VESDA VLC, Руководство по обслуживанию

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VESDA VESDA Maintenance Guide
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6 Post-maintenance testing
Post-maintenance tests should be performed, after a maintenance visit, to determine whether the system is
functional. Take the appropriate measures to ensure that this testing does not result in unwanted intervention
from response systems, for example, suppression.
Consult your local code guidelines to establish the following:
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The minimum testing required per sampling pipe.
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The appropriate alarm threshold per sampling pipe.
Here are some examples of possible tests:
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You could create a fault to ensure that it is registered by the detector and monitoring system (for example,
remove a pipe to create a high airflow fault).
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You could inject smoke into the last sampling hole to see whether it is detected.
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Likewise, you could inject smoke into critical sampling holes to see whether it is detected.
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More specifically, you could inject smoke into sampling holes only in sections of the pipe network where
maintenance has been performed to check the effectiveness of that maintenance.
With all smoke injections, you need to record transport time, ensure that a significant amount of smoke is
registered and that alarm(s) are generated. The alarm thresholds and amount of smoke injected may have an
impact on the results. You should compare times with the ASPIRE design files, commissioning tests and
service history.
Note: Transport time is the time taken (in seconds) for the smoke to travel to the detector. Typically,
allowing for small variations, the result should be approximately the same as the ASPIRE
calculations.
In the event that there is a wide variation between the ASPIRE results or original commissioning results and
the actual smoke test results, you must investigate the following:
1. Check that the sampling pipe network matches your ASPIRE design.
2. For detectors that support variable aspirator speeds, check that the aspirator speed matches your
ASPIRE design.
3. Check for any preset alarm delays.
4. Check the sampling pipe network for leaks and blockages.
Xtralis does not recommend the use of canned smoke to perform post-maintenance tests. However, if you do
use canned smoke, you should ensure that you do the following:
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Read and carefully follow all instructions on the canned smoke product.
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Take all necessary health and safety precautions.
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Avoid inhaling the fumes.
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Avoid spraying the canned smoke directly into the detector or the pipe inlets.
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Avoid prolonged bursts - use in short bursts of less than 2 seconds.
Prolonged use of canned smoke can damage plastic components and the detector itself, thereby invalidating
the detector's warranty.