Alpha Technologies Cordex Controller Ver.2.0 - Manual (Page 57)

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Scheduler Usage
The controller has basic scheduling capability that is implemented by using a System Time or
System Date signal in any customizable equation; used to trigger external events on a timely
basis, whether daily or at a specific date.
This is accomplished by using the System Time or System Date signal as an operator in a
Custom Alarm equation, which has been configured to change the state of a relay output. The
equation can include any other signals such as battery current or voltage for more advanced
control. The System Time or System Date signal can only be used with the following operators:
>, <, and =.
NOTE: the formats used for the Time and Date Operands are very specific and must
match exactly in order for an equation to be valid. For the System Time the
format is <hh.mm.ss>> and for System Date the format is <<20YY.MM.DD>>.
The '20' prefix for the year is what distinguishes the date from the time so it
must not be omitted when entering a Date Operand.
Example 1: The following equation in a Custom Alarm will cause the alarm to be true for ten
seconds (10s) at 2:35AM:
[System Time (HH.MM.SS)] > <<02.35.00>> & [System Time (HH.MM.SS)] < <<02.35.10>>
If the alarm is mapped to a relay, the relay will activate for 10s.
Example 2: Another example activates the alarm daily at 23:59:45 and clears when the battery
voltage is less than 46V. This is the equation for the alarm named Custom 2:
(([System Time (HH.MM.SS)] > <<23.59.45>>) | ([Custom 2] > 0)) & ([Battery Voltage] > 46)
Note the term: ([Custom 2] > 0). This is to latch the alarm ON since the term: ([System Time
(HH.MM.SS)] > <<23.59.45>>) will evaluate to false once the midnight rollover* (<<00.00.00>>)
happens.
*Midnight Rollover is described with an example under Custom Signals.
Example 3: We can use the previous example along with a Counter to set the alarm to activate
every three days. These are the equations for Counter 1:
Count Event "[System Time (HH.MM.SS)] > <<01.00.00>>"
Reset Event "[Counter 1]>2"
The will cause Counter 1 to count once daily at 01.00.00. When the count gets to three, it is
immediately reset back to zero. So, every third day, the count returns to zero.
Our Custom 2 alarm equation can now be:
(([System Time (HH.MM.SS)] > <<23.59.45>>) | ([Custom 2] > 0)) & ([Battery Voltage] > 46) &
([Counter 1] = 0)
The resulting behavior will be similar to that in Example 2, except the alarm will only activate
once every 3 days.