A large price gap often reflects different ratings, models, system scope, manufacturing evidence, tests and service—not simply margin. The first professional step is to make every offer answer the same requirement.
Create one technical baseline and separate included, optional, by others and pending items. Price becomes comparable only after rating, equipment identity, system scope, quality, testing, delivery and support are aligned.
1. Build one request-for-quotation baseline
State location, target rating, prime/standby, frequency, voltage, critical loads, starting method, hours, environment, package, sound, runtime and delivery date.
Use one compliance sheet with standard, included, extra-cost, excluded and by-others responses. Otherwise a low price may omit ATS, cables, tanks, commissioning or records.
2. Ratings and equipment identities must reach model level
- Prime/standby kW and kVA, power factor and derating.
- Engine brand, full model, rating and serial traceability.
- Alternator model, excitation, AVR, temperature rise and protection.
- Controller, breaker, starting batteries and charger.
“Premium engine” or “equivalent alternator” is not a purchasable identity.
3. Align the systems outside the engine-generator core
Check base, mounts, radiator, silencer and flex, fuel, enclosure, lighting, stop, ATS, paralleling, distribution, monitoring, cables, grounding, spares and tools.
Separate factory supply, field installation, commissioning support and work by others. A cheap set with extensive unpriced site work can produce a higher project cost.
4. Compare visible and traceable quality evidence
Request structural steel, weld and coating, locks and seals, cable and terminal workmanship, breakers, protection, nameplates and serial evidence. “High-quality materials” is not a specification.
Agree the photos, drawings, component schedules and manufacturing hold points that correspond to the quotation and final unit.
5. Testing and records determine whether the set can be accepted
Define start/stop, no-load, voltage/frequency, staged load, alarms, emergency stop, ATS or paralleling tests, including load, duration, records and witnessing.
Require datasheets, diagrams, manuals, test reports, packing list, spares and warranty. “Factory tested” without scope and results leaves no acceptance boundary.
6. Compare schedule, warranty and local execution
Review manufacturing, freight, packaging, tax, payment, validity, acceptance, warranty start, coverage and exclusions. Define service city, response process, remote/field method, labour/travel and parts lead time.
Global warranty or local team claims matter only when execution terms are written.
7. Close the comparison with four response classes
Classify each line as compliant, conditionally compliant, extra cost or non-compliant. Price extras, expose assumptions and decide whether non-compliance is disqualifying. Compare technical risk, delivery risk, operating cost and total price separately.
The recommendation should explain load capability, site fit, quality evidence, support responsibility and the all-in scope.