short coz-limit switch.ppt
Post on 13-Apr-2018
227 Views
Preview:
TRANSCRIPT
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 1/13
Discrete – LimitDiscrete – Limit
SwitchesSwitches
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 2/13
Application
Limit switches are used to detect:
absence or presence of objects
passing
positioning
end of travel (limit)
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 3/13
Symbol ( IEC ) and Composition
NO NC
S1
1
S1
1
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 4/13
A mechanical sensor
OPERATING PRINCIPLES
For detection, the object needs to
actuate the operator which in turnschange the contact from NO toclosed, or from NC to opened
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 5/13
OPERATING PRINCIPES
!FO"! #F$!"
!"#
$ac
!"#$ac
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 6/13
COMPOSITION
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 7/13
%&estion ' o to choose the ri*htsensor +
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 8/13
Positive Opening.
$he operation of a limit switch mustcompl% with standard &!C '*+*
-ection .: All the normally closed contact
elements of the switch can bechanged with certainty to the
o!en !osition "no fle#ible lin$between the mo%ing contacts andthe o!erator of the switch to whichan act&ating force is a!!lied'
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 9/13
The dis!lacements!eed of themo%ing contacts
is inde!endent tothe s!eed of theo!erator( S&itablefor low s!eed
act&ators
The dis!lacements!eed of themo%ing contacts
is e)&al or!ro!ortional tothe s!eed of theo!erator(
Snap Action Slo ,rea-
Characteristics
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 10/13
Operator & Detection Movement
Pl&nger Roller * Pl&nger
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 11/13
Operator & Detection Movement
lever
7/23/2019 short coz-limit switch.ppt
http://slidepdf.com/reader/full/short-coz-limit-switchppt 12/13
Operator & Detection Movement
/ultidirectional
top related