Delta Controls 2HTDCAL User Manual
Page 7
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{ACCESS 2}
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The FIXLOOP and trim functions are used to remove any differences between calibration
and site current standards. The electronics generates and monitors the output current
continuously but variations in site standards may require the output gain and zero to be
trimmed. The FIXLOOP command may also be used to calibrate other instruments and
controllers within the loop, by controlling the current within the loop .
{FIXLOOP}[SELECT]
This command will fix the loop at any current from 3.8 mA to 22 mA.
Set the value to 0.00 to release control of the loop.
When change is pressed the first character starts to flash, change cycles the numerals
while select moves to the next character. When the last numeral is reached the whole
display flashes and you have two choices.
[SELECT]
Aborts the edit and returns to {FIXLOOP}
[[SELECT]]
Performs the [SAVE] function and sets the loop current.
L
CAUTION
Make sure that the loop is isolated or safe !!
LOCAL CONFIGURATOR INSTALLATION & WIRING
L
CAUTION Make sure that the loop is isolated or safe !!
The local configurator / display is connected to the transmitter with a length of ribbon cable which
carries power, display drive and switch signals to the microprocessor. The cable is terminated in
an IDC connector that fits into the header on the top connection board, the plug is keyed to ensure
correct polarisation. PLEASE NOTE the transmitter should have its loop wiring fitted before the
display is connected which will ensure the display cable is not damaged.
When the display is connected the assembly can be pushed into place, check that the 'O' ring is
serviceable and apply light silicon grease if necessary. Engage the display and with firm pressure
on the outside edge push the unit home until the display face is level with the top of the housing.
DO NOT apply pressure to the clear window as you may damage the display.
Once the display unit is fitted the zero and span buttons on the top board are disabled, access to
the zero and span options being made through the menu system :-
{ACCESS 2}, {INPUT},{ZERO KEY} or {SPAN KEY}
(see Section on ACCESS2 for details)
When necessary the unit may be removed by using the handle provided, with firm pressure and
your thumb on the edge of the housing.
DO NOT ROTATE THE DISPLAY IN-SITU
If the display needs to be rotated for ease of viewing the display unit should be removed and then
re-seated in its new position.
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