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Mean Well LOP-300-27 300W 4"×2" Low Profile Open Frame Power Supply 27V 6.7A

conventional 180W300W with 10.98CFM forced airhigh frequency up to 94%
SKU LOP-300-27
$71.41 USD
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Overview

LOP-300-27 is the 27V output model of this series: typical efficiency 93%.

The LOP-300 is a 300W highly reliable, energy-efficient, low-profile open frame type power supply. With a high power density of 37.5W/in³ within the standard size of 4" × 2", it features a universal input voltage range of 80~264VAC, making it suitable for global applications. The series offers a comprehensive selection of standard voltages, including 12V/15V/18V/24V/27V/30V/36V/48V/54V, and comes in a complete range of models. The main features of the LOP-300 include: low standby power (<0.5W), high efficiency (up to 94%), capable providing 180W under natural air cooling and 300W with an additional fan. It has a 150% @ 3 seconds peakload capacity, a wide operating temperature range of -40 to +80℃, compliance with OVCⅢ, suitable for Class Ⅰ (with FG) or Class Ⅱ (without FG) systems. The product has obtained multiple safety certifications, including 62368-1/60601-1/61558-1/60335-1, and is designed to meet 2xMOPP and extremely low touch leakage current <70 μ A, making it suitable for BF class medical devices. With high product safety and excellent EMC performance, it is versatile and applicable in various fields such as ITE, medical, industrial control, home automation and more. It is a cost-effective slim open frame type power supply.

Features

  • MEAN WELL Patent Number: ZL 202223277512.1
  • 4"×2" compact size with low profile (25.4mm)
  • 80~264Vac input with PFC, No load power consumption<0.5W
  • Global certificates in multi-fields (ITE 62368-1, Medical 60601-1, Household 60335-1, Industrial 61558-1/-2-16)
  • 150%peak load @ 3s
  • 180W convection, 300W with FAN 10.98CFM forced-cooled
  • Suitable for Class Ⅰ or Class Ⅱ installations
  • Over voltage category Ⅲ (OVC Ⅲ)
  • -40 ~ +80℃ wide range operation temperature
  • High efficiency up to 94%
  • Protections: Short circuit / Overload / Over voltage / Over temperature
  • Extremely low leakage current, 2 x MOPP, suitable for BF medical applications
  • Operating altitude up to 5000 meters
  • Built-in 12V/0.5A for external FAN
  • 3 years warranty

Specifications

LOP-300-27Specifications from the official datasheet (2026-09-02 edition)

OUT PUT

DC VOLTAGE
27V
CURRENT Peak(3sec.)
16.7A
CURRENT 10.98CFM
11.1A
CURRENT Convection
6.7A
RATED POWER Peak(3sec.)
450W
RATED POWER 10.98CFM
299.7W
RATED POWER Convection
180.9W
RIPPLE & NOISE (max.)Note.2
200mVp-p
VOLTAGE ADJ. RANGE (MAIN OUTPUT)
25.6 ~ 28.4V
VOLTAGE TOLERANCENote.3
±1.0%
LINE REGULATION
±0.5%
LOAD REGULATION
±1.0%
SETUP, RISE TIME
1000ms, 30ms/230Vac 1500ms, 30ms/115Vac at full load
HOLD UP TIME (Typ.)
16ms@180W load , 8ms@300W load

INPUT

VOLTAGE RANGENote.4
80 ~ 264Vac 113 ~ 370Vdc
FREQUENCY RANGE
47 ~ 63Hz
POWER FACTOR
PF>0.95/230Vac PF>0.98/115Vac at full load
EFFICIENCY (Typ.)
93%
AC CURRENT (Typ.)
3.5A/115Vac 1.8A/230Vac
INRUSH CURRENT (Typ.)
COLD START 40A/115Vac 80A/230Vac
LEAKAGE CURRENT
ClassⅠ: Earth leakage current < 500 μA (rms) @ 264V ac , touch current < 70μA (rms) @ 264V ac ClassⅡ: Touch current < 100 μA (rms) @ 264V ac

PROTECTION

OVERLOAD
105 ~ 180% rated output power, Protection type : Hiccup after 3 sec, recovers automatically(3 sec) after fault condition is removed
OVER VOLTAGE
29.7 ~ 35.1V Protection type : Shut down o/p voltage, re-power on to recover
OVER TEMPERATURE
Protection type : Shut down o/p voltage, recovers automatically after temperature goes down or re-power on to recover

FUNCTION

EXTERNAL FAN SUPPLY
12V@0.5A for driving a fan (10.98CFM) / 12V@0.1A without fan cooling ; Tolerance -20% ~ +15% at main output 20% rated current

ENVIRONMENT

WORKING TEMP.
-40 ~ +80℃ (Refer to "Derating Curve")
WORKING HUMIDITY
20 ~ 90% RH non-condensing
STORAGE TEMP., HUMIDITY
-40 ~ +85℃, 10 ~ 95% RH non-condensing
TEMP. COEFFICIENT
±0.03%/℃ (0 ~ 50℃)
VIBRATION
10 ~ 500Hz, 2G 10min./1cycle, 60min. each along X, Y, Z axes

SAFETY & EMC

SAFETY STANDARDSNote.5
CB IEC62368-1, IEC60335-1, IEC61558-1/-2-16, IEC60601-1; TUV BS EN/EN62368-1, BS EN/EN60335-1, BS EN/EN61558-1/-2-16, BS EN/EN60601-1(3.2 Version); UL UL62368-1, ANSI / AAMI ES60601-1(3.2 Version) ; CCC GB4943.1 ; RCM AS/NZS 61558-1/-2-16; EAC TPTC 004 approved.
ISOLATION RESISTANCE
Primary-Secondary: 2xMOPP, Primary-Earth:1xMOPP, Secondary-Earth:1xMOPP
OVER VOLTAGE CATEGORY
IEC/EN 61558-1/-2-16(OVC Ⅲ, altitude up to 2000M ) IEC/EN/UL 62368-1 (OVC Ⅱ, altitude up to 5000M ) IEC/EN 60335-1 (OVC Ⅱ, altitude up to 5000M ) IEC/EN 60601-1 (OVC Ⅱ, altitude up to 4000M )
PROTECTIVE EXTRA-LOW VOLTAGE
IEC/EN61558-2-16 (SELV, 12~48V ) IEC/EN/UL 62368-1 (SELV / ES1, 12~48V )
WITHSTAND VOLTAGE
I/P-O/P:4KVac I/P-FG:2KVac O/P-FG:1.5KVac
ISOLATION RESISTANCE
I/P-O/P, I/P-FG, O/P-FG:100M Ohms / 500VDC / 25℃/ 70% RH
EMC EMISSION
ParameterStandardTest Level
Conducted & RadiatedBS EN/EN55032(CISPR32) BS EN/EN55011(CISPR11)ClassⅠ: Class B , Class Ⅱ: Class A
Conducted & RadiatedBS EN/EN55014(CISPR32)ClassⅠ: Class B
Harmonic CurrentBS EN/EN61000-3-2Class A
Voltage FlickerBS EN/EN61000-3-3
EMC IMMUNITY

BS EN/EN55035,BS EN/ EN61000-6-2

ParameterStandardTest Level
ESDBS EN/EN61000-4-2Level 4, 15KV air; Level 4, 8KV contact
Radiated SusceptibilityBS EN/EN61000-4-3Level 3, 10V/m( 80MHz~2.7GHz ) Table 9, 9~28V/m( 385MHz~5.78GHz )
EFT/BurestBS EN/EN61000-4-4Level 3, 2KV
SurgeBS EN/EN61000-4-5Level 4, 4KV/Line-FG; 2KV/Line-Line
ConductedBS EN/EN61000-4-6Level 3, 10V
Magnetic FieldBS EN/EN61000-4-8Level 4, 30A/m
Voltage Dips and interruptionsBS EN/EN61000-4-11>95% dip 0.5 periods, 100% dip 1 periods, 30% dip 25 periods, >95% interruptions 250 periods

OTHERS

MTBF
2805.6K hrs min. Telcordia SR-332 (Bellcore) ; 384.4K hrs min. MIL-HDBK-217F (25℃)
DIMENSION
101.6*50.8* 25.4mm (L*W*H)
PACKING
0.21Kg; 36pcs/10Kg/0.95CUFT
Test conditions and notes5
  1. 1. All parameters NOT specially mentioned are measured at 230VAC input, rated load and 25℃ of ambient temperature.
  2. 2. Ripple & noise are measured at 20MHz of bandwidth by using a 12" twisted pair-wire terminated with a 0.1 μF & 47 μF parallel capacitor.
  3. 3. Tolerance : includes set up tolerance, line regulation and load regulation.
  4. 4. Derating may be needed under low input voltages. Please check the derating curve for more details.
  5. 5. The power supply is considered a component which will be installed into a final equipment. All the EMC tests are been executed by mounting the unit on a 360mm*360mm metal plate with 1mm of thickness. The final equipment must be re-confirmed that it still meets EMC directives. For guidance on how to perform these EMC tests, please refer to “EMI testing of component power supplies.” (as available on https://www.meanwell.com//Upload/PDF/EMI_statement_en.pdf)

Technical drawings

LOP-300-27 LOP-300 series (2)
LOP-300 series (2)
LOP-300-27 Derating Curve
Derating Curve
LOP-300-27 Output Derating VS Input Voltage
Output Derating VS Input Voltage
LOP-300-27 Mechanical Specification
Mechanical Specification
LOP-300-27 Mechanical Specification (2)
Mechanical Specification (2)
LOP-300-27 Installation Manual
Installation Manual

Typical applications

  • Industrial automation machinery/ control system
  • Security system
  • Mechanical and electrical equipment
  • Electronic instruments, equipments or apparatus
  • Network equipment
  • Telecom devices
  • Power sourcing equipment of PoE
  • Home automation
  • Medical devices

Downloads

FAQ

What is the main use case for the Mean Well LOP-300-27?

The LOP-300-27 is a 300W low profile open frame AC-DC power supply designed for embedded OEM equipment and space-constrained systems. Its 27V output and 4 x 2 inch footprint make it a fit for industrial, medical, household, and ITE applications that need a compact internal power solution.

What output does the LOP-300-27 provide?

This model provides a single 27V DC output rated at 6.7A (180.9W) with convection cooling, or 11.1A (299.7W) with a 10.98CFM fan. It is part of Mean Well's LOP-300 series and is intended for applications that specifically require a 27V output version.

How compact is the Mean Well LOP-300-27?

The LOP-300-27 measures 101.6 x 50.8 x 25.4 mm, which corresponds to a 4 x 2 inch form factor with a low 25.4 mm profile. This compact size helps when enclosure height and board space are limited.

Can the LOP-300-27 operate in demanding temperature environments?

Yes. This power supply is rated for operation from -40°C to +80°C, subject to the manufacturer's derating conditions. That wide operating range makes it suitable for equipment exposed to wide ambient temperature variation.

What certifications and standards does the LOP-300-27 support?

The LOP-300-27 is designed to meet multiple global safety standards across ITE, medical, household, and industrial categories, including IEC/EN/UL 62368-1, IEC/EN 60601-1, and IEC/EN 61558-1/-2-16. It also offers 2 x MOPP primary-to-secondary isolation and touch current below 100μA (Class II).

What input range does the Mean Well LOP-300-27 accept?

This model accepts a wide universal input range of 80 to 264VAC, and it also supports 113 to 370VDC input. It includes active power factor correction, with published full-load power factor values above 0.95 at 230VAC and above 0.98 at 115VAC.

Does the LOP-300-27 include protection and peak load capability?

Yes. The unit includes protection for overload, overvoltage, and overtemperature. Mean Well also specifies 150% peak load capability for 3 seconds, which can help with brief power demand spikes in the host equipment.

Is the LOP-300-27 suitable for systems that need higher cooling-assisted output?

Yes. Mean Well rates the LOP-300 series at 180W under convection cooling and up to 300W with 10.98 CFM forced-air cooling. This gives designers flexibility when comparing passive versus fan-assisted thermal designs around the same power platform.

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Mean Well LOP-300-27 300W 4"×2" Low Profile Open Frame Power Supply 27V 6.7A
Mean Well

Mean Well LOP-300-27 300W 4"×2" Low Profile Open Frame Power Supply 27V 6.7A

$71.41 USD

LOP-300-27 is the 27V output model of this series: typical efficiency 93%.

The LOP-300 is a 300W highly reliable, energy-efficient, low-profile open frame type power supply. With a high power density of 37.5W/in³ within the standard size of 4" × 2", it features a universal input voltage range of 80~264VAC, making it suitable for global applications. The series offers a comprehensive selection of standard voltages, including 12V/15V/18V/24V/27V/30V/36V/48V/54V, and comes in a complete range of models. The main features of the LOP-300 include: low standby power (<0.5W), high efficiency (up to 94%), capable providing 180W under natural air cooling and 300W with an additional fan. It has a 150% @ 3 seconds peakload capacity, a wide operating temperature range of -40 to +80℃, compliance with OVCⅢ, suitable for Class Ⅰ (with FG) or Class Ⅱ (without FG) systems. The product has obtained multiple safety certifications, including 62368-1/60601-1/61558-1/60335-1, and is designed to meet 2xMOPP and extremely low touch leakage current <70 μ A, making it suitable for BF class medical devices. With high product safety and excellent EMC performance, it is versatile and applicable in various fields such as ITE, medical, industrial control, home automation and more. It is a cost-effective slim open frame type power supply.

Features

  • MEAN WELL Patent Number: ZL 202223277512.1
  • 4"×2" compact size with low profile (25.4mm)
  • 80~264Vac input with PFC, No load power consumption<0.5W
  • Global certificates in multi-fields (ITE 62368-1, Medical 60601-1, Household 60335-1, Industrial 61558-1/-2-16)
  • 150%peak load @ 3s
  • 180W convection, 300W with FAN 10.98CFM forced-cooled
  • Suitable for Class Ⅰ or Class Ⅱ installations
  • Over voltage category Ⅲ (OVC Ⅲ)
  • -40 ~ +80℃ wide range operation temperature
  • High efficiency up to 94%
  • Protections: Short circuit / Overload / Over voltage / Over temperature
  • Extremely low leakage current, 2 x MOPP, suitable for BF medical applications
  • Operating altitude up to 5000 meters
  • Built-in 12V/0.5A for external FAN
  • 3 years warranty

Typical applications

  • Industrial automation machinery/ control system
  • Security system
  • Mechanical and electrical equipment
  • Electronic instruments, equipments or apparatus
  • Network equipment
  • Telecom devices
  • Power sourcing equipment of PoE
  • Home automation
  • Medical devices
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