Alpha Technologies Cordex Controller Ver.2.0 - Manual (Page 14)

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3.7 Battery Auto Equalization
Auto Equalize (Auto-EQ) is a protective feature designed to ensure optimal lead acid battery life and performance.
With the CXC, auto equalize is used for two basic purposes: first, for providing a quick battery recharge after an
AC power failure, and second, as a long-term battery maintenance solution.
Refer to the battery manufacturer’s recommendations for equalization charging.
3.7.1 Battery Charge Auto Equalize
Battery Charge Auto Equalize can be used after a prolonged AC power failure, when the battery voltage has
decreased to a low level.
Once the batteries have decreased beyond the auto equalize low voltage threshold, the CXC will enter an armed
mode. When AC power returns, the system voltage begins to increase, which charges the batteries.
Once the system voltage increases to the high voltage threshold, the CXC enters the equalize mode and begins
to equalize charge the batteries for a period specified by the Supervisor in the AUTO-EQ DURATION submenu.
This is done to ensure the EQ duration is not effectively reduced by the time it takes to recharge the battery back
to the nominal system voltage.
3.7.2 Periodic Auto Equalize
Periodic Auto Equalize can be used for maintaining the long-term integrity of a battery string. Over time, individual
battery cell voltages may vary greatly. As a result, to ensure that batteries remain in optimum condition, they
should be equalize charged at regular intervals. The CXC enables the Supervisor to program the time between
automatic equalize charging of the battery string in the AUTO-EQ INTERVAL submenu.
3.7.3 Battery Current Termination (BCT) Equalize
The BCT Equalize feature provides an alternative method of ending EQ mode early to prevent over-charging of
the battery. Once enabled, it will only be active when EQ mode is caused by a Charge Auto Equalize.
BCT EQ will terminate Charge Auto EQ when the battery current falls below the BC Threshold setting. Upon initial
activation of EQ mode – that is triggered by the Charge Auto EQ feature – the CXC will wait for one minute of
system stabilization time before monitoring the battery current for BCT EQ. After one minute, the battery current is
checked about once per second to see if the current has fallen below the BC Threshold.
When the battery current falls below the BC Threshold, and remains below the threshold for three seconds, the
EQ duration is replaced with the BCT duration. After this time, the system returns to FL mode.
3.8 Battery Monitor and Charge Current Control
The Battery Monitor feature enhances the CXC’s capability to provide information about the battery to the User.
Charge Current Control will help increase battery longevity by keeping the battery current to within specified limits.
Charge current to the battery during recharge will be limited to a value as programmed by the Supervisor. This
value will be derived from the battery manufacturer’s specification sheet and entered by the Supervisor.
A battery run time prediction will be performed while the battery is supplying power to the load. The CXC will
collect data to estimate the time it will take the battery to be drained. If the Battery Monitor feature is enabled and
the battery is sourcing current to the load, a time estimate appears in the Mode Status screen. Runtime estimate
is also available in the Analog Signals display, which can be enabled for display status in (SIGNALS)
CONFIGURE SIGNALS\CONTROLLER SIGNALS.
During an AC outage or Battery Test, data will be collected to calculate a capacity prediction. A capacity of 80%
means the battery is due to be replaced. The accuracy of this will improve as the battery undergoes more
discharge cycles.