User manual

Digital Monitor AMC-1DBx Series User Manual
89
8 INSTALLATION TIPS AND TRICKS
8.1 CABLING
• The Communications Cable must have the following characteristics;
o Shielded, twisted pair, 12-24AWG
o Characteristic Impedance:120ohms
o Low Capacitance: ~13pf/ft conductor to conductor and ~ 23pf/ft conductor to
shield
• The recommended Power Cable is 12-24 AWG
o Selected cable must meet Application and/or local regulatory requirements.
o Wire gauge will affect maximum distance between transmitters and power
supply. Thicker wire, greater distance.
o Route cabling in conduit to avoid damage to cabling.
• Route cabling in conduit to avoid damage to cabling.
• The communications cable shield must be grounded at the monitor end. The shield is
wired to the T-connector at each transmitter, to maintain end to end continuity.
• Route cabling away from AC power cabling and any source of electro-magnetic
interference (EMI) or radio frequency interference (RFI) such as power transformers,
electric motors, etc.
• EMT (Electrical Metal Tube) conduit also adds an added degree of electrical shielding
against EMI (Electro-Magnetic Interference) from devices such as RF (i.e. radio)
sources.
• All cabling must enter the sensors and monitors from the bottom to ensure protection
against water damage due to water inside the conduit from condensation or leaks.
• Ensure that there are no short or open circuits in the sensor cabling.
• Verify that there is no AC or DC voltage present on the sensor cabling prior to
connecting the cabling to either the sensor or the monitor.
8.2 EQUIPMENT LOCATION
• Mount all equipment away from any source of electro-magnetic interference (EMI) or
radio frequency interference (RFI) such as power transformers, electric motors, etc.
• Mount sensors in accordance with the installation guidelines for the specific species of
gas to be detected; i.e. CO sensors should be mounted at breathing height etc.
• Equipment must be positioned such that the chance of water damage is minimized; i.e.
away from fire suppression sprinkler heads, away from wet or damp locations where
there would be a risk of water damage.
• Ensure a balanced layout of sensors in order to cover the intended area.
• Ensure that sensors are not in close proximity to clean air sources.
8.3 POWER AND GROUNDING
• All power and grounding connections to equipment must be made in accordance with
applicable electrical and building codes.