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Here's an old email I sent to Don a couple of years ago entitled "Cell Tower Infrastructure"...
Recently I read on EW.com one of your friends wondering about the infrastructure of cell towers. The company I work for was in the past contracted to provide mechanical and electrical systems designs for some of the small buildings that support cell towers. Please donít hold it against me, as Iím not in a position to pick and choose what jobs our company works on. Besides this was in the past and long before I knew about the dangers these towers pose. I donít know how much of this is relevant or useful to your friend, but I thought Iíd pass along what follows as some potentially useful intel.
What follows is related to the electrical service and distribution to a particular support building.
The current transformer (CT) is an 800 ampere, 3 phase, 4 wire outdoor type cabinet. Downstream of the CT cabinet is the service switch and transient voltage surge suppressor (TVSS). The service switch is a heavy duty, 3 pole, SN, 600 volts, fusible type with a short circuit rating 200,000 RMS amperes with class L fusing. The TVSS has 200KA surge capacity configured as 208Y/120V, 2 phase, 4 wire and ground. The service is backed up by a diesel-fired emergency generator rated 125KW/156.25KVA, 208Y/120V, 3 phase, 4 wire.
The main distribution panel is a 600A Ė 208Y/120V-3 phase-4 wire MDP, which serves, besides some HVAC equipment, 8 electrical panels. Of these 8 panels, 3 are dedicated to transmitter circuits only. Each of these 3 panels is a 42 pole, 208Y/120V-3 phase-4 wire, 150amp main circuit breaker with equipment ground bus. Each transmitter circuit is a 1 pole, 20 amp trip, 1440 load VA, with 2#12 branch circuits. The first of these three panels has 32 circuits dedicated to transmitters. The second has 24 circuits for transmitters and the third has 20 circuits for transmitters with the rest of the panels being space only for future expansion. There is one panel for lighting, receptacles and other small loads. And the remaining 4 panels are 12 space spare 100 amp panels.
Iím not well versed in things electrical and couldnít much explain what any of the foregoing means. But your friend, or some in your network, or among your readers might be able to analyze this information with regard to the capacity of such systems to deal out DOR.
For what itís worthÖ
"This seems to me to be rather excessive. Watts = Volts x Amps Therefore, 240 volts x's 800 amps = 192 Kilowatts per hour x's 3 phase = 576 KWH. Transmitters at microwave frequencies normal only require a max of 1.0 watt, not kilo watts. If this is true then there is covert agenda going on. This type of supply and fusing system will be mega expensive. I don't know what to say, except run for the hills. Power is a square law, i.e. Amps (squared) x's Resistance in ohms. So if you double the voltage you square the power. Nasty."--Electrical engineer