OPERATION
USERS GUIDE
5.2.4 ERROR DETECTION
.
~
The Instrumcnt and the mput
IS
checked for a rangc
of
fault~
.
>.
"
..
.-=---!
5.2.4.1 OPEN CIRCUIT
~
i
~
....
:
....
ThiS
IS
only chccked lor temperaturc scnsors. If
an
opcn
Clrclllt
I~
detected. thc
process variable
IS
forced
full
pOSill\e range or
full
negative range depending upun
- .
the
brnout
sellmg
III
the Inputs Illenu.
burn
will
be
shown on the display
111
place
or
the Process Variable display.
5.2.4.2 UNDER RANGEl OVER RANGE
TillS
IS
only checked
for
voltage or current Inputs. If the mput value
IS
tound to
be
greater thar .I
07%
of
full
range, or less than -I
07~0
of
full
range, It
IS
lJulIted to
107'}0
or
-107'70
of
full
range respec\ively.
In
tillS
case, either
OVEr
or
lI!\dEr
IS
shown
on
the display mstead
of
the process vanable valuc.
TIllS
condulOn will
al
so
occur If the user
nonlll1
condltlol1lng
IS
used and the
IIlput
t~lIs
belO\~
the
mlllllllUIll
entry or exceeds the
maXnllUI11
.
5.2.5 OUTPUT CONTROL
The alann Relays, LED alanns and current retransmission oplJons may
all
use the
filtered, condillOned Process Variable Value . This
IS
the same value which
IS
displayed.
TIllS
process responds to any errors detected . If the input
is
a temperature sensor,
an
open
CirCUit
will
lI1voke
the bumollt condition, gomg to
111
scale
or
low scale
dependmg upon the bumout programmll1g.
5.6 DISPLAY
TillS
will show the Process Vanable m engmeenng
lIllltS,
filtered and conditIOned. If
any errors have been detected, they
Will
be mdicated
on
the display. The number
of
places
of
decllnal
will
be
as delined
in
the
rES
entry
of
the Illputs menu,
but
if
there
are
more significant digits
than
can be displayed within the five digit field
available, the
number
will
be
right
justified
For example 1234.567 will
be
displayed as 1234.57 . Although the electrical input
IS
updated
ten
tllnes a second,
the display
IS
updated
at
the more visually practical rate
of
three tllnes a second.
SG4-2069-03
Page 67 INSTRUMENT OPERATION