CAL.S - calibration select. The remote input can be used to select between calibration scaling
values. Two sets of calibration values can be entered in the display, one set with the remote
input terminals open circuit and another set with the remote input terminals short circuit to
ground. The remote input can then be used to switch between one set and the other. For
example: With the remote input open circuit a 4–20mA input can be scaled (using CAL1
and CAL2 or USER En4 and USER En4) 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 500 for the 4–20mA range. The remote input can be used to switch between ranges.
In this example the first scaling could represent a percentage figure and the second scaling
could represent the actual process units (litres, kg, volts etc). Note: Alarm settings will not
change when changing between calibrations scales. i.e. Only one set of alarm functions can
be made and the alarm relay will operate from those set values no matter which calibration
scale is being viewed at the time. The dISP unit, dCPt and ZERO RNGE functions
can be individually set for each channel. If P.SEt is used only one preset value can be used
but only the channel displayed at the time is affected. Note; using different dCPt settings
between channels will affect the preset and alarm setpoint values e.g. a preset of 25 on a
channel with dCPt = 0 will become 2.5 on a channel with dCPt = 0.1.
P.SEt - preset value. The remote input can be used to force the display to the preset value, this
preset value is set at the P.SEt function.
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
terminals, between the brightness level set at the brGt function and the brightness level set
at the duLL function.
d.SCL - applicable only if the dummy load option board is fitted. When the dummy load option
board is fitted this option allows the input to be switched from the load to the dummy load.
When the dummy load is activated the display will show the scaling value for the dummy load.
The scaling value should be noted once installation is complete. Note that if the display is re
calibrated or zeroed then the scaling value for the dummy load will change and a note of the
new value should be taken. The tare operation will not alter the dummy load scaling value.
An adjustment screw allows some adjustment of the value displayed. Whilst the dummy load
is connected the display will flash the message d.SCL approximately once every 8 seconds.
If the dummy load is activated via a momentary action switch (or via the front P button)
the display will revert back to a normal live input display value after 20 seconds. If a latching
switch is used to activate the dummy load then the display will show the dummy load value
and flash the d.SCL message until 20 seconds after the remote input is released. For 5 digit
displays the activation of the dummy load will also cause the “A2” annunciator LED to light
during the duration of the dummy load display. The value shown for the dummy load does
not affect normal relay or retransmission operations.
O.Put- serial “print” output - applicable only when the serial output option is fitted - allows the
remote input to be used to initiate a single serial string output. The value output can be set
to the live input value, the display value or one of the appropriate remote input functions.
If a remote input function is selected such as HiLo then in addition to the serial output
function (SERL) being selected as HiLo a remote input (R.INP) or the P button (Pbut)
function must also be set to HiLo. The serial output will be a single string beginning with
a start of text character <STX> and ending with a carriage return <CR> the value will
occur between these two control characters. In the case of a HiLo operation the high value
will be separated from the low value by a comma. e.g.:
<STX>Hi value, Lo value<CR>.
PM4IVMAN-2.4-0 31 of 56
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