C
SR 4 GENERATOR
SYSTEMS OPERATION
FLYBACK CIRCUIT
A circuit from the negative (-) end to the positive (+)
end of the exciter field (L3) permits a current flow in' the
exciter field, when the controlled rectifier (CR9) is
"turned off." That is, when (T0) is negative and (T1) is
positive. The flow is as follows:
From the negative (-) end of exciter field (L3)
through wire (F2) to terminal (F2).
From terminal (F2) through wire (6) to spade
terminal (6) on rectifier module (A2).
From spade terminal (6) on-rectifier module (A2) to
the anode (terminal end) of field rectifier (CR10).
From the cathode (stud end) of field rectifier (CR10)
to heat sink (E4).
From heat sink (E4) to spade terminal (8) on rectifier
module (A2).
A2 RECTIFIER MODULE
CR9
Controlled rectifier
CR10
Field rectifier
E4
Heat sink
From spade terminal (8) on rectifier module (A2)
through wire (8) to terminal (F1).
When the current flow goes through exciter field (L3)
it causes a magnetic field around the coils of the field.
The strength of the magnetic field is in relation to the
current going through the exciter field. An increase in
current flow makes the magnetic field stronger, and a
decrease in current flow makes the magnetic field
weaker. When the current through the exciter field (L3)
stops because controlled rectifier (CR9) has cut-off the
flow, the magnetic field strength is maximum. The field
now starts to collapse (grow weaker) back into the
conductors of the coil. As a result of this, a voltage is
induced in the coil. The voltage causes a current flow,
as shown in the circuit schematic. This circuit helps to
keep current flow through exciter field (L3) constant.
END HOUSING
L3 Exciter field
INSIDE GENERATOR HOUSING
L3 Exciter Field
32
