What Preventive UPS Maintenance Checklist Should You Require from a Service Provider: Including Reports, Logs, Firmware, and Battery Capacity Testing?

Scope, terms and assumptions

This guide covers preventive maintenance of stationary UPS systems with valve-regulated (VRLA) or vented lead-acid batteries, from single-phase rack and tower units to three-phase systems in server rooms, data centres, hospitals, plants and public buildings. It is written for the person who buys and audits the service. It is not a procedure for the technician: the steps for any model are in its manual and in a written method of procedure. Lithium-ion battery systems follow their own manufacturer and battery management system rules and are outside the battery tables.

• Minor and major visit: a minor visit inspects and measures while the UPS carries the load normally. A major visit adds work that needs the load moved off the UPS or shut down.
• Cell, block, jar: a cell is one 2 V lead-acid element; a block or jar is a case holding one or more cells, often 12 V. A string is jars connected in series.
• Float voltage: the voltage the charger holds the battery at when it is fully charged. AC ripple: the small AC component the UPS imposes on the battery, which heats and ages it.
• Ohmic value: a cell’s internal impedance, resistance or conductance, measured with a dedicated tester. It is a trending tool, not a measure of capacity.
• Capacity test: a controlled discharge at a defined load to a defined end voltage, which measures how much of its rating the battery still delivers.
• MOP: method of procedure, the written, approved step list for work that moves or isolates the load. One-line: the single-line diagram of the electrical supply. EPO: emergency power off. EMP: the electrical maintenance program NFPA 70B asks the owner to keep.

Two rules apply throughout. The manufacturer’s maintenance instructions come first wherever they exist. And for equipment under warranty or an OEM service contract, the manufacturer’s terms decide who may open the unit, change firmware or replace batteries; firmware comes only from the manufacturer.

The checklist, interval by interval

Table 1 is the checklist to attach to a contract or to audit a provider’s reports against. It combines the NFPA 70B UPS intervals, the IEEE 1188 battery items, Vertiv’s battery measurements and the semi-annual and annual scopes that Mitsubishi Electric Power Products (MEPPI) publishes. Table 2 is a record sheet for each visit. Print this page or copy both tables into your own form.

Three notes make Table 1 work in practice. Quarterly battery readings: IEEE 1188 asks for per-jar readings every quarter. If your UPS gets only two visits a year, cover the other two quarters with a battery-only visit or a battery monitoring system that records per-jar values. Minor versus major visits: a minor visit does not move the load, except for a self-test on a small unit (below). A major visit puts the load on the maintenance bypass, which is raw utility power with no battery behind it, or needs a planned shutdown if there is no bypass, so book it in a low-risk window. Small units: for plug-in single-phase units with an internal battery pack, per-jar readings, connection resistance and capacity tests are usually replaced by the self-test, a runtime check against the manufacturer’s runtime chart and the pack’s age (GDF field note). Run a self-test only when the battery is believed healthy, because it moves the load onto the battery.

MEPPI gives a field example about filters: a UPS on the floor of a dusty, busy room needed its filter changed at least once a month, because caked dust can create new paths for current and even lead to arcing on a circuit board. If your room is dusty, ask your provider to shorten the filter interval; staff should change a filter only where the manual allows it without opening the unit.

What to do when a reading is bad

A checklist is only useful if it says what happens next. Table 3 is GDF’s guidance for the people on site; the limits that decide a replacement always come from the manufacturer’s data and the battery standard.

What a preventive maintenance checklist has to prove

Each line of the checklist must leave evidence someone can check later. MEPPI’s published checklist records display values (bypass input, AC input, battery and battery current, inverter output), reviews the event log and notes battery operation time, then inspects filters and fans and measures the battery. Vertiv’s battery maintenance data sheet lists what it records: total float voltage and charging current, AC ripple voltage and current, ambient temperature, the temperature and float voltage of every jar, connection resistances and all internal ohmic readings, compiled into a report that notes deficiencies and the corrective action needed, taken or planned. Reduced to what a buyer can verify, that is the five points in the direct answer: history captured, UPS measured against its past, every jar measured, software reviewed with care, results written down.

Vertiv’s data sheet calls batteries historically “a leading root cause of data center downtime” and notes that a single bad cell can put the whole backup system at risk. A report that says “battery OK” without per-jar numbers proves nothing.

How often: the intervals the standards set

There is no single legal interval for UPS maintenance in Canada. The manufacturer comes first: MEPPI, for example, says UPS preventive maintenance “typically occurs on a semi-annual or annual basis”. Where the manufacturer gives nothing, NFPA 70B, Standard for Electrical Equipment Maintenance, fills the gap. Its 2023 edition turned it into a standard with mandatory language, and section 9.2.2 applies the intervals in Table 9.2.2 where the manufacturer’s recommendations are not provided or available and a failure would present an unacceptable risk to people or the environment. Table 4 excerpts the rows that matter for a UPS.

“Mechanical servicing” and “special procedures” are task categories as NFPA 70B names them; the manufacturer’s manual says what they involve for a given model. The UPS rows are far tighter than the stationary battery row, so the UPS schedule decides how often someone looks at the system. The battery row is a maximum from the electrical-equipment point of view; IEEE 1188 asks for much more frequent checks of VRLA cells, so the battery plan follows IEEE 1188 and the battery manufacturer (Table 5).

Worked example. A UPS rated Condition 2 because its readings deviate from the previous visit needs a visual inspection at least every 3 months and electrical testing, cleaning and mechanical servicing at least every 6 months, plus infrared thermography every 12 months and the special procedures every 24 months. That is four visits a year: two minor visits and two fuller ones. A Condition 1 unit can meet the UPS rows with two visits a year, a minor visit at six months and a major visit at twelve, but its VRLA battery still needs the two extra quarterly readings described above.

Setting your own interval: the condition method

NFPA 70B section 9.3 rates each piece of equipment. Condition 1 applies when the equipment looks like new, the enclosure is clean, dry and tight, there is no unaddressed notification from continuous monitoring, no active recommendation from predictive techniques, and previous maintenance followed the EMP. Condition 2 applies when maintenance results deviate from past results or the manufacturer’s data calls for more frequent maintenance, the previous cycle required repair or replacement of major components, monitoring has raised notifications since the last assessment, or predictive techniques have active recommendations. Condition 3 applies when changes in operation are noted, the equipment missed the last two maintenance cycles, the last two cycles both required major repairs, there is an active or unaddressed monitoring notification, or predictive techniques identify urgent actions. Figure 1 asks these questions worst case first.

HVM, which publishes a summary chart of Table 9.2.2, adds that the criticality of the equipment to the whole power system should also weigh on the rating. GDF field note: criticality is also why our programs differ by site. They run annual visits for small single-phase units in non-critical rooms, semi-annual visits as the standard for data centres, hospitals and government sites, and quarterly visits for high-availability and mission-critical sites (see our UPS preventive maintenance service). If you only need the standards background, our page on UPS preventive maintenance intervals and standards covers it; this page is the working checklist.

The battery section: what to measure and when

IEEE Std 1188 is the recommended practice for maintaining, testing and replacing stationary VRLA batteries; IEEE Std 450 covers vented lead-acid batteries. Table 5 follows Megger’s summary of the 2005 edition of IEEE 1188. IEEE has since published IEEE 1188-2025, which supersedes it, and IEEE 450 has also been revised since the 2010 edition Megger summarized, so confirm the intervals in the current editions before you write them into a contract. In a new contract, name the current edition (IEEE 1188-2025 for VRLA) rather than the 2005 text.

Worked example of the capacity-test cycle. For a VRLA battery with a 5-year expected service life, 25% of that life is 0.25 × 60 months = 15 months, which is less than 24 months, so the test is due every 15 months. For a 10-year battery, 25% is 30 months; 24 months is less, so the test is due every 24 months. Use the service life the battery manufacturer states for your actual operating temperature; the published design life assumes the reference temperature on the data sheet.

IEEE 1188-2005, section 8, recommends replacing a battery when its capacity falls below 80% of its rating, as a 2008 Battcon paper hosted by Vertiv quotes it; the same paper argues that some large 2 V cells can be recovered first, a decision for the battery manufacturer. A capacity test also leaves the load with reduced runtime until the battery has recharged, so the MOP should say how long that window lasts and what covers the load meanwhile. GDF guidance on reading the other numbers: compare each jar’s ohmic value with its own baseline and with its neighbours, measured with the same instrument and method each time; a rise in impedance or resistance, or a fall in conductance, is a reason to investigate, not proof of lost capacity. Our guide to UPS battery life and how to prove it explains the numbers, and our article on which load bank test to request covers runtime validation.

What happens during a major visit

Readings that need current flowing, such as infrared images, are taken before the load is moved, and history is captured before anything is switched off (GDF field note: some models lose their event history when de-energized). Figure 2 shows the order GDF follows on a major visit; the steps follow the order of MEPPI’s published checklist. FacilitiesNet’s maintenance checklist adds testing of transfer switches, circuit breakers and maintenance bypasses and, where a generator feeds the UPS, a generator test monthly or quarterly.

Steps 5 and 6 carry the risk, and the risks differ. Internal inspection happens with the load on the maintenance bypass, which is raw utility power, or shut down on units without one; all AC and DC sources are locked out, the manual’s DC capacitor discharge time is respected and the absence of voltage is verified. A transfer to static bypass depends on the bypass source being in tolerance and synchronized. An AC input failure test or a self-test moves the load onto the battery and can drop it if the battery is weak. So each belongs in a written MOP with its preconditions, stop points and way back, and a test that is not safe on the day is reported as not performed, with the reason and a new date.

Logs, firmware and settings

The event log shows every transfer to battery, every overload and every fault since the last visit. MEPPI uses battery operation time as an example: when the running total is high, the technician tells the customer to find out why the site keeps losing utility power. Ask for the exported file, not a sentence saying the log was “reviewed”. Our guides to APC UPS fault codes and Eaton UPS alarm codes explain the common entries.

MEPPI describes software updates as “often overlooked” and says they “can provide significant benefits”; it records the site’s specific system values, especially before a software update, because on its systems updates return the system to default values. A checklist should therefore read “record installed firmware, check manufacturer advisories, save the settings, apply the manufacturer’s update when approved”, and the report shows the version before and after and where the saved settings are kept.

Canadian conditions: safety rules and standards

NFPA 70B is American. Its Canadian counterpart is CSA Z463, Maintenance of electrical systems, which specifies requirements for maintaining electrical equipment and systems; its current edition is CSA Z463:24. Workplace electrical safety during the work falls under CSA Z462. Whether either is mandatory for your site depends on your province, insurer and contract, so name the one you want in the contract. In Quebec, the CNESST sets the method: except in exceptional cases, work on an electrical installation is done de-energized with lockout, and energized work is allowed only when the employer can show de-energized work is not possible and has confirmed equivalent safety through a risk analysis (RSST sections 195 to 207; CSTC sections 2.20.1 to 2.20.14 on construction sites). For a UPS, the battery string stays energized after its AC supply is off, so the provider’s MOP must show how every source is locked out. Table 6 sums up which document governs which question.

What the maintenance report must contain

The report is the deliverable. Vertiv’s battery scope ends with a report of deficiencies and corrective actions, and MEPPI sends a field service report after each visit. Table 7 lists the records worth keeping for the life of the UPS; our article on the report format a building inspector expects covers presentation.

What to write into the contract, and red flags

Check each line against the first report you receive.

• Table 1 (or the manufacturer’s equivalent) is attached, with minor and major visits named and dated.
• Each UPS has an interval justified by the manufacturer’s schedule or its NFPA 70B / CSA Z463 condition, reviewed each year.
• Battery work follows IEEE 1188 or IEEE 450 (current edition) and the battery manufacturer: per-jar readings every quarter by visit or monitoring, connection resistance and torque yearly, capacity tests on the cycle worked out above.
• Every report includes the exported log, the per-jar table with trends, infrared images, firmware versions and the tests not performed with reasons.
• Isolation, transfers and capacity tests run under a MOP you approve, stating what protects the load at each step.
• Firmware changes need your approval and a saved configuration; warranty and OEM contract terms are respected.
• Emergency response between visits is defined separately; reports come in the language your team works in (in Quebec, usually French or bilingual).

Red flags in a provider’s checklist: “battery OK” with no numbers; voltage-only battery checks, when IEEE 1188 adds quarterly ohmic readings and a periodic capacity test; “logs reviewed” with no file; “firmware updated” with no version or settings record; self-tests or input-failure tests on every visit with no MOP; the same plan for a clean Condition 1 unit and one that missed two cycles; and reports where no test is ever “not performed”. GDF field note: in fleets we take over, the most common gap is the missing trend. Each report may look fine, but with no previous values beside the readings nobody sees a battery or fan wearing out until an alarm does.

Comparing prices? Our breakdown of UPS maintenance costs in Canada shows what drives the cost of a visit, and our guide to what a real PM visit includes covers brand differences for APC, Eaton, Tripp Lite, Liebert and Delta. When readings show a worn battery, our UPS battery replacement service handles the swap, and our partner store UPSPLUSBATTERY lists UPS replacement batteries for most brands; confirm warranty terms first on equipment still under warranty.

Need a maintenance checklist that holds up to an audit?

GDF Technologies maintains UPS systems of every major brand across Canada, APC / Schneider, Eaton / Powerware, Vertiv / Liebert, Tripp Lite, Mitsubishi and Delta, from single-phase rack units to three-phase systems. Our service page describes a signed report after every visit with photos, measurements, recommendations and a replacement schedule. Send us the model, serial number and your last maintenance report, and we will tell you which condition we would assign, what interval that implies, and what is missing from the current checklist. Contact GDF Technologies, call 514-252-8324 or email support@gdftech.com.

Sources

1. NFPA, NFPA 70B, Standard for Electrical Equipment Maintenance, 2023 edition, section 9.2.2, Table 9.2.2 and section 9.3, as reproduced in HVM, NFPA 70B: Equipment Condition Assessment. UPS, battery and infrared intervals; condition criteria.
2. IEEE Std 1188-2005 (VRLA) and IEEE Std 450-2010 (vented lead-acid), as summarized in Megger, Standard Battery Testing Requirements Summary. Monthly, quarterly and yearly checks; capacity test every 25% of expected life or two years.
3. IEEE Standards Association, IEEE 1188-2005 record, showing it superseded by IEEE 1188-2025.
4. Vertiv, Battery Preventive Maintenance data sheet, CS-00135 (R3/17). Inspection items, measurements recorded, report contents.
5. Battcon 2008, Report on the long term results of battery capacity recovery processes for VRLA cells (hosted by Vertiv). Quotes the IEEE 1188 section 8 replacement criterion of 80% of rating.
6. Mitsubishi Electric Power Products, Inc., What to Expect from UPS Preventative Maintenance Visits. Semi-annual and annual checklist, battery operation time, filter example, software updates and settings, field service report.
7. FacilitiesNet, UPS Maintenance Checklist (updated 2023). Thermal scans, monitored battery rundown test, tests of transfer switches, breakers and maintenance bypasses, generator testing.
8. CSA Group, CSA Z463:24, Maintenance of electrical systems, and CSA Z462:24, Workplace electrical safety.
9. CNESST, Électricité : danger d’électrisation (in French). De-energized work with lockout by default; RSST sections 195 to 207; CSTC sections 2.20.1 to 2.20.14.
10. GDF Technologies, UPS Preventive Maintenance Service. Annual, semi-annual and quarterly programs and the visit report.

All product and company names are trademarks of their respective owners. NFPA 70B is a registered trademark of the National Fire Protection Association. Authored by Christian Barkley, Director, GDF Technologies. LinkedIn: https://www.linkedin.com/in/christian-b-a22619a1/