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00238
Gas Detection
Gas Detectors
IMPORTANT - Gas Detectors should not be installed until all building, construction or painting work etc.. Is completed, as these
works can effect the sensitivity and longevity of the detectors.
Ensure that the protective cover labels (
RED
) are removed only
after the completion of all building work and the system has
been commissioned by the Medem engineer.
The labels are required to be removed for the detectors to
operate, but removal before the completion of works risks
contaminating the sensor element.
The system is capable of operating a mix of up to 16 detectors (additional power pack may be required) of different types.
The detector types are:
•
Carbon Dioxide.
•
Carbon Monoxide.
•
Combustible gases (Methane, Propane).
•
Oxygen depletion and temperature.
Detector location will vary dependant on the individual characteristics of the target gas that is being monitored for. See the gas
detectors own instructions for more guidance.
The maximum cable length between a detector and the control panel should not exceed 100 metres, whilst we would always
recommend using screen cable if the distance between the main panel and the detectors is greater than 20metres a 1mm
screened cable must be used on the +VE, 0v terminals
Gas detectors, require a four core screened Belden type security cable or 600v rated BMS cable (max cable length of
100meters.)
Remote emergency stops and thermal links require a two core screened cable.
Warranty will be void if Fire Protection Cable or cable over 1mm dia. is used on the SELV side.
Detector Information
+VE supply & Comm’s
From either the main panel or an
extender.
Detectors are wired in parallel and can be
connected to one another daisy chain
Address Selector
Each detector must be set to its own
address and then “learnt” using button
(23, see page 5)
Connection and addressing
Status LED
SEC-L
v4
When addressing gas detectors CO &
CO2 detectors must be numbered
before natural gas detectors.
