KROHNE OPTISWIRL 4200 Supplementary Instructions Manual page 31

APPENDIX
OPTISWIRL 4200
6
SAC7: Firmware update
Firmware update requires special tooling and can be provided by the authorised personnel of the
manufacturer only.
SAC8: Inspection intervals
Many external events, e.g. environment temperature, may cause the device to age faster than
expected. This has an effect on the failure rate which is assumed as constant over the lifetime at
reference conditions.
Operation
For recommendations regarding the calculation of the proof test intervals refer to
modes and proof test Useful lifetime
on page 19 and refer to on page 29.
SAC9: Modification
A modification may have unexpected influence on the safety function. Such effects must be
analysed. This can only be done by deep knowledge of the internal construction of the device.
SAC10: Repair
Repair of the device exceeding the defined exceptions need more tooling, test and calibration
facilities than available in the field.
SAC12: Supervision of failure current
The preferred failure current is low as it is a state with the lowest energy consumption.
Nevertheless, a failure might prohibit the output of the lower failure current. In that case the
output will be switched to the high failure current.
The failure current (low/high) is configurable but the configuration is only effective in non-SIL
mode. Consequently, a device evaluating the current output must react on both failure currents,
not only on the configured one.
07/2017 - 4005006101 - AD OPTISWIRL4200 SIL R01 en www.krohne.com 31