Who this guide is for
This guide is for clinic managers, practice owners, facilities engineers and procurement staff who are specifying a powered examination table and have been told it has a "battery backup" or "cordless operation". The task is not to pick the largest number on a datasheet, because in most cases there is no comparable number to pick. The task is to convert a vague claim into a testable requirement you can put into a tender and verify on delivery.
It applies to tables with electric height, backrest, legrest or tilt adjustment in primary care, outpatient and specialist examination rooms. It does not cover operating tables, which fall under a different risk and standards regime.
Requirements to define before you look at products
Battery runtime only means something once the duty it must serve is defined. Write these five points down before contacting suppliers.
- What the battery is for. Two very different cases exist: continuing routine patient positioning through a normal working day, and completing a single safe repositioning during a mains failure so the patient is not left stranded mid-adjustment. The second case is far easier to satisfy and is often what a small internal battery is actually designed to do.
- Which movements count. List the axes that must remain available — typically height, backrest and legrest. A table that keeps height adjustment but loses tilt has very different clinical consequences from one that keeps everything.
- The load the movements carry. Specifying runtime against an unloaded table is close to meaningless. State the patient weight the room must support, since actuator current draw rises with load.
- How many cycles per session. Estimate how many full positioning cycles a typical consultation involves, then multiply by a realistic busy session length rather than the average day.
- The electrical environment. Whether the room has protected sockets, whether the table sits on a UPS-backed circuit, and whether the battery is intended as a substitute for, or a supplement to, facility power resilience.
Selection criteria that actually differentiate products
1. A declared test condition, not a bare figure
A credible runtime claim names the load, the movement, the stroke or cycle definition, the ambient temperature and the battery state at the start of the test. A claim of "X minutes of backup" with no conditions attached cannot be compared with a competing product and should not be written into a specification as-is.
2. Actuator and duty-cycle data, read correctly
Powered tables are built on linear actuators and lifting columns, and their technical data normally lists voltage, thrust, speed, stroke and duty cycle — for example, thrust ratings in the hundreds of newtons, speeds of a few to a few tens of millimetres per second, strokes of a few tens to roughly a hundred millimetres, and duty cycles expressed as a percentage of on-time. These numbers describe the mechanism. They do not translate into minutes of battery runtime, and a supplier who converts one into the other without a test has not measured anything. Duty cycle remains useful, though: it tells you how hard the mechanism may be worked before a thermal rest is required, which affects how much of your session the battery must actually carry.
3. Battery chemistry, capacity and replacement path
Ask for the chemistry (sealed lead-acid versus lithium-based), the rated capacity in Wh or Ah, whether the pack is user-replaceable or service-only, and the expected service life in years alongside the replacement part number. A battery whose replacement part is discontinued turns a working table into a fixed-height table.
4. Charging behaviour and state indication
Medical electrical equipment standards treat battery-powered and battery-backed functions as something the operator must be able to monitor, and pre-use checks in a clinic rely on a visible charge indicator and a low-battery warning. Confirm where the indicator sits, whether it is readable at the point of patient contact, and what the table does when the battery reaches cut-off — an abrupt stop mid-adjustment is a clinical risk, not just an inconvenience.
5. Behaviour at mains restoration
Ask what happens when power returns during a battery-driven movement: does the table resume, hold, or require an operator reset? This is a routine event in buildings with intermittent supply and it is rarely documented.
6. Evidence you can audit
Request the test report or internal verification record behind the runtime claim, the standard and edition under which the table was assessed, and a sample of the pre-use check the clinic is expected to perform. If other functions are claimed to meet a particular medical electrical equipment standard, ask for the certificate and confirm the edition and the specific clauses assessed.
Decision checklist
- The clinical purpose of battery operation is written down in one sentence.
- Required movements, patient weight and cycles per session are specified numerically.
- The supplier's runtime claim states load, movement, temperature and start-of-test charge.
- Battery chemistry, capacity, service life and replacement part number are in the quote.
- Charge indicator and low-battery warning are demonstrable on the supplied unit.
- Cut-off and power-restoration behaviour are documented, not described verbally.
- The test report and standard edition reference are attached to the offer.
- Pre-use checks are written into the clinic's equipment routine with a named owner.
Scenario-based options
Single consulting room with reliable mains supply
Battery operation here is mostly a convenience and a safety net for repositioning during a brief outage. Specify a modest, clearly documented backup for the height axis plus an unambiguous low-battery warning, and prioritise a user-replaceable battery over extra runtime.
Multi-room clinic with intermittent supply
Treat the battery as part of the room's resilience plan rather than as a substitute for it. Require backup for all clinically relevant axes, document how many cycles the busiest session demands, and confirm that a partially charged table still completes a safe repositioning rather than stalling.
Mobile or outreach examination table
Here runtime genuinely matters, because charging opportunities are irregular. Specify cycles per clinic day rather than minutes, require the charger to work from the supply actually available on site, and ask for the state of charge at which performance begins to degrade.
Shared or high-throughput department
Duty cycle, thermal rest and battery ageing become the limiting factors rather than nominal runtime. Ask for the manufacturer's guidance on cycles between charges at the department's throughput and for the maintenance interval at which capacity is re-verified.
Questions to ask suppliers
- What exactly was measured to produce your runtime figure, and under what load, movement and temperature?
- How many full positioning cycles does the battery deliver at our stated patient weight?
- Which axes remain operable on battery, and in what order do they become unavailable as charge falls?
- What is the battery chemistry, capacity, expected service life and replacement part number?
- What does the table do at cut-off, and on restoration of mains power mid-movement?
- Which standard and edition was the table assessed against, and can we see the certificate and test report?
- What pre-use check do you expect our staff to perform, and how is it recorded?
- How is capacity re-verified during servicing, and what result triggers replacement?
Limitations of this guide
Public documentation for powered examination tables rarely states battery runtime, and where figures are published they are not produced under a common test condition, so cross-brand comparison from brochures is unreliable. Actuator specifications such as thrust, speed, stroke and duty cycle describe the mechanism and cannot be converted into runtime. No single runtime figure suits every clinical setting, and standards requirements differ by jurisdiction and by the claimed function of the device. Verify the applicable standard edition, local electrical installation guidance and the manufacturer's current documentation for the exact model before committing to a specification, and treat any runtime figure without stated test conditions as unverified.