Robot SLAs

Writing an availability target that holds up

The International Electrotechnical Vocabulary defines availability, in entry 192-01-23, as the ability to be in a state to perform as required under given conditions. An SLA has to turn that idea into something measurable. State the hours that count, such as your scheduled operating shifts, and list what is excluded, typically agreed maintenance windows and stoppages caused by your own staff or systems. Name the data source that will decide the figure, whether the robot's logs, the provider's monitoring or your own production system, and say who can see it. Set the reporting period too, because a monthly average can hide one terrible week. Decide in advance how a robot running in a degraded mode is scored.

Response time is not restoration time

Some contracts promise a fast response and say little about when the robot will work again. The vocabulary separates the two: entry 192-07-06 defines time to restoration as the interval from the instant of failure until restoration, and notes that where the moment of failure cannot be determined, it runs from detection instead. Build your SLA around a sequence of targets, each with its own clock: acknowledgement of the call, start of remote diagnosis, arrival of an engineer on site where needed, and restoration of service. Set them by severity, so a stopped production line gets faster targets than a single robot running slowly. Make sure the clocks run during your operating hours, not only the provider's office hours.

Service credits and other remedies

Targets without consequences are only aims. A common remedy is a service credit, a reduction in the next invoice when a target is missed, often on a sliding scale by how far performance fell short. Credits are normally capped, so check whether the cap still leaves the provider with a reason to fix things fast. Add remedies that matter more than money: a recovery plan after repeated misses, escalation to named senior contacts, an extra engineer or a substitute robot at the provider's cost, and a right to terminate if targets are missed persistently. Ask how credits are claimed, because some contracts require you to apply within a short window and forfeit them if you do not.

Fitting the SLA into the maintenance contract

An SLA sits inside a wider maintenance or service contract, and the two must agree. BS EN 13269:2016, the European guideline on preparing maintenance contracts, covers the contract framework, the service options and how they are delivered, competence requirements for people and organisations, service outputs, and procedures for disputes and contract changes. Its stated aims include fewer disputes and easier comparison between agreements. Use that structure as a checklist: who does what, with which skills, to what output, and how disagreements are settled. Then attach the SLA schedule with its definitions, targets, measurement method and remedies, and hold a regular review where both sides go through the figures and any changes to the fleet or site.

Sources and further reading

• IEV 192-01-23: availability — Electropedia, International Electrotechnical Commission.
  The IEC's standard definition of availability, a sound starting point for SLA wording.
• IEV 192-07-06: time to restoration — Electropedia, International Electrotechnical Commission.
  The IEC definition of time to restoration, including when the clock starts if the failure time is unknown.
• BS EN 13269:2016 Maintenance: Guideline on preparation of maintenance contracts — BSI.
  European guideline on structuring maintenance contracts: service options, competence, outputs and disputes.

Common questions

What uptime should a robot SLA guarantee?

There is no universal figure. Base the target on how much downtime your process can absorb, the provider's track record with similar robots and the redundancy you have on site. A higher target usually costs more, so ask the provider to price two or three levels before you choose.

Who measures uptime in a robot service contract?

Agree it in writing. Many contracts rely on the provider's monitoring data, but you should have access to the same data and the right to challenge it. Where you can, check the provider's figures against your own production records each month.