MAN0905_Issue 7_07/17
Searchpoint Optima Plus with optional HART
®
output
Operating Instructions
2108M0550
79
15. Specifications
Calibrated against EN60079-20-1:2010 LEL levels
Table Number
Table Name
CAS Number
Full Scale
LEL (%V/V)
ATEX Performance
Approved
Standard Gases
D3240
Ethylene
74-85-1
100%LEL
2.3
Y
Special Gases
D3227
Benzene
71-43-2
100%LEL
1.2
D3229
Buta-1,3-diene
106-99-0
100%LEL
1.4
Calibrated against EN61779 LEL levels
Table Number
Table Name
CAS Number
Full Scale
LEL (%V/V)
ATEX Performance
Approved
Standard Gases
D3228
Styrene
100-42-5
100%LEL
1.1
Note: For other gases, solvents and vapours, contact Honeywell Analytics.
Note: The choice of LEL value should be in accordance with local regulations.
15.3 Cross Interference to Other Gases and Vapours
Searchpoint Optima Plus is supplied pre-calibrated and ready for installation. The signal output
configuration, gas and range for which the unit is calibrated are indicated on a label attached to the main
housing.
Note: The following information is only applicable when detecting Hydrocarbons.
A Searchpoint Optima Plus calibrated for a particular hydrocarbon will have a response to most other
hydrocarbon gases. The cross-sensitivity figures below are approximate and are for guidance only.
The approximate amount of gas required to give an output equal to 50% LEL methane, on Searchpoint
Optima Plus calibrated for 100% LEL (LEL = 5 %v/v) methane is: -.
Methane
2.5 %v/v
Propane
0.3 %v/v
Butane
0.2 %v/v
Hexane
0.3 %v/v
Heptane
0.3 %v/v
Propylene
0.8 %v/v
The following gases are known to produce a negative response from Searchpoint Optima Plus: -
• Ammonia
• Acetylene
• Propyne (Methyl Acetylene)
As a guide, the approximate concentrations that will create a Fault condition in a Searchpoint Optima Plus
calibrated for methane are: -
Ammonia
~ 5500 ppm
Acetylene
~ 1000 ppm
Propyne (Methyl Acetylene)
~ 1000 ppm