Tempco TEC-2500, Instruction Manual

Page: 61 / 108

57
3–24 Display Mode
Operation
Press several times until (display) appears on the display. Then press to enter
display mode. You can select more parameters to view by pressing or pressing in
reverse sequence. The system mode of the controller and its operation will remain unchanged.
When the controller enters display mode the display will alternate between showing the display
parameter and the parameter value.
PVHI/PVLO show the historical extreme (maximum or minimum) values of the process on the
upper display. The historical extreme values are saved in a nonvolatile memory even when it is
unpowered. Press for at least 6 seconds to reset both the historical values PVHI and PVLO
and begin to record new peak process values.
shows the percentage control value for output 1, while shows the percentage
control value for output 2.
DV shows the difference value between process and set point (i.e., PV-SV). This value is used
to control output 1 and output 2.
PV1 shows the process value of input 1.
PV2 shows the process value of input 2.
PB shows the current proportional band value used for control.
TI shows the current integral time used for control.
TD shows the current derivative time used for control. Since the controller is performing
FUZZY control, the values of PB, TI, and TD may change from time to time.
CJCT shows the temperature at the cold junction, measured in °C independent of the unit
used.
PVR Shows the changing rate of the process in °C (or °F or PU) per minute. It may be
negative if the process is going down.
PVRH/PVRL The maximum and minimum changing rate of the process since power up, as
measured in °C (or °F or PU) per minute. PVRH is a positive value while PVRL is a negative
value.
NOTE
The controller will never revert to its PV/SV display from display mode
unless you press the keys.
PVHI
PVLO
MV1
MV2
DV
PV1
PV2
PB
TI
TD
CJCT
PVR
PVRH
PVRL