Nautel XR12 Installation Manual

Also see for XR12: Troubleshooting manual Operation and maintenance manual Preinstallation manual

XR12 Installation ManualIssue 3.0 2009-07-15 Page xiiiMarking hazardsPlace warning signs close to any hazardous areas or systems (e.g., the feedline or the antenna system).Make the signs large enough that they cannot be missed. Provide signage in all languages used in theregion. These signs are intended not only for authorized personnel, but also for emergencyresponders or accidental trespassers.Qualifying site personnelMake sure that personnel who have access to the site are qualified to work around electronics andhigh voltage systems.Ac power protectionYou should take steps to protect equipment from surges (over-voltage spikes) on the ac power lines.Surges may occur during thunderstorms, or because of malfunctions in the electrical distribution grid.Surge suppressors and ac power conditioners can prevent serious damage to your on-site equipment,including the transmitter.RF protectionTransmitters and their antenna systems create intense radio frequency fields at the transmitter site,particularly near the feedline, antenna and tower. At some sites, these fields may cause biologicaleffects, including the heating of body tissues. Intense fields can also create dangerous high voltageson ungrounded, conductive surfaces and objects. At certain points where high voltage conductorscome close to grounded conductors (e.g., at feedline junctions or on the tower), dangerous electricalarcing or flashovers can occur. It is very important that you take the following steps to preventdamage to equipment or personnel due to RF fields:• Use safety interlocks to de-energize transmitters if personnel open doors or panels accessinghigh field areas• Place warning signs in any locations where high fields can occur• Train personnel about the short-term and long-term hazards of RF radiation• Physically block access to the area around the antenna system, feedline and tower• Ground all exposed conductive surfaces or objects in high field areasThe RF connection to the transmitter output can be a serious safety hazard. Connect a 50 Ω test loadduring installation and commissioning. It is recommended that a switch be used to automaticallyconnect the transmitter to the antenna system without human contact with the transmittingconductors.