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MAXIMUM/PERCENT HIGH SUBMENU:
Specify in percent, the maximum value (99) for control output. If the output is
time proportional (Relay, SSR, or Pulse), then the maximum duty-cycle, in
percent, is specified.
Press d12) Display flashes 1st digit of previous “Percent High” setting.
Press b& c13) Use band cbuttons to enter a new value for “Percent High”.
Press d14) Display shows STRD stored message momentarily and then
advances to CTRL Control Type Submenu.
Example: On an Analog Output of 0~10 Vdc, a setting of %LO = 10 and %HI = 90,
cause the minimum on the control output to be 1 V and the maximum on the
control output to be 9 V. The same setting on a time proportional output, will
cause 10% duty cycle for the minimum control output and 90% duty cycle for
maximum control output. To disable %LO/HI, set LO to 00 and HI to 99. If
%LO/HI
is at other values than the default (%LO = 00, %HI =99), SOAK is disabled.
*CONTROL TYPE OUTPUT: (Relay, SSR, or Pulse)
Press d15) Display flashes ON.OF On/Off or PID Proportional, Integral,
Derivative.
Press b16) Scroll through the available selections: “ON/OFF” or “PID”.
Press d17) Display flashes STRD stored message momentarily and
then advances to AçTN only, if it was changed, otherwise press
ato advance to AçTNAction Type Submenu.
The ON/OFF control is a coarse way of controlling the process. The “Dead
Band” improves the cycling associated with the On/Off control. The PID control is
best for processes where the set point is continuously changing and/or a tight
control of the process variable is required. PID control requires tuning and
adjustment of the "Proportional", "Integral or Reset" and "Derivative or Rate"
terms by a trial-and-error method. The instrument provides an "Auto Tuning"
feature making the tuning process automatic, possibly optimum.
ACTION TYPE SUBMENU:
The error that results from the measurement of the Process Variable may be
positive or negative since it may be greater or smaller than the Setpoint. If a
positive error should cause the instrument output to increase (i.e. cooling), it would
be called Direct Acting. If a negative error should cause the output to increase
(i.e. heating), it would be called Reverse Acting.
Press d18) Display flashes DRçT Direct or RVRS Reverse.
Press b19) Scroll through the available selections: “Direct” or “Reverse”.
Press d20) Display shows STRD stored message momentarily and then
advances to AUTo only, if it was changed, otherwise press ato
advance to AUToAuto PID Submenu (if PID Control Type was
selected).