Honeywell 700 User Manual
HONEYWELL MODEL 700/800 SIGNAL PROCESSOR AND VIEWING HEAD
66-2069—02
36
SAFETY MANUAL: S70X & 80X VIEWING HEAD
S702, S706, S802, AND S806
Product Declaration
FIT FOR USE IN A LOW DEMAND SAFETY APPLICATION.
Models: S702, S702-PF, S702-HF, S702-HF-PF, S706, S706-PF, S802, S802-HF, S806
Models
SIL
HFT
SFF
PFD
λ
s
λ
dd
λ
du
S702 and S802
3
0
>99%
1.81 x 10
-10
1.70 x 10
-7
2.27 x 10
-11
0
S706 and S806
3
0
>99%
1.51 x 10
-5
1.02 x 10
-5
2.27 x 10
-11
6.90 x 10
-10
System Architecture
1oo1
MTTR (Mean Time to Restoration
8 hours
Proof Test Interval
5 years
Fit for use in
SIL 3 environment
Table 6. Definitions.
Term
Definition
Dangerous Failure
Failure which has the potential to put the safety-related system in a hazardous or fail-to-function
state.
Safety-related System
A system that implements the required safety functions required to achieve or maintain a safe
state and is intended to achieve on its own or with other systems the necessary safety integrity for
the required safety functions.
Safety Function
Defined function, which is performed by a safety-related system with the aim of achieving or
maintaining a safe state for the plant, in respect of a specified hazardous event.
Proof Test
Periodic test performed to detect failures in a safety-related system so that, if necessary, the
system can be restored to an “as new” condition or as close as practical to this condition.
MTTR (Mean Time to
Restoration)
The average duration required for restoration of operations after a failure.
λ
sd
Rate of safe detectable failures per one billion hours.
For example if
λ
sd
= 3000, then it is estimated that there will be about 3,000 safe detectable
failures during every one billion hours of operation.
For
λ
sd
= 3000, this is about one safe detectable failure every 38 years.
λ
su
Rate of safe undetectable failures per one billion hours.
λ
dd
Rate of dangerous detectable failures per one billion hours.
λ
du
Rate of dangerous undetectable failures per one billion hours.
HFT
Hardware Fault Tolerance
System Architecture
Specific configuration of hardware and software elements in a system.
PFD
AVG
(Average Probability
of Failure on Demand)
Average Probability of Failure on Demand. In this case, regarding the S702, S706, S802, and
S806 viewing heads.
FIT (Failures in Time)
A unit of measurement representing one failure per billion hours. 1,000,000,000 hours is
approximately 114,155.25 years.