P.but
(
P
button function)
The
P
button may be set to operate some of the remote input functions, see
R.INP
below for a
description of these functions. If both the remote input and
P
button function are operated simultaneously
the
P
button will override the remote input. The functions below are as described in the
R.INP
function
above with the exception of the
P.SEt
function.
Functions available are:
NONE
,
Hi
,
Lo
,
HiLo
,
tARE
or
ZERO
Note: To prevent accidental operation of the
P
button in the
tArE
or
ZERO
functions it is necessary
to hold the button in for 2 seconds to perform the selected operation.
R.INP
(remote input function)
See the “Electrical Installation” chapter for the location of the remote input electrical connector.
When these pins are short circuited, via a pushbutton or keyswitch the instrument will perform the selected
remote input function. A message will flash to indicate which function has been selected when the remote
input pins are short circuited. The remote input functions are as follows:
NONE
- no remote function required.
P.HLd
- peak hold. The display will show the peak value only whilst the remote input pins are short
circuited.
d.HLd
- display hold. The display value will be held whilst the remote input pins are short circuited.
Hi
- peak memory. The peak value stored in memory will be displayed if the remote input pins are short
circuited, if the short circuit is momentary then the display will return to normal measurement after 20
seconds. If the short circuit is held for 1 to 2 seconds or the power is removed from the instrument then
the memory will be reset.
Lo
- valley memory. The minimum value stored in memory will be displayed. Otherwise operates in the
same manner as the
Hi
function.
HiLo
- toggle between
Hi
and
Lo
displays. This function allows the remote input to be used to toggle
between peak and valley memory displays. The first operation of the remote input will cause the peak
memory value to be displayed, the next operation will give a valley memory display.
P Hi
or
P Lo
will
flash before each display to give an indication of display type.
tARE
- display tare. Short circuiting the remote input pins momentarily will allow toggling between nett
and gross values (shown as
NEtt
and
gROS
). If the remote input is short circuited for approx. 2
seconds the display will be tared and will show zero. The tare will be lost if power is removed.
ZERO
- display zero. Zeroes the display in same manner as the tare function except that the zero is not
lost when power is removed and the display will zero as soon as the remote input is short circuited.
SP.AC
- setpoint access only. This blocks access to any functions except the alarm setpoint functions
unless the remote input pins are short circuited or entry is made via
CAL
mode.
No.AC
- no access. This blocks access to all functions unless the remote input pins are short circuited
or entry is made via
CAL
mode.
CAL.S
- calibration select. The remote input can be used to select between calibration scaling values.
Two different sets of calibration values, decimal points and display units can be entered in the LD4, one
set with the remote input open circuit and another set with the remote input short circuit to ground. The
remote input can then be used to switch between one set and the other. This feature can be used on all
input ranges. For example: With the remote input open circuit a 4-20mA input can be scaled (using
CAL1
&
CAL2
or
USER En4
and
USER En20
) to read
0
to
100
over the 4-20mA range. With the
remote input short circuit to ground the scaling can be repeated using figures of
0
to
50)0
for the
4-20mA range. The remote input can be used to switch between ranges. In this example the first
scaling could represent a % figure and the second scaling could represent the actual process units
(litres, kg, volts etc).
duLL
- display brightness control. The remote input can be used to change the display brightness.
When this mode is selected the display brightness can be switched, via the remote input, between the
brightness level set at the
brgt
function and the brightness level set at the
duLL
function.
Page 18 of 46
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