Intruder alert | Archive Titles

Main wiring techniques
Grade	Technique	Considerations
EN Grade 1	Single Pole	%3Cli%3EDIY/mass consumer %3Cbr /%3Emarket only
EN Grade 2	Double Pole%3Cbr /%3E%3Cbr /%3E%3Cli%3E Two closed loops (circuit conductors) at different polarities %3Cbr /%3E%3Cli%3E Loops provide supervision for 'derection' and 'tamper' at all material time (24hrs)	%3Cli%3ETraditional %3Cbr /%3E%3Cli%3EEasily retrofitted %3Cbr /%3E%3Cli%3EIndividual circuits are used but this reflects in greater cabling run lengths%3Cbr /%3E%3Cbr /%3E
EN Grade 2	End of line (EOL) 2 wire%3Cbr /%3E%3Cbr /%3E%3Cli%3E An EOL device used for the detection loop at the ‘far’ end of the circuit %3Cbr /%3E%3Cli%3E Control equipment analyses impedance	%3Cli%3E A progression on double pole%3Cbr /%3E%3Cli%3E Manufacturers use different EOL values c Cannot be retrofitted easily without changing the wiring at the final device
EN Grade 2 (remote maintenance)	Dual operation Fully supervised loop (FSL) or EOL 2 wire%3Cbr /%3E%3Cbr /%3E%3Cli%3E Resistors are fitted in parallel in the detection device across the contacts%3Cbr /%3E%3Cli%3E May also use series resistors plus EOL	%3Cli%3EProvides full supervision with a reduction in cabling %3Cbr /%3E%3Cli%3E Not easily retrofitted %3Cbr /%3E%3Cli%3E Resistors are supplied by the manufacturer to suit the equipment type
EN Grade 3 %3Cbr /%3E	Triple resistors FSL 2 wire%3Cbr /%3E%3Cbr /%3E%3Cli%3EUse variant value resistors for alarm contact, fault contact and EOL	%3Cli%3EProvides full supervision and fault contact anti-masking and circuit analysis %3Cbr /%3E%3Cli%3E Not easily retrofitted
WN Grade 3 or 4%3Cbr /%3EMultiplex. Data bus. Addressable	%3Cli%3EUse main data highways, branches or node type networks (point in a circuit at which the conductors join to form a junction). iD variations	%3Cli%3ENo requirement to wire each device as a ‘home run’ to the main control point%3Cbr /%3E%3Cli%3EEquipment differs enormously in terms of parameters and system configurations