Display Mode
The DISP in the set up menu is used to select the dis-
play format under normal conditions. If PV is selected,
the display will indicate the process value. If SP1 is
selected, the display will indicate HSP1 value for high
limit control (OUT1 = HI) and high/low limit control
(OUT = HI.LO) or indicate LSP1 value for low limit con-
trol (OUT1 - LO). If SAFE is selected, the display will
indicate the word SAFE for he normal condition.
However, the display will indicate the process value if
the process value goes beyond high limit or low limit. If
an error condition occurs, the display will indicate the
error symbol.
Normal Display
During normal operation, the unit can be configured to
display the process value, high limit or low limit set
point (HSP1 or LSP1 dependent on OUT1 selection) or
the word SAFE.
Abnormal Display
Whenever the process is outside the normal range, the
process value will be displayed.
15
Reference Data
The are three different types of reference data con-
tained in the set up menu. The reference data is read-
only data. The maximum historical PV, displayed
by
, which shows the maximum process value
since the last UNLOCK operation. The minimum histori-
cal PV, displayed by
, which shows the minimum
process value since the last UNLOCK operation. The
abnormal time, displayed by
, which shows the
total accumulated time (in minutes) that a process has
been in an abnormal condition since the last UNLOCK
operation.
The reference data values will be initiated as soon as
the RESET key is pressed for 4 seconds (UNLOCK
operation). After the UNLOCK operation, the PV.HI and
PV.LO values will start from the current process value
and the T.ABN value will start from zero.
Process Input
INPT:
Selects the sensor type and signal type for
the process input.
UNIT:
Selects the process unit.
RESO: Selects the location of the decimal point
(Resolution) for most (not all) process related
parameters.
IN.LO: Selects the low scale value for the linear type
input
Hidden If: T/C or RTD type is selected for
INPT.
IN.HI:
Selects the high scale value for the linear
type input.
Hidden If: T/C or RTD type is selected.
How to use IN.LO and IN.HI:
If 4-20mA is selected for INPT, let SL specify the
input signal low (i.e., 20mA), S specifies the current
input signal value, the conversion curve of the
process value is shown as follows:
Process Value
Figure 5.2
Conversion Curve for
Linear Type Process
Value
Formula: PV = IN.LO + (IN.HI - IN.LO)
EXAMPLE: A4-20mA current loop pressure transducer
with range 0 - 15kg/c
2
m is connected to input, then per-
form the following set up:
INPT + 4-20MA
IN.LO = 0.0
UNIT = PU
IN.LO = 15.0
RESO - 1-DP
Of course, you may select another value for RESO to
alter the resolution.
S-SL
SH-SL
