LG 55UM3DG (Discontinued) · Replacements in Qatar

Name: LG 55UM3DG 55-inch UHD Digital Signage Display
Brand: LG
SKU: lg-55um3dg
Availability: Discontinued

Overview

The LG 55UM3DG is a 55-inch UHD signage display with a 3,840 x 2,160 IPS panel, 350 nits typical brightness, IP5x dust protection and a built-in speaker. The manufacturer has discontinued this model, so SmartRooms Qatar can quote a current equivalent or a compatible replacement. It suits indoor hotel lobbies, school corridors and reception areas in Qatar that need slim, long-running screens.

What the LG 55UM3DG is and why it matters

The LG 55UM3DG is a 55-inch UHD signage display from the UM3D series, built for indoor public and commercial spaces where content must stay sharp through long daily running hours. Its 3,840 x 2,160 IPS panel carries four times the pixel count of Full HD, so text, maps and product images keep their detail at close range. The manufacturer has discontinued this model and its 55UM3DG-B variant. This page is written for organisations that already operate one, buyers comparing it with newer displays, and anyone who needs a current replacement.

Panel performance and daily running

The panel delivers 350 cd/m² typical brightness, a 1,100:1 contrast ratio and a 178 x 178 degree viewing angle. An 8 ms response time (G to G) and a 3% haze surface treatment keep moving content readable from the side. The display can be installed in portrait or landscape. The typical panel life is 50,000 hours, and the specification sheet rates operation at 18 hours a day across seven days.

Mounting, bezel and tilt planning

The frame measures 9.9 mm on the top, left and right and 14.4 mm at the bottom, which keeps multi-screen layouts tidy. The bare monitor measures 1,234.4 x 720.9 x 39.9 mm, and the head weighs 19.0 kg, or 19.6 kg with the stand. It uses a 300 x 300 mm VESA pattern. A tilt of up to 15 degrees is supported within 30°C and 50% humidity, which helps with screens mounted above eye level.

Choose the wall bracket (LSW350B) or stand (ST-653T) with your quotation
Confirm the wall can carry the 19.6 kg head with stand

Connectivity, software and built-in features

Three HDMI inputs with HDCP 2.2 and a USB 2.0 Type A port handle content feeds, while RS232C in and out lets a control system manage the screen. The built-in speaker helps in small rooms without external audio. The display runs LG webOS on a Quad Core SoC, so it can play content without a separate media player, but it is not compatible with OPS modules. SuperSign CMS, SuperSign Control and Control+ are listed with the unit, and external sensors such as GPIO, NFC/RFID and temperature sensors connect via USB.

Where it fits in Qatar

In a hotel lobby in West Bay, a screen behind the front desk can show welcome messages and wayfinding through the working day. A university building in Education City can use corridor screens for timetables and event notices. A government office in Msheireb can pair the panel with a Cisco-compatible meeting room so teams in Doha and abroad share one display. Each location needs an indoor, air-conditioned position, because the operating range is 0°C to 40°C, well below the 45°C-plus heat of a Doha summer.

What to plan before you order

Room temperature and humidity within 0°C to 40°C and 10% to 80%
Wall structure and a 300 x 300 mm VESA pattern for the mounting point
Power at 100-240V~, 50/60Hz, typical 95 W and maximum 140 W
Tilt angle and viewing height at the installation spot

SmartRooms Qatar offers a free site survey to check the wall, room temperature and power point before the unit is fixed, and quotations are usually provided within one working day. Send your room details and quantity, and request a quote for this model or a current equivalent.

Highlights

3,840 x 2,160 UHD IPS panel with 350 nits typical brightness
Portrait and landscape operation supported
IP5x dust protection and 9.9 mm side bezels
Three HDMI inputs with HDCP 2.2 and RS232C control
Built-in speaker and webOS without a separate media player
Up to 15 degree tilt within 30°C; 100-240V power supply

Estimated timeline

Quotation within 1 working day · delivery timing depends on stock availability, and we confirm it with your quotation.

Specifications

42 specifications · Source: manufacturer · checked Oct 2026

PANEL12

Screen Size: 55"
Panel Technology: IPS
Aspect Ratio: 16 : 9
Native Resolution: 3,840 x 2,160 (UHD)
Brightness(Typ.,cd/m²): 350
Contrast Ratio: 1,100:1
Viewing Angle (H x V): 178 x 178
Response Time: 8ms(G to G)
Surface Treatment (Haze): Haze 3%
Life time (Typ.): 50,000 Hrs
Operation Hours (Hours / Day): 18 / 7
Portrait / Landscape: Yes / Yes

CONNECTIVITY3

Input: HDMI (3, HDCP 2.2), USB 2.0 Type A
Output: Audio (Off/Fixed/Variable)
External Control: RS232C In/Out (4Pin Phone-jack)

MECHANICAL SPECIFICATION10

Bezel Color: Black
Bezel Width: 9.9 mm (T/R/L), 14.4 mm (B)
Weight (Head): 19.0 kg
Weight (Head+Stand): 19.6 kg
Packed Weight: 24.2 kg
Monitor Dimension (W × H × D): 1,234.4 x 720.9 x 39.9 mm
Monitor incl. Stand Dimensions (W x H x D): 1234.4 x 770.7 x 290.0 mm
Carton Dimensions (W × H × D): 1,360.0 x 835.0 x 175.0 mm
Handle: No
VESA™ Standard Mount Interface: 300 x 300

SPECIAL FEATURE2

Tilt (Facedown): Max. 15º *In conditions within 30ºC temperature, 50% humidity
IP Rating: IP5x

ENVIRONMENT CONDITIONS2

Operation Temperature: 0°C to 40°C
Operation Humidity: 10 % to 80 %

POWER2

Power Supply: 100-240V~, 50/60Hz
Power Type: Built-In Power

POWER CONSUMPTION2

Typ. / Max.: 95W / 140W
Smart Energy Saving: 70W

CERTIFICATION3

Safety: CB / NRTL
EMC: FCC Class “A” / CE / KC
ErP / Energy Star: Yes (EU Only) / Yes (Energy Star 8.0)

MEDIA PLAYER COMPATIBILITY1

OPS Type Compatible: No

SOFTWARE COMPATIBILITY3

Content Management Software: SuperSign CMS
Control and Monitoring Software: SuperSign Control / Control+
Signage365Care: Yes

ACCESSORY2

Basic: Remote Controller, Power Cord, QSG, Regulation Book, Phone to RS232C Gender
Optional: Stand(ST-653T), Media Player, Wall Bracket(LSW350B), VESA Adapter(AM-B330S)

Downloads

6 files from the manufacturer

PDF Manuals & guides 43495565UM3DG_Arabic.pdf 2.6 MB PDF Manuals & guides 43495565UM3DG_ENG.pdf 2.5 MB PDF Manuals & guides MFL71694101_02_IG_200317.pdf 5.4 MB PDF Manuals & guides webOS4.1_ENG.pdf 6.8 MB URL Manuals & guides · Opens on manufacturer site User Guide URL Software & firmware · Opens on manufacturer site Software & Drivers (support page)

Questions about 55UM3DG

Is the LG 55UM3DG still sold new?

No. The manufacturer has discontinued the LG 55UM3DG and its 55UM3DG-B variant. If you already own one, or need a display with the same 55-inch UHD format, SmartRooms Qatar can quote a current equivalent or a compatible replacement. Send the model number and mounting details with your request so the quotation matches your installation.

Is this 55-inch display suited to a hotel lobby in West Bay?

Yes, if the lobby is indoors and air-conditioned. The 55UM3DG combines a 3,840 x 2,160 IPS panel, 350 nits typical brightness and a 39.9 mm body depth with a 9.9 mm top and side bezel. That suits a wall of welcome messages or wayfinding content visible from the front desk. A site survey will confirm the height for comfortable viewing.

Could it work in school corridors in Al Wakrah that run long hours?

The manufacturer rates the panel for 18 hours a day across seven days, and its typical panel life is 50,000 hours. That suits corridor timetables, announcements and wayfinding in a private school in Al Wakrah. Check the daily schedule with your facilities team, and keep the display within its 0°C to 40°C operating range, which means indoor use.

What brightness and viewing angle does the 55UM3DG offer?

It has a typical brightness of 350 cd/m², a 1,100:1 contrast ratio and a viewing angle of 178 x 178 degrees on its IPS panel. The surface has a 3% haze treatment and an 8 ms response time (G to G). For a reception area with strong daylight, test the position on site during the survey, because 350 nits may struggle near a window.

Can it be mounted in portrait orientation for a clinic reception in Al Sadd?

Yes. The panel supports both portrait and landscape use, which suits a tall directory or queue display in a clinic reception in Al Sadd. The VESA pattern is 300 x 300 mm, and the head weighs 19.0 kg, or 19.6 kg with the stand. Confirm the wall structure and whether you need the optional LSW350B wall bracket before installation day.

How does it cope with Qatar's summer heat?

The operating temperature is 0°C to 40°C with 10% to 80% humidity, so it is not rated for the 45°C-plus temperatures of a Doha summer in an uncooled space. Install it in an air-conditioned lobby or mall atrium, and ask SmartRooms Qatar to confirm the room temperature during the free site survey before you choose a location.

What inputs and control ports does it have?

It has three HDMI inputs with HDCP 2.2, one USB 2.0 Type A port, and RS232C in and out on a 4-pin phone-jack connector. The RS232C ports let a control system manage the screen and pass commands along. Audio output is set to Off, Fixed or Variable, and the built-in speaker means small rooms may not need external speakers.

Does it need an external media player?

No. The 55UM3DG has a Quad Core SoC and LG webOS, so it can run signage content without a separate media player. It is not OPS-compatible, so an OPS slot player cannot be fitted. A media player is listed as an optional accessory if your content workflow needs one, and SuperSign CMS manages content across screens.

Can it connect to Cisco video conferencing or Crestron control?

The manufacturer states Cisco compatibility for video conferencing and Crestron Connected certification for AV control. That suits a meeting room in Lusail or Msheireb where teams link to colleagues abroad and manual input changes on incoming calls are unwanted. Confirm your exact Cisco or Crestron platform during the quotation so the setup matches your system.

What happens if the screen is tilted or has a problem?

The display supports up to 15 degrees of tilt within 30°C and 50% humidity, for installations above eye level. It can also send email notifications when a problem occurs, such as the unit being knocked out of position by an external impact. That helps a facilities team in a high-ceiling atrium respond quickly without walking to the screen.

Does it work on Qatar's 240 V mains supply?

Yes. The power supply is rated 100-240V~ at 50/60Hz with a built-in power unit, which covers Qatar's 240 V, 50 Hz supply. Typical consumption is 95 W and maximum is 140 W, with 70 W in smart energy saving mode. A power cord is included in the basic accessories, so confirm the plug type for your sockets with the quotation.

How do schools and government buyers order several of these displays?

SmartRooms Qatar supplies against purchase orders (LPOs) and government tenders, including Monaqasat, and accepts bank transfer, cheque or purchase order payment. Delivery covers all 8 municipalities of Qatar, and free site surveys are available before installation. A school or ministry ordering several units can request one quotation, usually provided within one working day.