Safety Parameters; Proof Test Interval; Special Notes - Honeywell Searchpoint Optima Plus Sicherheitshandbuch

MAN0921_Issue 1_05/12
The Searchpoint Optima Plus safety parameters listed below were provided by TÜV in report
968/EZ 559.00/12.
SFF
> 90%
SFF: Safe Failure Fraction. A percentage of safe failures as compared to all failures
PFDavg: Average probability of failure to perform its design function on demand
PFH: Probability of a dangerous failure per hour

1.1 Proof Test Interval

The purpose of a proof test is to return the unit to "as new" in terms of its safety parameters.
The proof test interval is 1 year.
According to IEC 61508, users are allowed to extend the proof test interval to meet their system needs.
Honeywell allows such an extension, as long as the user follows the proper calculation method for
calculating a proof test interval as defined in IEC 61508 for the desired SIL level. This proof test interval will
vary depending on system, hardware architecture and application.
Note: The proof test interval should not preclude more frequent maintenance of Searchpoint Optima Plus in
accordance with the Operating Instructions if site conditions require it.

1.2 Special Notes

1. The HART Communications and the RS485 link must not be used for safety purposes.
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2. Under a certain extremely rare combination of fault conditions, there is a risk that Searchpoint Optima
Plus could output >100 mA. Should a customer be concerned about this, it is recommended that a
suitable fuse is fitted in the 4-20 mA output line.
3. Searchpoint Optima Plus must be protected from over voltage conditions (i.e. above the supply voltage
specification).

1. Safety Parameters

PFD
2.13x10
avg
-4
3
Searchpoint Optima Plus
Safety Manual
PFH
4.87x10
-8