Delta Controls 2HTDCAL - Manual (Page 16)

{ACCESS 1}
15
{INPUT} [SELECT]
{PV UNITS}[SELECT]
Because the measured pressure is converted to a digital number the way the number
is displayed can be scaled to represent different engineering units, this affects the digital and
local display signals.
The prime variable (PV) units of measure are displayed, there are two choices :-
[SELECT] To abort and return to the {OUTPUT} menu.
[CHANGE] Used to change th e units of measure. There are set choices of units dependent
upon which output function is enabled.
LINEAR & SQUARE ROOT
{ InH20 }
{ InHG }
{ FtH20 }
{ mmH20 }
{ mmHG }
{ PSI }
{ Bar }
{ mBar
{ Gm/SQcm }
{ KG/SQcm }
{ PaScal }
{ KPaScal }
{Torr }
{ Atm }
Once the required units are displayed they can be selected and saved [[SELECT]]
or [SELECT] to abort to the {PV UNITS} menu.
Any change to the prime variable units will change all engineering units that are displayed,
upper and lower range limits, upper and lower range values and alarms.
The display may need to scroll to display the longer engineering units.
{ACCESS 1}
Pressing {CHANGE} will move down through the menu.
At the end of each sub-menu, select {ESCAPE} to return to the higher menu.
16
{INPUT} continued
{RANGEHI}[SELECT]
This is the pressure represented by 20 mA and may be less than range low to achieve reverse
action of the analogue output. This allows the analogue output of the transmitter to be re-ranged
without using a reference. It also sets a value to which { TRIM URV } will be set
under {ACCESS2}, below.
The URV is displayed followed by the engineering units there are two options :-
[SELECT] To abort displayed tag and return to {RANGEHI} menu.
[CHANGE] Used to edit the display.
The edit feature does not use a template because the values are entered in the current
engineering units. The screen is blank with a flashing {+} sign, work along the display entering
the value, use the character after {9} to depict a decimal point.
When the last character is reached [[SELECT]] will save the value and 20 mA will now represent
this new pressure on the analogue loop.
{RANGELO}[SELECT]
This is the pressure represented by 4 mA and may be greater than range high to achieve reverse
action of the analogue output. This allows the analogue output of the transmitter to be re-ranged
without using a reference. It also sets a value to which { TRIM LRV } will be set under
{ACCESS2}, below.
The display, options and edit features are the same as for RANGEHI.
This pressure will now be represented by 4 mA on the analogue loop.