Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE TIMERS When and how to use them.

Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE

TIMERSWhen and how to

use them


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)


Traffic light simulation system


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)


Radius lift arm


it is sometimes necessary to verify that a certain action is over within the given time or to stop it (time out alarm)


Automatic gate


TIMERS are tha macro instructions available in every PLC (programmable logic controller) in order to control the processes mentioned before.


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


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


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


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


BIBLIOGRAPHY:Siemens Simatic Software Ladder Logic Programming manual

Dott. Ing. Alessandro Paganin - I.T.I. Malignani UDINE TIMERS When and how to use them.

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