Oldham OLC 100, Руководство пользователя

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Annexe – Ordering information 57
The safety function of the OLC/OLCT100 detector is the detection of flammable
gases using catalytic technology and a 4-20 mA current output proportional to the
gas concentration expressed as a percentage of LIE, respectively from 0 to 100%
LIE. In the event of failure, the current will assume a fall-back value less than or
equal to 1 mA or greater than or equal to 23 mA.
The safety function is no longer valid:
❧
After power has been switched on, while the measurement sensor is
stabilizing and during start-up tests, the output current shall be in
maintenance mode (2 mA).
❧
When the push button is pressed (forcing the current to 4 mA), the output
current will be frozen at 4 mA.
Reliability data
These data are based on feedback from experience in the field. The analysis of
the information recorded during maintenance by our technical team has enabled
us to determine the following Probabilities of Failure on Demand under normal
conditions of use:
Type of gas Measurement
principle
SIL
Capability
λ
DU
PFD
AVG
Test
period
SFF
LEL
Catalytic(C1000) SIL 2 2,19 10
-6
2,39 10
-3
3 months
60% to
90%
LEL CO2
Infrared SIL 2 0,13 10
-6
0.35 10
-3
12
months
60% to
90%
Oxygen Electrochemical SIL 2 0,74 10
-6
0.81 10
-3
3 months 60% to
90%
CO Electrochemical SIL 2 1,09 10
-6
1,19 10
-3
3 months 60% to
90%
H2S Electrochemical SIL 2 2,98 10
-6
3,26 10
-3
3 months 60% to
90%
NH3 Electrochemical SIL 2 4,48 10
-6
4,91 10
-3
3 months
60% to
90%
Detector in intrinsically safe "ia" protective
mode: Special use conditions
The detector must be powered by an intrinsically safe source.
The detector input characteristics on the J3 power plot are:
Ui = 28V, Ii = 93.3 mA, Ci = 39.2 nF, Li = 0
Ci = 2.39 µF with Ui = 10.5V, Ci = 4.32µF with Ui = 8.6V