Constant current power feed equipment - has two wire feed and one wire return with centre-tapped induction coil balance plus branching facility

摘要

A constant current power feed system using a three wire line is used to power intermediate amplifiers at points along the line. The design is applicable to powering intermediate amplifiers in a cable t.v. system, can power feed a branch feeder line, and although feeding a high current is symmetrical so that it is safe against inadvertent contact by a person. The constant generator (1) provides in phase and identical current output to two power feed wires (a and b at 11 and 12), io. The third wire is the return (c at 13) and carries 2io. The power consuming equip. (41-44) are in either of the power feed wires (1, b) of the three wire system (5). The distant end of the circuit is terminated with a centre tapped inductance (2) to preserve circuit symmetry, with the return wire connected to the centre tap. To power a branch feeder (5') the retrn wire can be broken (3) to accept the connection from the branch.