Ametek MP3 SCR DeviceNet Head, Руководство HDR HMI

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out equal to <Auto RegMode NV>. It also shows the value of <Local RegMode>,
which may be modified at the bottom of the screen to apply a different regulation
mode only when using a local digital setpoint.
The top right corner of the screen supports two items. The left item will display the
current SCR firing mode in use: PF (phase firing), ZF (proportional zero firing),
or ZFT (zero firing into a transformer). The item to the right of Firing Mode is
usually a default Ametek HDR logo.
This HMI version includes a demo PLC like program that can automatically switch
between PF and ZFT mode based on load resistance. When this feature is
enabled, the message shown will be displayed.
3.4.4 Home Screen: Setpoint, Stop/Run, and Manual Controls.
In many applications, a manual command setpoint control is required. Traditionally,
this was built using a two position rotary switch and a 10-turn locking potentiometer.
This allowed a preset command to be set with a switch to select either automatic
control, or manual control using the front panel potentiometer setting. This HMI
replaces this hardware.
There are four important items in this view of the Setpoint rotary switch.
First, a touch controlled Auto/Manual Setpoint rotary switch is available to
switch the control from automatic to manual setpoint. The default automatic
command setpoint comes from an analog input on the front of the controller
(typically 4-20mA). Alternatively, DeviceNet may provide the command
setpoint. Either method is considered automatic from the view of the front panel.
When this switch is in the Auto position, two information boxes appear above it.
One displays the current setpoint controlling the unit. The box below it displays
either Auto Setpoint From Analog, or Auto Setpoint From Network (DeviceNet)
to indicate the source of the setpoint value.
Manual Setpoint control is selected by touching the rotary switch to toggle it to the
Man (manual) position. When in the manual position, the space above the switch
changes. It will now show the manual setpoint and UP/DOWN buttons to change the
setpoint from 0 to 100%. The “H” on the arrow buttons is a reminder that if the key
is held longer than two seconds, the value auto-increments or decrements depending
on the arrow direction.
NV – This reflects the value of the configuration parameter <Local Setpt NV>. The
NV in the lower left corner of the switch indicates that the Setpoint control is
configured to be non-volatile. This means that if all power is removed and restored,
the MP3+HMI will remember the last position of the setpoint rotary switch. The last
manual setpoint value will also be remembered and restored. This non-volatile setting