IBM 80 Customer Engineering Manual page 48

48 CARD SORTING MACHINE, TYPE 75
control of card lever contact 2. This permits· automatic
operation of the machine as soon as the cards have
reached a position to close card lever contact 2.
Card Control Relay
This relay is a duo relay. (On older machines, this
relay is a high speed slate base relay.) Its primary
function is to prevent starting of the machine by any
means other than the start key. This relay is picked
when the start key is depressed and remains energized
as long as cards are feeding through the machine.
The AU card control relay point, in conjunction with
the B point of card lever relay 2, completes a hold cir-
cuit
to
the card control relay and the motor relay. In
its
N/O
condition, it prevents the energization of either
of the above relays except by means of the start key in
the event the machine is stopped with cards in the
feed.
The AL card control relay point maintains a hold
circuit to the transfer setup relay in the event the
machine is stopped when a card or cards are at the
reading station and the contact roll cover is raised.
Dropout of the transfer setup relay under the above
conditions could cause the reject counter to over count
one in error when the machine was restarted.
The BU card control relay point, in its
N/O
condition,
prevents back circuits which would make the contact
roll hot if the machine was stopped with cards in the
feed and the contact roll cover was raised.
Brush Control Relay
This relay is a high speed slate base relay. Its pur-
pose is
to
provide a holding circuit through its contact
point for the sort magnet from the time an impulse
is sensed through a hole in the card until the end of
the card cycle when the circuit is broken by means of
the commutator center ring and brush.
Card Lever Hold Relay
This relay is a duo relay. Its purpose is to control
the sorting and counting circuits in conjunction with
commutators 1 and 2. This relay is picked and dropped
each card cycle under control of commutators 1 and 2.
The
AL card lever hold point, in its
N/O
condition,
prevents a circuit to the contact roll before the first
card in the machine has insulated the card brush from
the contact roll. In its closed position, this point allows
completion of circuits to the cont'3.ct roll through com-
mutator 2.
The AU card lever hold relay point prevents a back
circuit which would allow the contact roll to be hot
if
the machine
~re
stopped with cards in the feed
and the contact roll cover were raised.
The BL card lever hold relay point prevents back
circuits which would allow the contact roll to be hot
when the contact roll cover was raised (card count
switch on).
Counter Relays 12 through 9
These relays are high speed slate base
rel~ys.
There
is
one relay for each digit counter magnet, 12 through
9. The purpose of each of these relays is to provide a
holding circuit for its particular counter magnet from
the time an impulse is sensed in the card until the
counting commutator for that position breaks the cir-
cuit.
Transfer Set Up Relay
This relay is a high speed slate base relay. Its pur-
pose is
to
determine whether or not any punching is
present in the card column being sensed. If punching
is present, this relay is picked and, in turn, sets up
circuits which prevent impulsing the reject counter. If
no punching is present in the card, the transfer setup
relay is not picked, and the reject counter magnet is
impulsed to add one.
Count Control Relay
This relay is a duo relay. Its A point controls the
circuit to impulse the reject counter magnets. If punch-
ing is present in the column being sensed, the count
control relay is picked under control of the transfer
setup relay and commutator 3, thus interrupting the
circuit to the reject counter. If no punching is present
in the column being sensed, the count control relay
is not picked and
~
circuit is completed through its
N/C
A point to permit energization of the reject counter
magnet.
Commutator
Upon starting of the machine, this commutator pre-
vents completion of a circuit to the contact roll until
the first card has insulated the card brush from the
roll. Commutator 1 also furnishes the timed impulse
to pick the card lever hold relay at the beginning of
each card cycle and, when necessary, furnishes a hold
circuit for the transfer set up relay until commutator
2 makes.
Commutator 2
This commutator continues the circuit to the con-
tact roll for the duration of the card after commutator