Omni8/16C/Omni8P User Manual
UMC1480R24.pdf
70
© Omniflex 2021
7
FUNCTIONAL SAFETY MANUAL
7.1
Function Specification
Omni16C Alarm Annunciator is a product designed to alert the operator to abnormal process or plant
conditions, one or more of which may be safety-critical. The unit has visual indication windows on the front
and all terminals and other connection facilities at the back. Configuration switches are also accessible at
the back of the unit.
When using Omni16C in SIL1 applications, one safety function is defined as change to Alarm state in
response to one input.
Omni16C accepts inputs from field devices. In SIL1 applications an input must originate from contact
which is normally closed and opens on abnormal condition. The contacts can be potential free or use
positive common.
Output is in the form of visual Alarm indication on the front panel which is achieved by flashing a display
window corresponding to the activated input. In normal operation the unit also activates General Alarm
(GA) output in the form of relay contacts and Audible alarm, also in the form of relay contact. These
contacts can be connected to the next logic device in the safety loop.
Alarms can be Silenced, Acknowledged (Accepted) or Reset by means of external pushbuttons connected
to Omni16C terminals.
Diagnostic output is provided by special illumination pattern of alarm windows or opening of watchdog
relay output.
7.2
Hardware Configuration
The SIL1 certification refers to the 24V unit and to the following hardware configuration:
Table 7-1 – Hardware Modules of SIL1 Omni16
Assembly
Quantity
CPU board
1
Logic Bus board
1
Common Services board
1
Input board
2
Display board
1
LED board red
16
Several hardware configurations using the same or smaller set of these modules are possible which have
then different product designations (e.g. Omni8C, Remote Logic Units etc.). However, the safety
parameters remain the same in each case and no reduction in failure rates is assumed on account of
unused modules.
Software is the same in all Omni16C family products.
Safety parameters for additional optional cards are available on request. Their use must be assessed
separately.
