The SCSI termination power on the DSBE/S SBus card is protected with a positive temperature coefficient (PTC) component. This component acts somewhat like a fuse.
A PTC will sense excessive current and increase its internal resistance to reduce the current to an acceptable level. The PTC will restore a circuit to normal operation once the potentially harmful condition has passed. In contrast, a fuse shuts down a circuit when a harmful condition first occurs, and that circuit remains shut down until the fuse is replaced.
If the PTC component (fuse) on the DSBE/S card shuts down a circuit, do the following:
Figure A-1 DSBE/S SBus Card Components
