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MAXIMUM/PERCENT HIGH SUBMENU:
Specify in percent, the maximum value (99) for control output. If the output is
analog proportional (Current or Voltage), then the maximum voltage or current, in
percent, is specified. 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, Pulse or Analog)
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 AçTN Action 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 Setpoint 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.
* If Analog Output (Current/Voltage) is your control Output 1, this menu i.e. CTRL
type will not appear, instead 4-20 Current will be displayed. Select ENBL for a
4-20 mA current (2-10 V Voltage) outputs or DSBLfor a 0-20 mA current (0-10 V
Voltage) outputs. If 4-20 mAis enabled, %HI/LO setting will have no effect.
Both Current and Voltage control outputs are active simultaneously.