Consilium PG11 - 5 Operation; 5.1 Function test

Operating Manual PG11 / PGE11 Page 21
5 Operation
During operation there is very little to do with the detector other than performing the regular Function test of
the detector and cleaning of lens and mirror if dirty. The cleaning of lens and mirror is described in the
chapter Maintenance and Function test is explained in the next chapter.
5.1 Function test
Function test of the Detector can be performed by applying gas or using the Gas Free test kit. This is a
simple test carried out to make sure the gas detector will respond when exposed to gas, often referred to as
Bump testing the Detector. This test is typically performed on a regular basis to verify the Safety Functions of
the Detector. The bump test is used to confirm the detector is responding to gas presence and generating
the correct outputs as prescribed. The Operator can select from one of the methods described below
depending on the configuration of the detector and local preferences.
It is recommended to perform the Function test in non-condensing ambient conditions.
Proof Test interval
The time between two periodical tests of the Detector Safety Function is from a Safety context called the Test
Interval. PG11 is certified in accordance with the standard IEC 61508 with a SIL2 rating. If used in an 1oo2
configuration the PG11 is rated for SIL3.
!
A gas being released from a Gas cylinder will give a very small “gas cloud” that will be diluted very
quickly. This is challenging when testing a gas detector since the gas reaching the gas detector will
have a much lower concentration compared to what is on the Gas cylinder. Especially if there are
windy conditions it can be challenging to get any gas to the detector with a small amount of gas
coming from a Gas cylinder. Therefore precautions have to be taken when testing a detector to get
valid results.
For example, using a 50 %LEL test gas and injecting it at 2 liters/min into a PG11 fitted with
Environment Shield using the “ Gas test kit ”, can result in a gas reading as low as 20 %LEL if there is
windy conditions.
Please refer to the chapter “5.2 Perform a check of the Gas Detector accuracy ” if a more precise test
is required.