CURRENT SENSING - IMPROVED VOLTAGE REGULATION KIT (SC MACHINES ONLY) The standard machine is voltage sensed and if required current sensing can be added to make the machine more flexible to improve the voltage regulation where semi-conductor or thyristor loads are used which distort the voltage waveform of the machine.  This unit can also be used to impact on the sensing circuit of the A.V.R. to overcome voltage drops where long  cables  between  the  generator  and  load  are  used.    The  unit  consists  of  a  current  transformer  C.T.    and  burden resistor.  See Fig. 20. The components are identical to those used for the quadrature droop kit for Parallel Operation, the only difference is that the circuit is arranged to be more sensitive between unity to 0.8 p.f.  (lag) loads. NOTES: 1.  Depending on machine type, one or more main stator cables  are  connected  to  each  output  terminal,  insert improved  regulation  C.T.    on  one  cable  only.    See Fig. 21 for C.T.  position and wiring diagrams. 2.    Connect  to  auxiliary  terminals  2  -  8  (after  removing link)  on  two  phase  sensed  machines  and  4  -  7  (after removing link) on three phase sensed machines. A.V.R. Stator Connection Improved Voltage Type (Standard phase rotation) Regulation Fig. C.T.  Position Two Phase 4 Wire & 6 Wire Star 20 V2 Series Star 20 V2 Sensed 12 Wire Series Delta 20 V2 Parallel Star 20 V2 Series Zig-Zag Star 20* W2 Three Phase 4 Wire & 6 Wire Star 20* V2 Series Star 20* V2 Sensed 12 Wire Series Delta 20* V2 Parallel Star 20* V2 Series Zig-Zag Star 20* U2 Fig. 21 Improved Regulation C.T.  Positions NOTES: 1.   *For these stator connections the C.T.  secondary leads S1 and S2 must be reversed for correct machine operation. 2.   Standard  phase  rotation  is  U.V.W.  when  a.c.  generator  is  rotating  clockwise  viewed  at  the  drive  end.    For  phase rotation U.V.W.  when rotating anti-clockwise refer to factory for details. Resistance Values Burden Resistor - 1000 ohms C.T.  Secondary - 16 ohms 39