Specifications

2.4.8 Shuttle Matrix Motor Control (SMMC)
The SMMC is located in the card cage on the right side of the printer.
It provides circuits necessary to operate the ribbon weld detector, and to
run three motors in the printer; the shuttle motor, the paper motor, and
the ribbon motor.
This board also controls the fans. The rear fan is switched to high during
printing and low when not printing. The front fan is switched ON when
printing and OFF when not printing. The front fan is switched OFF
when the shuttle is stopped (standby) to ease paper loading and reduce
standby noise.
The SMMC powers the shuttle motor, maintaining the motion sine wave
at a fixed amplitude. It uses signals from the interlock switches and LVT
to stop the shuttle motion, and senses and informs the printer logic if
the shuttle becomes mechanically jammed. If the printer logic fails to
respond to this information, the shuttle motor is shut down through an
internal crowbar circuit.
2.5 Power Supply
Figure 2–5 shows a simplified block diagram of the power supply.
2–12 THEORY OF OPERATION