Reliability Vs Availability

Availability as you may recall is one of the three factors in Overall Equipment Effectiveness OEE. Reliability measures the amount of time a machine performs its intended function without failure.

Reliability And Availability Basics

Simply put availability is a measure of the of time the equipment is in an operable state while reliability is a measure of how long the item performs its intended function.

Reliability vs availability. So we understand that A Highly Reliable Machine is Highly Available Machine too but the converse need not be true. Redundancy is an operational requirement of the data center that refers to the duplication of certain components or functions of a system so that if they fail or need to be taken down for maintenance others can take over. Reliability is how well something endures a variety of real world conditions.

Availability is the percentage of time that something is operational and functional. People often confuse reliability and availability. Some customers choose to exclude scheduled service downtime for example planned maintenance from the Total Time in the.

From the equations availability is derived from the reliability but includes non-equipment factors while the reliability is strictly a function of the equipment failure rate. Availability is the simplest building block of reliability. Availability is a percentage uptime such as 999 over a period of time commonly a month or year Common short-hand refers only to the number of nines.

Increasing availability will invariably increase your OEE and reliability plays into performance improvement as well. Such conditions may include risks that dont often occur but may represent a high impact when they do occur. Compare this with the 2nd line.

This is also referred to as the uptime of a service. Some use it to distinguish system availability from node availability1. Using availability reliability The measurement of Availability is driven by time loss whereas the measurement of Reliability is driven by the frequency and impact of failures.

For two different systems it is possible for one system to be more reliable but less available than the other. The C in ACID but its pretty well entrenched so you just have to keep the audience in mind when talking about availability. This difference causes a lot of confusion just like the C in CAP vs.

The difference between these measures allows for. An item of equipment may not be very reliable but if it can be repaired quickly when it fails its availability. For example five nines translates to being 99999 available.

In other words Reliability can be considered a subset of Availability. Some people use reliable as a synonym for available. This metric describes what percentage of the time service is functioning.

Therefore improving both reliability and maintainability will increase system availability. Equipment02 has lowest Availability 9939 but good Reliability MTBR around 400 Hrs. Availability measures the amount of time a machine is available to be operated.

Reliability is a measure of the percentage uptime considering the downtime due only to faults. Availability is a measure of the percentage uptime considering the downtime due to faults and other causes such as planned maintenance. The Equipment03 in Year 1314 has Availability of the order 9958 but lowest Reliability MTBR of 9557 Hrs.

Lets take a closer look. Some believe that redundancy availability and reliability are one in the same but that is not the case at all. Mathematically the Availability of a system can be treated as a function of its Reliability.

We can refine these definitions by. Availability measures the ability of a piece of equipment to be operated if needed while reliability measures the ability of a piece of equipment to perform its intended function for a specific interval without failure. Both availability and reliability measure the amount of time that an asset is operational although they measure this time in different ways.

Availability Availability can be defined as The proportion of time for which the equipment is able to perform its function Availability is different from reliability in that it takes repair time into account.

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