CHAPTER 4 APPLIED OPERATION
4-6
4.2 Alarm Hysteresis
•
/)*()!) % "(# %+*&+*) - $ "(#) ( )-!* $
)* ) %""%-)
Alarm value
UpperĆlimit
alarm
Alarm hysteresis
Alarm value
LowerĆlimit
alarm
Alarm hysteresis
ON
OFF
ON
OFF
•
"(# /)*()!) !) )* !$&$$*"/ %( "(# !$ * 0"(# /)2
*()!) *% &(#*() ,$ +$*!%$ )**!$ "," +"* !)
0
•
0*$/ )'+$ !) +$*!%$ - ! ""%-) * "(# %+*&+*) *%
*#&%((!"/ !)" - !" * !()* "(# %$!*!%$ %+() (%# (
%$ * "(# %+*&+* !) *!, %( +*+( "(# %$!*!%$)
•
%( .#&" !$ )*$( *!$ &&"!*!%$ ! /%+ +) * )*$(
0"%- "(# * "(# -%+" *!, (%# )-!* !$ * %$*(%""(
%-,( -!* 0*$/ '+$ * "(# %+*&+* !) !)"
+(!$ * !()* -(#+& $ * *#&(*+( ) *% (!) %, *
"(# )* &%!$* %( * "(# $ %# *!, $ ! * *#&(2
*+( "") "%- * "(# )* &%!$* * %+*&+* !) *!,
•
)*$/ )'+$ !) $" - $ $ "(# !) %+*&+* * !) %-2
,( ()*(* "*( / * 0)*$/ )'+$ &(#*( ,$
+$*!%$ )**!$ ","
%( *!") ) * 0)*$/ )'+$ &(#*( !$ 0 &*(
(#*()
•
0"(# "* !) +$*!%$ - ( "(# %+*&+* %$ *+($ )*/)
((")) % * *#&(*+(
•
"(# "* $ $" / *+($!$ * &%-( %* %-2
,( * * !* $ ")% $" / )-!* !$ *% * !$!*!" )**!$ ","
%##+$!*!%$) )**!$ "," ,$ +$*!%$ )**!$ "," %( "2
!(*!%$ ","
J
Standby
sequence
F
Restart
J
Alarm latch