Library of Congress Cataloging-in-Publication Data. Petruzella, Frank D., author. Programmable logic controllers / Frank D. Petruzella.—Fifth edition. LogixPro PLC Manual for Programmable Logic Controllers [5th Edition] 9781259680847. Lab book for "Programmable Author / Uploaded; Frank D. Petruzella. Programmable Logic Controllers Fifth Edition by Frank D Petruzella. Preview Programmable Logic Controller/PLC Programming/PLC Direct/PLC/PLC Control. Power and Logic sections. 18. Senses when a signal is received. Converts the input signal to the correct voltage level. Isolates the PLC from the input