Functions :
• Start to edit the parameter
• Enter into the sub-menu
• Confirmation of changes made in parameter being edited
Functions :
• Change of the present menu
• Modification of the parameter value
• Change of the display mode
ENTER
Symbol used in the manual : [ENTER]
Symbol used in the manual : [^] [v]
Loop Powered Display
250 SERIES
08
6. PRINCIPLE OF OPERATION
Power to the 250 Series display
is supplied from
current loop.
To ensure the display functions
correctly the signal of the current loop must be greater than 3.5mA.
If signal value is
below 3.5mA
a
running decimal point
is
displayed. Device configuration using remote controller is possible if signal
value of current loop is greater than 10mA (
Located on
front panel LED marked “
IR
”).
The measurement range equal to the nominal range is called: nominal measurement range,
and the measurement range equal to the extended nominal range is called: permissible
measurement range (figure 6.1).
If the result of measurement exceeds the permissible measurement range, warning “
-Hi-
” or “-
Lo-
” is
displayed rather than input signal, depends on exceeded value (see description of “
Lo r
” i “
Hi r
”
parameters, paragraph “
inPt
”
menu
).
”Lo r”
parameter
”Hi r”
parameter
Figure 6.1. Definitions of measurement ranges in mode 4 ÷ 20mA
If the measurement value do not exceed
the
permissible measurement range, but displayed value
exceeds range -999 ÷ 9999, the warning “
-Ov-
” is displayed rather than the calculated result.
6
.
1 MEASURING PRICIPLE