Oldham SharpEye NP40IGB, User Manual, Page: 48 / 50

49
E.1.2 Guidelines for Configuring, Installing, Operating and Service
The alert conditions according to SIL 2 can be implemented by an:
•
Alert signal via 20mA current loop
or
•
Alert signal via alarm relay and the fault relay
E.1.2.1
Conditions for Safe Operating
48
The flame detector shall consist only of the approved hardware and software modules.
49
The 24V power supply must fulfill the requirements for PELV / SELV of EN 60950.
50
The automatic BIT (Built-In-Test) must be activated.
51
The set-up parameters must be verified (as described in Using the 4-20mA Interface
for Alerting on page 49, point 52 and in Using the Alarm Relay Contact for Alerting
on page 49, point 56) and the function of the 40/40 Flame Detector (flame detection,
function of the 4-20mA interface, relay functions) must be checked completely.
E.1.2.2 Using the 4-20mA Interface for Alerting
52
The following parameters shall be set:
•
AUTOMATIC BIT test = on
•
Connected to 4-20mA Terminals
53
The following allowed output current must be supervised with an accuracy of ± 5%:
•
Normal State = 5mA
•
Warning State = 10mA
•
Alarm State = 15mA
54
The output current must be supervised regarding the over-and under run of the 4-
20mA.
55
The 4-20mA can be used as low and high demand mode.
E.1.2.3
Using the Alarm Relay Contact for Alerting
56
The following parameters shall be set:
•
AUTOMATIC BIT Test = on
•
Connected to N.C contact of Alarm Relay Terminals
•
Connected to Fault Relay Terminals
57
The relay contacts (“alarm” – and “faulty relay”) must be protected with a fuse rated
at 0.6 of the nominal specified relay contact current.
58
The maximum contact rating that is allowed per SIL-2 is 30VDC.
59
It is to be considered that the contact of the Alarm Relay opens if there is a fire alarm.
60
During the forwarding and evaluation of the alarm it must be noted that the relay
contact opens.
61
The alarm relay can be used as low demand only.
E.1.2.4
Other
62
The complete function of the flame detector (flame detection, function of the 4-0mA
interface, the relays) must be examined at least every six or twelve months (see
Safety
Relevant Parameters on page 48, when the flame detector must be switched OFF and
ON.
63
The window of the sensor must be examined at appropriate time intervals for partial
contamination.
64
The HART and the RS 485 interfaces must not be used for the transmission of the
safety-related data.