45
e) Flow Alarm Power On Delay (Numerical entry)
Sometimes it is convenient to enable the Flow Alarm only after a specifi ed power-up
delay interval. The “Flow Alarm Power On Delay” option allows the user to set a
specifi ed time interval which must elapse from the moment of the device power-up
event before the Flow Alarm function will be activated. Valid settings are in the range
of 0 to 3600 seconds. The default value is 0: no delay.
f) Flow Alarm Action Latch (Tabular entry)
The Flow Alarm Action Latch settings control the Latch features. If SSR output is
assigned to the Flow Alarm event, in some cases the Flow Alarm Latch feature may
be desirable. The following settings are available: Enabled or Disabled. By default, the
Flow Alarm is nonlatching, which means that the Alarm action is indicated only while
the monitored Flow Rate value exceeds the specifi ed conditions that have been set.
g) Valve Close Action (Tabular entry)
In some applications it may be required to stop gas fl ow if actual fl ow is outside of
the target range. In this case “Valve Close Action” can be used. This menu selection
has 3 available options: Disabled, High Alarm, and Low Alarm. When assigned to
High or Low Alarm and corresponding Alarm conditions activated the instrument
control valve will be de-energized (Closed).
6.4.11 Submenu “Gas Pressure Alarm”
The DPC provides the user with a fl exible Alarm system that monitors the Fluid Pressure for
conditions that fall outside confi gurable limits and provides visual feedback for the user via
the OLED, status LED or an SSR output. The Pressure Alarm has several attributes which
may be confi gured by the user via the OLED/joystick interface or digital communication
interface. These attributes control the conditions that cause the Alarm to occur and specify
actions to be taken when the pressure reading is outside the specifi ed conditions.
Pressure Alarm conditions become true when the current pressure reading is equal to,
higher than or lower than the corresponding values of High and Low Pressure Alarm levels.
Alarm action can be assigned with a preset Delay Interval (0-3600 seconds) to activate
the SSR output. The Latch Mode control feature allows SSR output to be latched on or
follow the corresponding Alarm status.
The following settings are available for the Pressure Alarm (see Figure 19):
a) Pressure Alarm Mode (Tabular entry)
This function determines whether the Pressure Alarm is Enabled or Disabled, the two
selections available. The default entry is Disabled. Alarm Mode selections can be set
with the Joystick UP and DN buttons and are accepted by pressing the joystick
equivalent of an ENT button.
To Next Page
Loading...
