Some Basic Things for the cable tray installation: Grounding of cable tray with IGB (Internal Grounding Bus Bar). Distance between cable tray & roof of shelter is Depends on the dimension of Hatch plate. Cable tray should right below the hatch Plate. Drills are made on the shelter walls or roof to provide support for Horizontal Cable Tray. After marking the drilling holes, the ladder is fixed using supporting clamps. Cable Tray forms a major part of installation work since all the Grounding,Power,E1,IF & RF Cable routing is done over this Cable tray.
Cable Tray forms a major part ofinstallation work since all theGrounding,Power,E1,IF & RF Cablerouting is done over this Cabletray.
Grounding Bar Installation:There are two types of grounding bars- External Grounding Bar (EGB) Internal Grounding Bar (IGB)
Some Basic Things for Grounding Bar installation: EGB and IGB both are installed right below the hatch plate, and both are connected to each other by double connection of 35 mm square grounding cable. EGB (External Grounding Bar) is directly connected by the Earth Pit by the GI strip. IGB (Internal Grounding Bar) which is installed inside the shelter room, this is made up of GI strip. EGB (External Grounding Bar) which is installed on the out side of shelter, This is totally made of Copper strip. Every indoor equipment should be grounded through IGB. Then crimp and fix the Lugs at both ends of above these three types of cables & wrap with insulating tape with same color of cable. Grounding resistance of working ground, Protection ground and lightening arrester should be not more than 5 Ω. (Recommended range 0.5 Ω to 5Ω for working ground &1-5 Ω for protection ground).
Battery Bank Installation: In Telecom BTS site 48 volt DC battery bank installed. there are 24 cells in each Battery Bank each is having the 2 volt DC. These battery bank are installed on stand and grouted in the shelter properly. These battery bank have certain distance from the SMPS and we should try to keep O/P of each terminal is in opposite direction of SMPS. Grounding of Battery bank is done with the IGB by the 35 mm square grounding cable & connected to EGB (Internal Grounding Bar).
SMPS INSTALLATION: SMPS is installed nearby the Shelter Door. Battery bank directly connected with the SMPS. SMPS is the DC supply source by which all the equipment inside the shelter is connected like BTS and MW Rack. It charges the battery bank by the AC supply, There are modules which converts AC supply to DC supply. In absence of AC supply it gives the supply by Battery Bank to equipments. It Should be grounded on two points One is on positive bus bar and one is with the body of SMPS with the 35 mm square grounding cable.
SMPS GROUNDING: Positive Bus bar grounding Body grounding
BTS Installation: The BTS installation position should be consistent and must be as per shelter layout design. Now mark the position of BTS base bolts position at ground & do the grouting of Bolts. Then fix base of BTS into grouted bolts also check the leveling. BTS, Microwave rack, DDF box and all the equipment except power equipment are installed on the same side right in front the power equipments. BTS should be grouted properly.
SURGE ARRESTER INSTALLATION: Surge arrester are high frequency protector, these surge arrester protects the BTS from the lightning. These surge arrester fix on the surge arrester stand and this surge arrester stand grounded with EGB. Surge Arrester Stand Surge Arrester
JUMPER CABLE CONNECTION ON BTS: Jumper cable connects on the BTS top. All feeder of three sector connects by the jumper cable. Feeder connects by the jumper via Surge Arrester.
Power cable connection On BTS: BTS power cable blue one connects with the negative bar which is right in front the SMPS via the particular rating of fuses. And positive bus bar connect with black wire of BTS terminal. This negative blue cable connects with the negative terminal of BTS and black one connects with the Gnd of BTS.
Out Door Installation: GSM Antenna Installation on the Tower. Feeder cable Installation and routing. Earthing of Feeder cable. Connection of Jumper cable to Feeder on GSM antenna end. Connection of Jumper cable to Feeder on BTS end.
GSM Antenna Installation on the Tower: GSM Antenna installed on the tower according to the RF plan. The orientation (Azimuth) of the GSM antenna should be according to network plan. GSM antenna also have the tilt by which the coverage area can be increased or decreased, it is also according to plan. Tilt may be zero, two, three or four degree. GSM antenna clamp should be tightened on the tower properly, it should be not loose.
Feeder cable Installation and routing: Feeder cable ( 7/8”) connects with the BTS and GSM antenna. It is connected with BTS and GSM antenna via the Jumper cable. Feeder cable should be routed on the tower by Dummy clamp. In feeder cable installation feeder cable should not be bend more then 90 degree at certain point. Feeder cable routing Bending is not more then 90 degree
Feeder cable comes in the shelter andbefore entering in the shelter it takes a“U” drop. Due to this U drop the waterdo not go inside the shelter. So wemust take care about this U drop justbefore the entrance in shelter. U drop of Feeder
GROUNDING OF FEEDER CABLE:• Feeder cable should be grounded on three points. Two on the tower and one with the EGB.• Grounding is very necessary and it must be on three points.• Grounding is done by the Grounding kit and it should be properly shield with weather proof.
Connection of Jumper cable to Feeder on GSM antenna end:• Feeder cable connects with GSM antenna by the jumper cable ..• Connection should be very tight and shield with weather proof.• Weather proof should be properly done, if it is not proper then this may be on of the reason of VSWR. Weather proofing on GSM and jumper cable on Tower
Connection of Jumper cable to Feeder on BTS end: Feeder cable connect with BTS by the jumper cable. Between jumper and feeder surge arrester should be connected Feeder Cable Surge Arrester Stand Jumper cable
Precaution: Connection of each power cable should be proper. Before switching on the BTS we should check the Input voltage on the BTS terminal by the Multimeter, If it is ok then we should switch on the BTS. We should visually check the Grounding connection of each equipment. All equipments inside the shelter must be grouted. At the time of connection of power cable to Battery Bank we must take care about the safety.