Thermocable ProReact EN Analogue - Glossary of Technical Terms

Page 26 of 29 Revision 3.3 Feb 2021
ProReact EN Analogue Installation Manual
Document Ref. PACC-MAN
Glossary
Alarm condition – A re or overheat around the Analogue LHD cable which triggers the sensor control
unit.
Pre-alarm condition - An abnormal temperature around the Analogue LHD cable which activates a pre-
alarm signal at the sensor control unit
Cable glands – Used to form a dust-proof and weatherproof seal around a cable entering or exiting an
enclosure.
Analogue linear heat detection cable – A sensing cable where the main characteristic is a predictable
and repeatable change in resistance between at least two cores of the sensor cable. The change in
resistance is monitored by a sensor control unit.
Area/Room protection – An application in which the sensing element is installed at a distance from the
potential re hazard close to the ceiling or roof of the area to be protected (BS EN54-22:2015+A1:2020
section 3.1.10).
Local protection – An application in which the sensing element is installed in relatively close proximity
to the potential re risk (BS EN54-22:2015+A1:2020 section 3.1.5).
End of line unit – A unit which allows a current ow through a circuit to monitor the integrity of the
circuit. In the event of a break in the circuit, current will stop owing completely and a trouble or fault
signal will be triggered.
Fault condition – A break in one or more cores of the Analogue LHD cable or a malfunction of the
Analogue control unit.
Junction box – A secure, dust-proof and weatherproof enclosure to protect a join between two lengths
of Analogue LHD cable or a length of Analogue LHD cable and leader cable.
Leader cable – A non-temperature sensing cable which transmits the signals between two components
in the system, e.g. the Analogue control unit and the Analogue LHD cable. Does not provide re
detection and may be re-rated to continue functioning even in a re condition.
Two-wire RS-485 Modbus RTU/ASCII Communications – An industry standard, signalling protocol used
to communicate information between components in a system, for example a SCADA system or PLC.
Often used to provide more information to be communicated than simple open or closed status
communicated by a relay output.
Zone – A single circuit of ProReact EN Analogue linear heat detection cable connected to a single
ProReact EN Analogue Composite Control Unit.