RECD device as per CPCB normsFor anyone operating an existing diesel generator, understanding an is important before choosing an emission-control solution. An RECD is not simply an additional exhaust component. It is a retrofit emission-control technology evaluated under a defined CPCB testing framework for applicable diesel genset applications.

CPCB has published a “System and Procedure for Emission Compliance Testing of Retro-fit Emission Control Devices (RECD) for Diesel Power Generating Set Engines Up to Gross Mechanical Power 800 kW,” revised on July 24, 2023. For generator owners, however, compliance is not just about purchasing equipment. Understanding the generator, selecting an appropriate product, installing it correctly, maintaining the system and keeping relevant documentation are all important parts of responsible operation.

What Every DG Set Owner Should Understand About RECD

Retrofit Emission Control DeviceRECD stands for .

The term “retrofit” refers to an emission-control solution intended for an existing, in-use diesel genset application.

This can be useful for organizations that already operate diesel generators and need to evaluate appropriate emission-control measures without automatically replacing the entire generating system.

However, an RECD should not be considered a universal product.

Its applicability can depend on the engine's technical characteristics, power range, phase and the documentation associated with the particular RECD model.

That is why the generator should always be identified before selecting the device.

Know Your Generator Before Ordering

A generator owner should maintain accurate technical information about every DG set.

Important details include:

Engine manufacturer
Engine model
Engine serial number
Gross mechanical power
Generator rating
Rated engine speed
Engine phase
Existing exhaust configuration
Installation location

The engine nameplate and manufacturer documentation are useful sources for this information.

Having these details ready makes technical discussions with an RECD supplier much easier.

It also reduces the possibility of selecting equipment based only on an approximate generator rating.

Why Gross Mechanical Power Matters

gross mechanical powerGenerator sets are commonly identified using kVA, but the CPCB RECD procedure refers to diesel genset engines according to .

The published procedure covers applicable diesel power-generating-set engines up to 800 kW gross mechanical power.

This distinction matters.

For example, if a facility says that it operates a “500 kVA DG set,” the supplier may still need the actual engine model and mechanical power before determining the appropriate RECD application.

Therefore, do not select an RECD solely from the kVA number printed on the generator.

Phase Applicability Also Matters

Another point that generator owners should understand is engine phase.

CPCB's published list of RECD manufacturers identifies products according to their applicability for Phase I, Phase II or both, along with their applicable engine power ranges and certification agencies.

This means that two RECD products may not have identical application coverage.

When requesting a quotation, ask the supplier to clearly state:

Which phase is covered by the proposed RECD?

The answer should correspond to the specific engine application.

Don't Assume Every RECD Fits Every DG Set

One of the easiest mistakes is to assume that an RECD is a universal device.

In reality, product applicability can vary.

A proper technical evaluation may consider:

Engine manufacturer
Engine model
Gross mechanical power
Engine phase
Exhaust arrangement
Product configuration
Certification/test documentation

CPCB's published manufacturer information itself shows different RECD products associated with different capacity ranges and phases.

Therefore, the exact product should be verified before purchase.

What Does CPCB Certification Information Tell You?

For a generator owner, certification or testing information provides an important reference when evaluating a product.

CPCB's RECD procedure establishes a structured system for emission-compliance testing.

CPCB's published list also identifies certification agencies associated with certified RECD manufacturers, including organizations such as ICAT and ARAI for listed products.

When purchasing, ask the supplier for product-specific supporting documentation rather than accepting a general statement such as “CPCB approved.”

The exact model and its documented application should be clear.

What Should a Generator Owner Ask the Supplier?

Before ordering an RECD, ask practical questions such as:

What is the exact RECD model?
Which engine models does it cover?
What gross mechanical power range is applicable?
Which engine phase is covered?
What test or certification documentation is available?
Which certification agency is identified?
What exhaust modifications are required?
What components are included?
What maintenance is required?
What warranty and service support are provided?

Written answers are preferable because they create a useful technical record for future reference.

Installation Is an Important Part of the Solution

Purchasing the correct device is only one part of an RECD project.

The existing DG exhaust system needs to be assessed before installation.

Consider:

Exhaust Pipe

Check the existing pipe diameter, connection type and routing.

Available Space

The RECD must fit safely within the available installation area.

Mounting

The device may require appropriate structural support.

Maintenance Access

Technicians should be able to inspect and service the equipment.

Electrical Requirements

If the system includes controllers or sensors, the necessary electrical arrangements should be identified.

Exhaust Back Pressure

The effect of the retrofit on exhaust back pressure should also be considered. CPCB's RECD procedure includes exhaust back pressure among the technical parameters considered during testing.

Installation should therefore be treated as an engineering activity rather than simply attaching a component to an exhaust pipe.

Why Generator Condition Matters

An emission-control retrofit does not eliminate the need for good generator maintenance.

Before installation, the condition of the DG set should be considered.

Areas worth reviewing include:

Engine servicing
Fuel system
Air intake
Lubrication
Exhaust system
Cooling system
Operating load
Existing smoke or abnormal operating conditions

If the engine has an underlying mechanical problem, that issue should be investigated separately.

Keeping the generator in good operating condition supports reliable performance of the complete system.

Maintenance Should Not Be Overlooked

Once installed, the RECD becomes part of the generator's operating environment.

The owner should understand the manufacturer's maintenance instructions and recommended inspection procedures.

Depending on the selected system, maintenance can involve:

Visual inspection
Exhaust-system inspection
Sensor checks
Controller checks
Cleaning
Component inspection
Replacement of specified parts

The exact requirements depend on the RECD technology and manufacturer.

Keep service records whenever maintenance is performed.

These records can help demonstrate that the equipment has been maintained according to the manufacturer's recommendations.

Keep Technical Documents Safely

Generator owners should maintain a dedicated file for the DG set and its RECD.

Useful documents include:

DG set details
Engine documentation
RECD datasheet
Exact model information
Certification/test documents
Installation report
Commissioning report
Warranty documents
Service records
Maintenance instructions
Relevant regulatory correspondence

Good documentation makes future servicing, troubleshooting and verification easier.

Don't Confuse an RECD With Any Pollution-Control Product

The market contains different types of exhaust and pollution-control equipment.

A generic exhaust accessory should not automatically be treated as an RECD under the CPCB framework.

An owner should ask:

Is this exact product being offered as an RECD, and what documentation supports that claim?

This distinction is particularly important when compliance is part of the purchasing objective.

Product identity and supporting documentation should always be checked.

Understanding the Role of a DG Generator Emission Control Device

DG generator emission control deviceA is a broad description of equipment designed to control emissions associated with diesel-generator operation.

An RECD represents a specific retrofit emission-control approach for applicable in-use diesel genset applications.

The two terms should therefore not automatically be treated as interchangeable.

If a supplier uses a broad phrase such as “emission control device,” ask for the exact product category, technical specifications and supporting documentation.

This provides much greater clarity during procurement.

Does Installing an RECD Automatically Mean the DG Set Is Compliant?

Generator owners should avoid assuming that installation alone provides a universal compliance guarantee.

Compliance-related evaluation can depend on:

Exact product
Engine application
Certification/test basis
Correct installation
Operating conditions
Maintenance
Current regulatory requirements
Site-specific conditions

CPCB's published information should be checked for the latest applicable requirements. Its website continues to publish current announcements and regulatory material.

Where applicable, requirements or conditions from the relevant State Pollution Control Board or Pollution Control Committee should also be considered.

Be Careful With Outdated Information

Environmental requirements can change.

An old supplier brochure, blog post or quotation may not reflect the latest official information.

For this reason, generator owners should verify important compliance-related decisions using current official sources.

CPCB's website is an important reference point for technical procedures, announcements and generator-related regulatory information.

This is especially important when a project has been planned using information obtained several years earlier.

How to Recognize a Responsible RECD Supplier

A reliable supplier should be able to discuss the application in technical terms.

Look for a supplier that:

Requests engine details
Checks the power range
Confirms phase applicability
Provides product documentation
Explains installation requirements
Discusses maintenance
Provides warranty information
Offers technical support
Clearly identifies the product model

Be cautious when a supplier recommends a product without asking for any information about the generator.

A proper retrofit solution should be selected according to the actual application.

Questions Every Generator Owner Should Ask About Price

Price is important, but it should not be the only consideration.

Ask whether the quotation includes:

RECD equipment
Controller
Sensors
Exhaust fabrication
Mounting supports
Installation
Electrical work
Commissioning
Transportation
Warranty
After-sales service

Two quotations with different prices may actually have very different scopes.

Always compare the complete package.

What If the DG Set Is Used Only Occasionally?

Occasional use does not mean that technical and maintenance considerations can simply be ignored.

Backup generators may remain unused for extended periods and then be expected to operate immediately during a power interruption.

The owner should therefore maintain the DG set and its emission-control equipment according to the relevant manufacturer's instructions.

Periodic inspection can help identify problems before an emergency operating situation occurs.

How Operators Can Help

The people who operate the DG set should understand the basic requirements of the installed system.

They should know:

Where the RECD is installed
What controller or indicators are present
What warning conditions mean
Who should be contacted for technical support
What routine checks are required

Operators should not modify or bypass emission-control equipment without appropriate technical authorization.

Any abnormal condition should be investigated according to the manufacturer's procedures.

When Should You Contact a Technical Team?

A technical evaluation is particularly useful when:

The generator has an unusual exhaust configuration.
Multiple DG sets are installed at one facility.
The DG room has limited space.
The exhaust system requires modification.
The generator's engine details are unclear.
The facility operates generators continuously or frequently.
The project involves multiple capacity ranges.
Compliance documentation needs to be reviewed.

Providing accurate information at the beginning can make the technical evaluation much more efficient.

How Aceget Can Help With RECD Requirements

For businesses evaluating retrofit emission-control solutions, Aceget can be approached with the relevant DG-set information so that the application can be assessed before the equipment is finalized.

Providing the engine model, power details, photographs of the DG set and exhaust arrangement can help establish the technical requirements for the project.

The final product selection should always be based on the particular generator, applicable documentation and the requirements relevant to the installation.

For current product information, specifications and support, buyers should refer to Aceget's official website and communicate their DG-set requirements directly with the company.

Final Takeaway

DG generator emission control deviceFor a generator owner, an RECD should be viewed as part of a complete emission-control project rather than as a standalone exhaust accessory. The process begins with understanding the DG set. Engine model, gross mechanical power, phase and exhaust configuration are important starting points. The exact RECD model should then be checked against its documented application and relevant certification/test information. For anyone evaluating a , the safest approach is to look beyond marketing claims. Confirm the exact product, review its documentation, assess the installation, understand maintenance requirements and retain all relevant records.

RECD Device as per CPCB Norms: What Every Generator Owner Must Know

A Quick Rundown of What's Required, Why It Matters & How to Stay Compliant