25
Water. Quality. Secured
.
9.3
Monitoring HydroGuard Alarms
HydroGuard issues alarms when it detects chemical levels that are above or below
the allowed range. Every alarm is automatically displayed in the LCD status display
and logged in the data logger. Most deviations in chemical levels, however, are
automatically corrected. Thus, the internal alarms do not immediately activate an
external alarm. A delay mechanism prevents false alarms from minor deviations that
were automatically corrected. The external alarm is only activated after an internal
alarm has been continuously active for a certain period of time, as defined by the
operator. The Alarm Delay command in the Operator menu sets the number of
seconds HydroGuard waits before closing Relay 5, the relay that operates the
external alarm. Only one alarm is shown at a time based on importance and the
order in which it should be fixed. For example, if the pH is high and the ORP is low,
only the pH alarm will be indicated since lowering the pH will likely also correct the
low ORP. All of the alarms are presented in the following Table: