Upload
luke-banks
View
228
Download
1
Embed Size (px)
Citation preview
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
TIMERSWhen and how to
use them
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
In process controls the timing is often really important; a stable time basis is necessary to sincronyse all the steps of signalling plants (e.g. traffic light plants)
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
Traffic light simulation system
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
it is sometimes possible to measure a quantity, controlling the length of time the action requires (e.g. the radius lift arm which takes the inert materials necessary to produce concrete)
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
Radius lift arm
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
it is sometimes necessary to verify that a certain action is over within the given time or to stop it (time out alarm)
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
Automatic gate
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
TIMERS are tha macro instructions available in every PLC (programmable logic controller) in order to control the processes mentioned before.
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
S_VIMP = timer typeS = set inputTW = time constantR = reset inputT no. = timer numberQ = output timerDUAL = time missing to the end, in Binary codeDEZ = time missing to the end, in BCD code
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
S_EVERZ = timer typeS = set inputTW = time constantR = reset inputT no. = timer numberQ = output timerDUAL = time missing to the end, in Binary codeDEZ = time missing to the end, in BCD code
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
S_SEVERZ = timer typeS = set inputTW = time constantR = reset inputT no. = timer numberQ = output timerDUAL = time missing to the end, in Binary codeDEZ = time missing to the end, in BCD code
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
S_AVERZ = timer typeS = set inputTW = time constantR = reset inputT no. = timer numberQ = output timerDUAL = time missing to the end, in Binary codeDEZ = time missing to the end, in BCD code
Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE
BIBLIOGRAPHY:Siemens Simatic Software Ladder Logic Programming manual