NFPA 110 · load bank testing
NFPA 110 load bank testing, explained plainly
Weekly, monthly, annual and 36 month requirements in one table, and a documented load bank test your inspector will accept. All brands, up to 1 MW.
The intervals
What NFPA 110 asks for, in plain English
Any emergency power supply system (EPSS) under NFPA 110 has a testing schedule the owner must keep, and a paper trail the authority having jurisdiction can ask to see.
| Interval | What the standard calls for | How JRC handles it |
|---|---|---|
| Weekly | Visual inspection of the emergency power supply system (EPSS) | We train your staff and supply a weekly log sheet with our number on it. |
| Monthly | Run at least 30 minutes at ≥30% of nameplate kW, or at the manufacturer's minimum exhaust temperature. Exercise the transfer switch. | Witnessed monthly tests on Total Care; remote monitoring on other tiers. |
| Annual | If monthly runs never reach 30% load or exhaust temperature, a supplemental load bank test: 30 min at ≥50%, then 60 min at ≥75%. | Included in Compliance and Total Care. Most small commercial units need it. |
| Every 36 months | Four hour run at ≥30% of nameplate or required exhaust temperature (Level 1 systems). | Scheduled and budgeted three years out. |
| Ongoing | Fuel quality: water, sediment and microbial growth in tanks, lines, pumps and filters. Annual diesel fuel quality testing. | Annual fuel sampling; polishing when results call for it. |
Summary of published NFPA 110 guidance. The enforceable version is the edition your authority having jurisdiction (AHJ) has adopted, plus local amendments. We confirm yours before we quote.
Why the annual test matters
Monthly exercise rarely reaches 30% load
A 150 kW unit backing up a typical building often carries well under 45 kW during its monthly exercise. That means the annual load bank test isn't an upsell. It's an obligation the owner already has.
Running diesel engines lightly also causes wet stacking: unburned fuel and carbon collecting in the exhaust. A load bank test burns it off and proves the unit can carry its rating before you need it to.
- Step 1
- 30 min @ ≥ 50%
- Step 2
- 60 min @ ≥ 75%
- Total
- 90 minutes
- 36 month
- 4 hr @ ≥ 30%
- Record
- Readings every 15 min
What you get
A test you can hand to a surveyor
- Resistive load bank connected by our technicians, no building load interruption
- Voltage, frequency, amperage, coolant and oil temperature and pressure logged through the test
- Pass/fail against the standard, signed and dated
- Deficiencies listed with photos and a priority
- Report delivered as a PDF for your EPSS binder
Free weekly inspection log
NFPA 110 calls for weekly visual inspection. Our one page log covers engine, battery, controls and room checks with space for 13 weeks of initials.
View the checklist Printable PDFStraight answers
Common questions
Can't find your question? Call 847-951-3678 and talk to a technician.
How often does NFPA 110 require load bank testing?
When monthly exercise doesn't reach 30% of nameplate kW or the manufacturer's minimum exhaust temperature, NFPA 110 calls for an annual supplemental load bank test: 30 minutes at 50% load followed by 60 minutes at 75%. Level 1 systems also need a four hour test at least every 36 months.
What is the NFPA 110 monthly generator test?
At least 30 minutes of running under load at 30% or more of the nameplate kW rating, or at the manufacturer's recommended minimum exhaust gas temperature, plus exercising the automatic transfer switch.
How long does a load bank test take?
The annual test runs 90 minutes under load. With hookup and teardown, plan on about three hours on site. The 36 month test runs four hours under load.
Will a load bank test interrupt building power?
No. A resistive load bank tests the generator by itself, so building loads stay on utility power throughout.
Which NFPA 110 edition applies to my facility?
Whichever edition your authority having jurisdiction has adopted, plus local amendments. Healthcare facilities may also fall under NFPA 99 and CMS requirements. We confirm yours before we quote.