN) PDF Download

EMC Certificate (PWM-40)(EN) PDF Download

ENEC Certificate (PWM-40)(EN) PDF Download

ErP Certificate (PWM-40)(EN) PDF Download

Test reports1

Test Report(PWM-40-12)(EN) PDF Download

Catalogues1

Mean Well LED Driver Catalog PDF Download

FAQ

Can I use the PWM-40-12 to power 12V LED strip lighting outdoors?

Yes. The PWM-40-12 is rated IP67, meaning it is fully protected against dust and can withstand temporary immersion in water, making it suitable for outdoor and wet-location LED strip installations. Its operating range of -40°C to +85°C also covers most outdoor climates.

How much 12V LED strip can the PWM-40-12 drive?

The PWM-40-12 delivers a maximum of 40W at 12V. To find the maximum strip length, divide 40W by your strip's rated watts per meter — for example, a 10W/m strip allows up to 4 meters. Always check your specific strip's rated power per meter before finalizing the run length.

Is the PWM-40-12 suitable for dimmable LED sign or display lighting?

Yes. The PWM-40-12 features built-in 3-in-1 dimming, supporting 0–10V, PWM signal, and resistance dimming methods. This makes it well suited for dimmable 12V LED signage, channel letter lighting, and display case illumination.

Can I use the PWM-40-12 in an enclosed or weatherproof fixture?

Yes. The PWM-40-12 uses a fully isolated plastic case with a Class II design that requires no earth ground (FG), so it can be installed inside sealed or non-metallic enclosures. The IP67 housing also allows direct exposure to moisture without an additional enclosure.

Is the PWM-40-12 appropriate for powering 12V landscape or pathway lighting?

Yes. The IP67 rating and -40°C to +85°C operating temperature make the PWM-40-12 a practical choice for buried or surface-mounted 12V landscape and pathway lighting applications. Its 40W capacity can supply multiple low-wattage fixtures on a shared circuit.

How does the PWM-40-12 compare to other wattage options in the PWM series?

The PWM-40-12 provides 3.34A at 12V. Other wattage options in the PWM series include 60W, 90W, 120W, and 200W models, available in 12V, 24V, 36V, and 48V variants. Choose based on total load wattage.

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Model	Power	Voltage	Current	IP Rating
Mean Well PWM-40-24 Power Supply 40W 24V - Dimmable 1.67A	40.08W	24V	1.67A	IP67	View
Mean Well PWM-40-48 Power Supply 40W 48V - Dimmable 840mA	40.32W	48V	0.84A	IP67	View
Mean Well PWM-40-36 Power Supply 40W 36V - Dimmable 1.12A	40.32W	36V	1.12A	IP67	View

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