Apex Classic Setup and Programming Guide v2.2
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NOTE: The repeat interval is only used for legacy control bus devices like the
DC8, DC4HD, etc. AquaBus devices always have the correct outlet state once
communication is restored.
To modify the Repeat Interval (default is 5 minutes):
Apex Display: Setup – Outlet Setup – Repeat Interval –use the up/down
arrow keys to select the repeat interval, press OK to save or Exit to discard
changes.
Web Interface: This option is not available from the Web Interface.
NOTE: Do not set the Repeat Interval too frequent as the excess communication
on the Control bus (legacy devices) can interfere with normal operation especially
on larger systems.
PROGRAMMING WITH HYSTERESIS
Consider a heater outlet that is programmed to turn on the heater when below 80
degrees and turn it off at temperatures above 80 degrees. When the temperature
is hovering around the set point of 80 degrees, the heater could potentially come
on and off very rapidly as the temperature fluctuates between 79.9 and 80.1.
Also consider the float switch in the sump that controls an automatic top off
system. As the ripples in the water’s surface raise the float switch up and down
when the water level is right at the float’s set point, the switch can rapidly open
and close causing the automatic top off pump to rapidly turn on and off.
The AquaController provides several programming methods to avoid the
unnecessary stress on controlled equipment by programming with hysteresis.
SET POINTS
The simplest method to add hysteresis to your programming is to use set points
that avoid the possibility of rapid on/off outputs. Take the temperature example,
simply programming the heater to come on at temperatures over 80.0 and turn
off at temperatures below 79.7 will require that the aquarium temperature to
drop below 79.7 before turning the heater on. The heater will then have to raise
the temperature of the tank above 80 before the heater will turn off. The time it
takes to heat the aquarium .3 degrees will significantly reduce the number of
on/off cycles.
MINIMUM TIME
