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Core calculation

For “Core calculation”, required usable AC energy (kWh) = Σ(load watts × backup hours) ÷ 1000.

Start here

For “Core calculation”, required usable AC energy (kWh) = Σ(load watts × backup hours) ÷ 1000. Then adjust for inverter losses and the battery’s permitted usable depth of discharge. Add margin for ageing and surge, but stay within the inverter and battery manufacturer’s supported design.

What applies to this exact problem

Required usable AC energy (kWh) = Σ(load watts × backup hours) ÷ 1000. Then adjust for inverter losses and the battery’s permitted usable depth of discharge. Add margin for ageing and surge, but stay within the inverter and battery manufacturer’s supported design.

LoadWattsHoursWh needed
LightsMeasured totalDesired backupW × h
FansMeasured totalDesired backupW × h
Router / electronicsMeasuredDesired backupW × h
Refrigerator or motor loadRunning + surgeDuty cycle estimateUse realistic cycling
Action flow

Check these first

  • Load: Watts.
  • Lights: Measured total.
  • Fans: Measured total.

Fix it in this order

  1. Load: Watts.
  2. Lights: Measured total.
  3. Fans: Measured total.
  4. Router / electronics: Measured.
  5. Refrigerator or motor load: Running + surge.

Evidence to keep

  • Signed quote and scope — keep it with the evidence for “Core calculation”.
  • Module/inverter serials and warranty — keep it with the evidence for “Core calculation”.
  • DISCOM/portal application IDs — keep it with the evidence for “Core calculation”.
  • Generation data, photos, and installer tickets — keep it with the evidence for “Core calculation”.

Do not make it harder

  • Paying the final amount before checking agreed milestones For “Core calculation”, that can hide whether the underlying issue is actually resolved.
  • Assuming low generation is automatically a bad panel For “Core calculation”, that can hide whether the underlying issue is actually resolved.
  • Treating installer completion as DISCOM/subsidy completion For “Core calculation”, that can hide whether the underlying issue is actually resolved.

How you know it is fixed

  • The official record and your real-world result agree for “Core calculation”.
  • You have enough written evidence to prove the issue is finished if it returns later for “Core calculation”.

If this still isn't resolved

  1. Installer/vendor grievance State the unresolved issue explicitly: “Core calculation”.
  2. DISCOM/portal grievance route State the unresolved issue explicitly: “Core calculation”.
  3. Consumer forum or other official remedy where appropriate State the unresolved issue explicitly: “Core calculation”.

Parent-guide references

These references support the parent guide and escalation context. Verify provider-, model-, policy-, or jurisdiction-specific details before an irreversible step.

Need the complete context?

This page solves one branch. The parent guide covers the full decision, edge cases, alternatives, and related checks.

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