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SEE SETUP ON HOW TO SELECT ONE OF THE DISPLAY MODES.
RETAINING USER SETTINGS ON POWER DOWN
DPS3301 saves all the programmed parameters in an EEPROM (electrically erasable programmable read
only memory). An EEPROM stores the programmed parameters even when the power is removed from the
unit. However, it is important to note that if the parameters are being changed during setup, they must be
saved in the EEPROM by
pressing and holding the ‘RESET’ key (till SAVING is displayed) as described
under SETUP. If parameters are
NOT saved and the power is removed from the unit, any newly changed
values will be lost ( the unit will, however, maintain the old values).
DISPLAY UNITS C/F:
DPS3301 units can display temperature in either degrees
Centigrade of Fahrenheit. To switch the display from Fahrenheit
to Centigrade or vice versa, simply push the C/F key once. The
display will read ‘dEGrE F’ if the unit enters degrees Fahrenheit
mode. It will display ‘dEGrE C’ if Centigrade mode is enabled.
Following the message, the unit will start displaying temperature
in selected engineering units.
SETPOINT DEVIATION:
A useful feature of DPS3301 units is tracking of a setpoint
relative to process value at any given point in time. To display
deviation, push the key labeled ‘SP DEV’ once. The display will
read ‘SP DEVN’ following which the deviation reading will be
shown. A second push on the same key while it is displaying
deviation will indicate the current setpoint value.
Setpoint value that needs to be tracked can be entered in two
different ways. One is during setup mode and the other is using
the front key labled ‘SP DEV’. SETUP mode entry is used when
a particular value needs to be programmed e.g. 500, 850 and so
on. To enter Setpoint in this mode, look under ‘SETUP’.
If it is desired to start tracking setpoint deviation from
current process reading then front key entry mode is
used. Assume that current reading on the display is 476 F. To enter this temperature as your setpoint, first
push ‘SP DEV’ key twice (first push displays deviation from current setpoint, and the second push displays
current SETPT value). After the second push keep
holding in the ‘SP DEV’ key. After a brief delay the
display will flash the message ‘SETPT’ three times. Following the third flash, the unit will take the current
process reading and save it as the new SETPOINT. If the process reading is 500, then taking our above
example, pushing ‘SP DEVN’ key will display 24 as your deviation value. Note that if ‘SP DEVN’ key is
released before three flashes of ‘SETPT’ message, the unit will not enter a new setpoint. However, old
setpoint value will be retained in the memory.
DISPLAY HOLD FEATURE:
DPS3301 offers a display hold feature. When ever pins 13 and 14 are shorted together (e.g. through a remote
switch), the reading taken at the time of shorting is frozen on the display. The unit will continue displaying
this value until the short is removed. This is indicated by the display periodically flashing the message ‘Pr
HoLD’. Internally the unit keeps monitoring the actual process and limits and timers will be activated if
process exceeds their programmed values. However, the display will indicate the hold temperature.