A generator inspection form is the record that a standby generator was looked at, run and left ready — so that when the power fails it starts, takes the load and keeps it. This one covers the weekly look-over, the monthly run under load and the deeper annual service in one form, with the readings that show a set is healthy written down rather than ticked. Fill it in here and download the report as a PDF, or use it on your phone beside the set: speak while you walk, and the document writes itself.
Why standby generators fail on the day
A standby set spends almost its whole life sitting still, which is exactly what it is worst at. Starting batteries run down or age out, diesel picks up water and grows sludge, coolant heaters fail and the engine sits cold, and a set that is only ever started for five minutes off load slowly coats its exhaust with unburned fuel.
Most of those failures give warning to anyone who looks. That is what a routine inspection is: someone checking the things that quietly fail, writing down what they found, and making sure the set is back in AUTO before they leave.
Weekly, monthly, annual
Choose the type of visit at the top and the form adjusts. A weekly check is a look-over without necessarily running the set: fuel, fluids, leaks, battery and charger, and the controller showing no alarms. A monthly visit adds a run under load and, where there is one, a transfer-switch test. A quarterly or annual service adds the deeper items — proving the shutdown safeties, the alternator, connections and mounts — that the maker's schedule calls for.
For emergency power systems in the US, NFPA 110 sets the maintenance and testing regime and many authorities adopt it, often through the fire or health code. It asks for weekly inspection and a monthly exercise under load. Check the edition your authority has adopted and the maker's manual, and use this form to record what you did.
Run it under real load
A diesel engine run lightly never gets hot enough to burn all its fuel. The unburned fuel and soot collect in the exhaust as a black, oily residue — wet stacking — and over time it costs power and reliability. Running on building load through the transfer switch, or on a load bank, is the cure.
NFPA 110 asks for monthly runs of at least 30 minutes at no less than 30 percent of the nameplate rating, or at a load that brings the exhaust up to the maker's recommended temperature, with a load-bank test when that cannot be met. Record the load you actually carried so the pattern is visible over a year.
Readings worth writing down
A tick that says "run test OK" tells the next technician nothing. The numbers do. Battery voltage at rest, start time, load in kilowatts or as a share of the rating, volts and amps on each phase, frequency, oil pressure and coolant temperature, and the run-hours meter before and after. Compared month to month, they show a weakening battery or a cooling problem well before a failed start.
Common questions
How often should a standby generator be inspected?
Commonly a weekly visual inspection, a monthly run under load, and a full service once or twice a year to the maker's schedule. Emergency systems that serve life-safety loads often have these intervals set by the code your authority has adopted, such as NFPA 110 in the US.
How long should a generator run during a monthly test?
Under NFPA 110, at least 30 minutes under load — typically no less than 30 percent of the nameplate rating, or enough to reach the maker's recommended exhaust temperature. A short run with no load does little except use fuel and contribute to wet stacking.
What is wet stacking?
Unburned fuel and soot collecting in the exhaust of a diesel engine that is run too lightly. You see it as black, oily residue at exhaust joints or the outlet. Regular runs under real load, and a load bank when the building load is too low, prevent it.
Do I need a load bank?
Only when the building cannot give the set enough load during its monthly runs. Many sites hire one for the annual test anyway, because it lets the set run at a higher, steady load without disturbing the building.
Does this form work for natural gas and propane generators?
Yes. Pick the fuel in the details and the diesel-only checks — water in the fuel, fuel quality, the day tank — are hidden and kept out of the score, while a gas supply check appears instead.
Does this replace the maker's service schedule?
No. The maker's manual decides service intervals, oil and coolant specifications and test procedures. This form records that the inspection and service were done and what was found.