CSZ EZT-570S, Руководство пользователя

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EZT-570S User Manual
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Once the selection is made, press the “Return” button to go back to the analog input setup screen.
Enter the minimum and maximum values for the set point that the input is to provide to the loop and
press the “Save” button to save the changes. If you do not press the “Save” button, all changes will
be lost if you leave the screen or switch to a different analog input.
If you change the analog input type, change from voltage (Vdc) to current (mA) or vice versa,
power must be cycled to the EZT-570S controller in order for the input to switch types.
As the analog input signal is varied, it will provide a linear set point change from the minimum to
maximum value over the range of the input. Note that if the minimum or maximum set point
generated by the input exceeds the set point limits for the control loop, see Section 5.2, Setpoint
Limits, the EZT-570S will limit the set point to the minimum or maximum set point limits value as
defined in system setup.
Reversing Set Point Operation
For added flexibility with any type of set point sourcing device, the EZT-570S allows the set point
generated by the remote source to be inverted, meaning the minimum input signal, 0V or 4mA, will
set the maximum set point while the maximum input signal, 10V or 20mA, sets the minimum set point.
This is done by simply reversing the set point entries for the “Minimum” and “Maximum” fields.
For example, an input programmed to generate a set point between -40 and 100 for a 0-10V input
signal would be programmed with a “Minimum” of -40 and a “Maximum” of 100. By simply setting the
“Minimum” for 100 and the “Maximum” to -40, the set point generated by the 0-10V signal is reversed.
8.6.1.1 Enabling Remote Set Point Inputs
Once an analog input is configured for a particular loop, it must be enabled for use. By default, the
EZT-570S uses the set point entered manually from the loop view screen, or from an operating
ramp/soak program. The remote set points are enabled through events.
The event allows the user to manually select the use of the remote set point or control its use through
an automatic ramp/soak program. Each analog input has its own remote set point event. If the event
is on, the set point selected for the input is overwritten and controlled by the input signal. The EZT-
570S uses chamber events 11 through 15 for remote set point 1 through remote set point 5.