RECD compliance for diesel generatorsManaging becomes more complex when a company operates several DG sets across one facility, multiple plants, construction sites, commercial buildings or industrial locations. In such cases, purchasing an RECD for one generator is very different from planning a structured bulk procurement program. A bulk project needs more than a quantity-based quotation. Every DG set should be identified correctly, the proposed RECD should be matched with its applicable engine and power range, and documentation, installation, warranty and after-sales support should be planned from the beginning.

CPCB has published a system and procedure for emission-compliance testing of Retrofit Emission Control Devices (RECDs) for diesel power-generating-set engines up to 800 kW gross mechanical power. The procedure was revised on July 24, 2023. CPCB's published list of certified RECD manufacturers also shows that applicability varies by in-use diesel genset engine power range and Phase I/Phase II classification. The list available from CPCB is dated May 9, 2025. For organizations planning multiple installations, this makes technical verification and project documentation especially important.

Why Bulk RECD Procurement Needs a Different Approach

Buying one RECD usually involves one generator, one site and one installation.

A bulk order may involve:

Different DG-set capacities
Different engine manufacturers
Different engine models
Different engine-power ranges
Different installation locations
Different exhaust arrangements
Different phases
Different service requirements

Therefore, it is risky to assume that one RECD model can automatically be supplied for every generator in a large fleet.

DG-set inventoryA bulk procurement strategy should begin with a , not with a quantity such as “20 RECD units.”

Don't Group DG Sets Only by kVA

A common procurement shortcut is:

“We have ten 500 kVA DG sets, so we need ten identical RECDs.”

That may be appropriate only after the technical specifications have been verified.

CPCB's RECD documentation emphasizes testing combinations using the engine's gross mechanical power in kW. An earlier CPCB vendor reference also notes that corresponding kVA ratings should be checked against the data plates of the engines and DG sets.

Therefore, bulk buyers should collect both:

DG-set capacity in kVA

and

engine gross mechanical power in kW

before final product selection.

Create Product Groups Before Ordering

After collecting the DG-set information, divide the fleet into technical groups.

For example:

Group A

Similar engine model and applicable power range.

Group B

Different engine model but similar power range.

Group C

Different phase or application requirements.

Group D

Generators requiring different physical installation arrangements.

This allows the supplier to determine whether one RECD model can be used across a group or whether multiple products are required.

technical standardization where appropriateThe objective should be , not forced standardization where it is unsuitable.

Bulk Quantity Does Not Replace Product Verification

A supplier may offer an attractive price for 25 or 50 units.

Before accepting the quotation, verify:

Exact RECD model
Manufacturer
Applicable engine-power range
Phase
Certification information
Installation scope
Warranty
Service coverage

CPCB's published list identifies manufacturers and applicable engine-power ranges along with certification-agency information.

A bulk discount is valuable only when the products being purchased are appropriate for the intended DG sets.

What Should a Bulk Quotation Contain?

A detailed quotation should ideally separate technical and commercial information.

Product Information

Manufacturer
RECD model
Quantity
Applicable engine range
Phase
Technical specifications

Installation

Site survey
Equipment installation
Exhaust modification
Mounting
Electrical work, where applicable
Commissioning

Commercial

Unit price
Installation price
Transportation
Taxes
Additional fabrication
Warranty
Payment terms

Support

Service coverage
Preventive maintenance
Spare parts
Technical support

This makes supplier comparison much easier.

Avoid One-Line Bulk Quotations

A quotation such as:

“RECD system – 20 Nos. – ₹_____”

does not provide enough information for a technical procurement decision.

Ask for a detailed schedule identifying the product and scope.

For large projects, the purchase order should ideally identify each DG set and the corresponding RECD model.

Warranty: What Should Buyers Check?

Warranty is particularly important when buying multiple units.

Do not look only at the duration.

Check what the warranty actually covers.

Important questions include:

What is the warranty period?
When does it begin?
Which components are covered?
Is installation workmanship covered?
Are sensors covered?
Is the controller covered?
Are replacement parts covered?
Is labour covered?
Is travel covered?
What exclusions apply?

A written warranty document is preferable to a verbal assurance.

Bulk Warranty Should Be Clearly Defined

Suppose a company purchases 30 RECD systems.

If one unit develops a problem, the buyer should know:

Whom to contact
How the complaint is registered
What information must be provided
Who performs the inspection
How replacement is handled
Whether the supplier sends a technician
What happens if a component is unavailable

These details become more important as the number of installed systems increases.

Service-Level Expectations for Large Fleets

Bulk customers should discuss service arrangements before installation.

A service plan may define:

Initial Response

How quickly will the supplier acknowledge a complaint?

Technical Diagnosis

Who will identify the problem?

Site Visit

When is an on-site inspection required?

Replacement

How are defective components handled?

Escalation

Who handles unresolved technical issues?

The exact response commitments should be agreed contractually where appropriate.

Local Service and Central Technical Support

A strong support arrangement can combine two levels of assistance.

Field Support

Useful for:

Installation
Inspection
Physical troubleshooting
Maintenance

Central Engineering Support

Useful for:

Product-specific technical questions
Certification documentation
Controller-related issues
Complex troubleshooting
Engineering clarification

For a large fleet, knowing how these two support levels work together can prevent unnecessary delays.

Conduct Site Surveys Before Mass Installation

If the sites have different exhaust configurations, a pre-installation survey can reduce unexpected fabrication work.

Record:

Exhaust diameter
Flange dimensions
Pipe routing
Number of bends
Silencer position
Mounting area
Electrical connection
Service access

A single bulk quotation should not assume that every installation site is physically identical.

Exhaust Back Pressure in Bulk Projects

The exhaust arrangement deserves special attention when multiple DG sets are being retrofitted.

CPCB's RECD procedure includes exhaust back pressure among the technical parameters considered during compliance testing.

Therefore, each installation should be evaluated according to the actual exhaust arrangement.

Do not assume that the same fabrication drawing can be applied blindly to every DG set.

Where generators differ significantly, installation drawings may need to be site-specific.

Documentation Management for Bulk Orders

Large projects can generate substantial documentation.

Create a folder for each DG set.

Folder 01 — DG-01

Engine details
Nameplate photographs
RECD model
Technical datasheet
Certification/test documentation
Purchase order
Installation report
Commissioning report
Warranty
Maintenance records

Repeat the same structure for each generator.

This creates a traceable history for every installed unit.

Use Serial Numbers

Record the RECD serial number against the DG-set identification number.

For example:

DG-01 → RECD Serial No. ______

DG-02 → RECD Serial No. ______

This makes future warranty and service claims much easier.

Bulk Procurement and Certification Records

When purchasing multiple units, ask the supplier how the product documentation relates to the ordered quantity.

Verify:

Exact model
Product type
Applicable engine range
Phase
Certification/test reference
Manufacturer

CPCB's published manufacturer list identifies certified RECD manufacturers and provides applicability ranges for listed products.

However, buyers should still request and retain product-specific documentation from the supplier.

Do not assume that a company appearing on a list means every product it sells has identical applicability.

Ask About Installation Training

For a large DG fleet, the customer's maintenance team can benefit from basic product orientation.

Ask the supplier to explain:

System components
Controller indications
Alarm handling
Inspection requirements
Maintenance intervals
Safe operating practices
Escalation process

The operator should understand when to contact the supplier instead of attempting an unauthorized modification.

Spare Parts Planning for Large Installations

A company with several RECD installations may benefit from planned spare-parts management.

Ask the supplier:

Which components are service items?
Which parts are commonly replaced?
What is the expected availability?
Can critical parts be stocked locally?
What is the ordering process?

The exact parts depend on the selected RECD.

The objective is to avoid a situation where one minor component keeps an essential DG set's emission-control system out of service for an extended period.

Evaluating an RECD Manufacturer in India for Bulk Supply

RECD manufacturer in IndiaWhen selecting an for a multi-unit project, examine the supplier's ability to support the entire project lifecycle.

Consider:

Manufacturing Capability

Can the supplier meet the required quantity without compromising product consistency?

Technical Capability

Can the supplier evaluate different DG-set configurations?

Documentation

Can the supplier provide appropriate product-specific documents?

Installation

Can the supplier manage installations across the required locations?

Service

Can the supplier provide post-installation support?

Warranty

Are warranty terms clearly documented?

Spare Parts

Can service components be supplied when required?

CPCB's published RECD manufacturer list provides an official reference for listed manufacturers and their documented applicability ranges.

For procurement, this should be supplemented with current product documentation and a clear commercial and technical scope.

Questions to Ask Before Signing a Bulk Purchase Order

Use these questions during the final supplier meeting.

Product

What exact RECD model will be supplied?
Which DG sets will receive that model?
What engine-power range applies?
What phase applies?

Documentation

What certification/test documents will be supplied?
Will the model number on the documents match the supplied equipment?
Will complete installation and maintenance manuals be provided?

Installation

Who performs installation?
Is site survey included?
Is exhaust fabrication included?
Is commissioning included?

Warranty

What is the warranty period?
Which components are covered?
What is the warranty-claim process?

Service

Where is the nearest service team?
How are technical complaints handled?
Are spare parts readily available?

Delivery

What is the delivery schedule?
Will delivery be phased by site?
How will serial numbers be recorded?

These questions can prevent many avoidable disagreements after the purchase order is issued.

Don't Make Quantity the Main Selection Criterion

A supplier offering a large discount may appear attractive.

But the better question is:

Can the supplier deliver the correct product, documentation, installation and support for every DG set in the fleet?

For a single DG set, an incorrect selection can affect one installation.

For 20 or 50 DG sets, the same mistake can multiply across the entire project.

Bulk procurement therefore requires stronger technical controls, not fewer.

Final Takeaway

fleet-management and technical-support projectRECD manufacturer in IndiaBulk RECD procurement should be treated as a , not simply a large equipment purchase. Begin with a complete inventory of the DG sets. Record engine model, gross mechanical power, DG rating, phase and location. Then match each generator with an appropriate RECD product and retain the supporting documentation. For organizations evaluating an , bulk purchasing should therefore include much more than a discounted unit price. Product applicability, documentation, installation capability, commissioning, warranty, spare-parts availability and after-sales service all deserve attention. Before finalizing a bulk project, verify the latest CPCB information and any applicable State Pollution Control Board/Pollution Control Committee requirements. Regulatory requirements and official information can change, so current official sources should take priority over older articles, advertisements or informal compliance claims.

RECD Compliance for Diesel Generators: Bulk Orders, Warranty & Support Explained

Everything You Need to Know Before Placing a Bulk Order — Warranty, Support & Delivery