ENMET LC-8 - Manual (Page 7)

LC S ERIES ENMET
5
3.0 Wiring the LC Series
The electrical installation should conform to appropriate electrical codes, such as the National Electrical Code in the United
States.
W ARNING : The compliance of the installation to appropriate codes is not ENMET’s responsibility.
3.1 System Wiring
All connections should be made according to the appropriate sensor or loop diagram for the configuration required. It is advised
that ‘Bootlace Ferrules’ or ‘flat blade crimps’ be used for tidy and reliable connections of wires into the Control Unit and
Detector Head connectors
Power Supply Input
An isolating switch should be provided between the power source and the MCU control units to allow the supply to be easily
disconnected. This should incorporate over current protection or a circuit breaker. Alternatively a fused supply would suffice
AC Mains Connection
The power supply board has three screw terminals connector assigned for the connection of an AC supply.
Pin 1 = Earth
Pin 2 = Live input
Pin 3 = Neutral input
Recommendation for mains input cable. 3-Core – 16 AWG Conductors having cross sectional area of 0.75mm 2 minimum
(24/0.2)
DC Voltage Connection
The power supply board has two screw terminals assigned for the connection of a DC supply
Pin 4 = +24V DC input
Pin 5 = 0V DC input
Cable Routing
Due to the low signal levels generated by gas detectors it is recommended that all wiring to the sensors by segregated away
from AC mains or other high voltage/power lines to avoid interference.
Cable Screening
The use of a screened cable is recommended for the installation of all detector heads. The screening is used to minimise the
effects of electrical interference generated by external equipment e.g. motors, switchgear etc. The correct strategy for
connecting the screens depends upon the area in which the detector head is to be used (i.e. hazardous/ non-hazardous). In all
cases the screen should not be connected at the detector head