A Symbolic Analysis of Relay and Switching Circuits

21
Hinderance Function of a Non-Series-parallel Network,
The methods of part II were not sufficient to handle
circuits which contained connections other than those
of a series-parallel type. The bridge of Fig. 11, for
examPle, is a non-aeries-parallel network.
These networks
v'ill lJe
handled by reducing to en equivalent
series-parallel cireuit.
'rhree methods have baen
developed for finding the equivalent of a network
such e s the bridge.
R
s
b
u
v
Fig.
The
first is the obVious method of aPPlying
the transformstions until the network is of the
series-parallel type an d then wr1 t1ng the h1nderan ce
function bv inspection.
This process is exactly
the same a s
is used in simplifying complex impedal1c e
networks. To apply this to the circuit of Fig. 11,
first eliminate the node c, by applying the star
to mesh transformation to the star a-c, b-c, d-c.
This ~i ves the network of Fig. 12.