Replacing an Old or Discontinued RCBO – What You Need to Know

Why Do RCBOs Become Discontinued?

Electrical manufacturers regularly develop new genFinding a replacement RCBO can become more difficult when the original device is no longer manufactured.

Consumer units can remain in service for many years, while manufacturers regularly update their ranges of circuit breakers, RCBOs and other protective devices.

As a result, you may need to replace a single RCBO only to discover that the exact model has been discontinued.

This guide explains how to identify an older RCBO, what to check before replacing it and why the newest device from the same manufacturer isn't necessarily a direct replacement.erations of consumer units and protective devices.

A product range may be replaced because of:

  • New product development
  • Changes in standards
  • Updated consumer unit designs
  • New protective device technology
  • Changes in manufacturing
  • Introduction of new product ranges

This doesn't necessarily mean that every consumer unit containing the older devices immediately needs replacing.

It does mean that sourcing individual replacement components can become more difficult over time.

Start With the Exact RCBO Model

If an existing RCBO needs replacing, start by identifying exactly what is currently installed.

Do not begin by searching only for something such as:

32A RCBO

There can be many completely different RCBOs with that rating.

Instead, look for:

  • Manufacturer
  • Product range
  • Manufacturer part number
  • Current rating
  • Trip curve
  • Residual current rating
  • RCD type
  • Breaking capacity
  • Number of poles

The Manufacturer Part Number (MPN) is particularly useful when searching for discontinued equipment.

Why Is the MPN Important?

The MPN identifies the specific product rather than simply describing its electrical rating.

For example:

Crabtree Loadstar 6FSR20/30C

is considerably more specific than:

Crabtree 20A RCBO

The full model number can help you locate technical information and establish exactly which generation of protective device you have.

When searching online for an older RCBO, using the MPN will often produce much more relevant results.

Identify the Consumer Unit as Well

Don't only identify the RCBO.

Try to establish which consumer unit it is installed in.

Look for:

  • Manufacturer
  • Product range
  • Consumer unit model
  • Product code
  • Labels on the enclosure
  • Existing protective device range

A photograph of the complete row of breakers can also be useful.

The consumer unit information can help determine which protective device range was originally intended for the assembly.

Can I Just Buy the New Version?

Not automatically.

A manufacturer may replace an old RCBO range with a newer generation, but that doesn't necessarily mean the newer product is a direct replacement for every older consumer unit.

Changes between generations can include:

  • Busbar design
  • Terminal positions
  • Device dimensions
  • Neutral arrangements
  • Connection systems
  • Breaking capacities
  • Electrical characteristics

The newer RCBO may look extremely similar while still being different in important ways.

Manufacturer compatibility information should therefore be checked before treating a newer product as a replacement.

Can I Use a Different Brand Instead?

Do not assume that an RCBO from another manufacturer can be used simply because it fits onto the DIN rail.

For example, a Wylex consumer unit should not automatically be fitted with a Hager, Crabtree or Eaton RCBO just because the device appears to fit.

Consumer units are assemblies designed around particular components.

Physical fit alone does not establish compatibility.

For more information, see our RCBO Compatibility Guide – Will an RCBO Fit My Consumer Unit?

What If I Find the Exact Original RCBO?

Finding the same original MPN can make product identification considerably easier.

You can compare the replacement device directly with the existing model and verify its specifications.

However, finding the same model number does not remove the need to check the condition of the replacement device and suitability for the installation.

This is particularly important when purchasing older electrical equipment.

New Old Stock vs Used RCBOs

Discontinued RCBOs can sometimes be available in several conditions.

Brand New

A product that has not previously been installed or used.

Older discontinued equipment can sometimes remain unused in storage long after manufacturing has stopped.

New Other

An unused product that may no longer have its original packaging or may have damaged or incomplete packaging.

Used

A device that has previously been installed.

The condition should always be clearly stated so that the buyer understands what they are purchasing.

At ReCircuit Resale, we separate these conditions within our product listings.

What Specifications Need to Match?

When identifying a replacement, there are several specifications to consider.

These can include:

Manufacturer and range

The device needs to be appropriate for the consumer unit.

Current rating

For example, 6A, 16A, 20A or 32A.

Trip characteristic

For example, B Curve or C Curve.

Residual current rating

Often 30mA in domestic applications.

RCD type

For example, Type A or Type AC.

Breaking capacity

For example, 6kA or 10kA depending on the product.

Pole and neutral configuration

This varies between RCBO designs.

Matching one of these characteristics does not mean the remaining specifications can be ignored.

Don't Change the Rating Just Because It's Available

When a particular discontinued RCBO becomes difficult to find, it may be tempting to use a different current rating or trip curve because that device is easier to source.

For example:

B32 → B40

or:

B32 → C32

These are not like-for-like substitutions.

The protective device characteristics are determined by the requirements of the circuit.

A different rating or characteristic should not be installed simply because the original product is unavailable.

What If the Exact RCBO Can't Be Found?

If the original device is unavailable, the next step should be to establish whether the manufacturer specifies a compatible replacement.

Technical documentation may identify:

  • Replacement ranges
  • Compatible newer devices
  • Approved combinations
  • Accessories or conversion requirements

If a suitable replacement cannot be established, the wider consumer unit installation may need to be assessed by a suitably competent person.

Do not improvise a replacement based solely on physical appearance.

Should I Replace the Whole Consumer Unit?

Not every discontinued RCBO automatically means that the entire consumer unit needs replacing.

If an appropriate compatible replacement can be sourced, maintaining the existing equipment may be possible.

However, there are situations where upgrading or replacing the consumer unit may be more appropriate.

This depends on factors including:

  • Condition of the existing equipment
  • Age and type of consumer unit
  • Availability of compatible parts
  • Requirements of the installation
  • Existing protection
  • Applicable regulations

This decision should be based on an assessment of the installation rather than simply the availability of one replacement breaker.

Buying Used Discontinued RCBOs

Used electrical protective devices require particular care because their previous history may not always be known.

Condition should be clearly stated and the device should be appropriately assessed before being placed back into service.

A used RCBO should never be assumed to be suitable simply because it looks clean or operates mechanically.

ReCircuit Resale clearly identifies products sold as Used rather than presenting them as new equipment.

Why Are Discontinued RCBOs Still Sought After?

There are many older consumer units still in service.

If an individual protective device requires replacement, sourcing the correct original model can sometimes avoid unnecessary changes to otherwise serviceable equipment, subject to the suitability and condition of the installation.

This creates continued demand for protective devices that manufacturers may no longer produce.

Older model numbers can therefore remain actively searched for years after production has ended.

How to Search for a Discontinued RCBO

The best search term is normally the exact manufacturer and MPN.

For example, instead of searching:

20A Crabtree RCBO

search:

Crabtree Loadstar 6FSR20/30C

If you don't know the MPN, identify as much information as possible from the existing device before searching.

For more information, see our How to Identify Your Existing RCBO guide.

Can't Find Your RCBO?

ReCircuit Resale specialises in acquiring a changing range of new, surplus and used electrical equipment.

This means we regularly stock older and discontinued RCBOs, RCDs and other consumer unit components that may no longer be widely available through conventional electrical wholesalers.

If you can't find the device you need, send us:

  • A clear photograph of the RCBO
  • Photograph of all visible markings
  • Manufacturer
  • MPN if readable
  • Current rating
  • Photograph of the surrounding breakers
  • Photograph of the consumer unit label

Even if the exact product isn't currently listed on our website, we may be able to identify it or advise whether we have relevant stock available.

Finding Discontinued Electrical Products at ReCircuit Resale

Our stock changes regularly depending on the surplus and used electrical equipment we acquire.

We commonly stock protective devices from manufacturers including:

  • Wylex
  • Hager
  • Crabtree
  • Eaton
  • Other established electrical manufacturers

Where possible, our listings include detailed identification information such as:

  • Manufacturer
  • Product range
  • MPN
  • Current rating
  • Trip curve
  • RCD type
  • Compatibility information
  • Condition

This makes it easier to search by the actual device you need rather than browsing through hundreds of similar-looking breakers.

Important: RCBOs are electrical safety devices. Finding an identical or similar model does not by itself confirm suitability for a particular installation. Compatibility and electrical characteristics should be verified against manufacturer information and applicable wiring regulations. Consumer unit work should be carried out by a suitably competent person.