The 2GX13 T5 Circline 55W 840 Cool White Circular Fluorescent Tube is a high-output circular replacement lamp designed for compatible fittings requiring a 55W T5 fluorescent Circline lamp with a 2GX13 4-pin base.

Producing a clean 4000K Cool White (840) light, this 55W circular fluorescent tube provides strong, broad and even illumination from its compact ring-shaped design.

With an approximate 300mm outside diameter and slim 16mm T5 tube diameter, this lamp is commonly used in compatible commercial, residential and specialist circular light fittings where high light output and compact dimensions are required.

This lamp is particularly useful for replacing older or difficult-to-find 55W/840 2GX13 T5 Circline fluorescent lamps, including compatible OSRAM LUMILUX, Sylvania T5 Circline Plus and other equivalent lamps.

Key Features

• 55W circular fluorescent lamp
• T5 Circline design
• 2GX13 4-pin base
• 840 colour code
• 4000K Cool White
• High-output circular fluorescent lamp
• Approx. 300mm outside diameter
• Approx. 16mm tube diameter
• Circular / ring-shaped design
• Broad and uniform light distribution
• CRI approximately 80+
• Suitable for compatible electronic control gear
• Replacement for compatible 55W/840 2GX13 Circline lamps
• Suitable for commercial, residential and professional lighting applications

Technical Specifications

*Comparable OSRAM and Sylvania 55W/840 2GX13 Circline lamps are rated at approximately 4200–4250 lumens. Always refer to the supplied lamp markings where an exact lumen rating is required.

Compatible & Equivalent Lamp References

This 55W 840 2GX13 T5 Circline fluorescent lamp may be suitable as a replacement for equivalent lamps requiring:

55W • T5 • 2GX13 • 4-Pin • 840 • 4000K • Approx. 300mm

Common replacement and cross-reference numbers include:

OSRAM / LEDVANCE Cross-Reference

A particularly useful replacement reference is:

OSRAM LUMILUX FC 55W/840 – 2GX13

Other identification numbers associated with this lamp include:

FC55840

4050300528588

The OSRAM specification uses the important replacement characteristics:

55W • T5 • 2GX13 • 840 • 4000K

The OSRAM version is approximately 305mm in diameter, compared with approximately 300mm listed for this NZ Lights lamp, so the physical space available in the fitting should also be checked.

Sylvania Cross-Reference

Another useful replacement reference is:

Sylvania T5 Circline Plus 55W/840

Sylvania product reference:

0000528

EAN:

5410288005287

The Sylvania lamp is also a 55W, 840, 4000K, 2GX13 T5 circular fluorescent lamp, making this an excellent identification reference when replacing older Sylvania Circline lamps.

Important: Manufacturer references are provided as a replacement and identification guide. Always confirm wattage, base, pin arrangement, colour temperature and physical dimensions before ordering.

Common Applications

The 2GX13 T5 55W 840 Circline fluorescent lamp is commonly used in compatible:

• Commercial ceiling fittings
• Offices
• Retail stores
• Hotels and hospitality environments
• Restaurants
• Public buildings
• Residential ceiling fittings
• Apartment common areas
• Supermarkets
• Display lighting
• Work areas
• Specialist circular fluorescent fixtures

The high-output 55W circular design provides strong, uniform illumination while allowing the light source to fit within relatively shallow circular fixtures.

How to Identify the Correct Replacement

Before ordering, check the markings printed on your existing circular fluorescent tube.

For this product, look for:

55W + T5 + 2GX13 + 840 + 4000K

You may also find markings such as:

55W/840

FC 55W/840

FC55840

2GX13

840

4000K

or another manufacturer's model or catalogue number.

Also measure the outside diameter of your existing circular lamp.

For this NZ Lights product:

Outside Diameter: Approx. 300mm

Tube Diameter: Approx. 16mm

What Does 840 Mean?

The 840 colour code is an important identification number when replacing fluorescent lamps.

8 = CRI approximately 80+

40 = approximately 4000K colour temperature

Therefore:

840 = CRI 80+ / 4000K Cool White

This is particularly useful when identifying an older lamp because 840 may be printed on the tube even when “4000K” is not shown separately.

2GX13 4-Pin – Important Compatibility Information

This lamp uses a 2GX13 4-pin base.

The base configuration is extremely important when replacing a Circline fluorescent lamp.

For this product, check:

✓ 55W

✓ T5 Circline

✓ 2GX13

✓ 4-Pin

✓ 840

✓ 4000K Cool White

✓ Approx. 300mm outside diameter

Do not choose a circular fluorescent lamp based only on wattage or diameter. A similar-looking lamp with a different connector may not fit or operate correctly.

840 / 4000K Cool White Light

The 840 / 4000K Cool White colour provides a clean, neutral-white appearance particularly suited to functional and commercial lighting.

Common applications include:

• Offices
• Retail stores
• Commercial interiors
• Kitchens
• Work areas
• Public buildings
• Apartment common areas
• Hospitality environments
• Utility areas
• General-purpose ceiling lighting

Compared with 827/2700K Warm White, 840/4000K provides a cleaner and noticeably cooler-looking light.

If you're replacing one lamp within an existing installation, check for 840 or 4000K on your old tube to maintain a similar light appearance.

How to Measure a Circline Lamp

Measure straight across the complete circular lamp from the outside edge of the tube on one side to the outside edge on the opposite side.

For this product:

Outside Diameter: Approx. 300mm

Tube Diameter: Approx. 16mm

Also check the 2GX13 4-pin connector.

Two circular fluorescent lamps can have very similar diameters while using different bases or electrical configurations.

Need Help Finding the Correct Circline Lamp?

If you're unsure whether this 55W T5 2GX13 840 Circline lamp is the correct replacement, send NZ Lights a clear photo of your existing lamp showing the printed markings and connector/base.

If possible, also provide the outside diameter of the existing circular tube.

We can help identify the correct wattage, base, colour code, colour temperature and physical size required for your fitting.

Why Buy from NZ Lights?

NZ Lights specialises in replacement lamps and hard-to-find lighting products for residential, commercial and professional applications throughout New Zealand.

• Specialist replacement lighting range
• Hard-to-find Circline and fluorescent lamps
• 2GX13 circular fluorescent lamps available
• Multiple wattages and colour temperatures
• Single and bulk quantities available
• NZ-based support
• Fast nationwide delivery
• Daily dispatch from Christchurch, New Zealand