User's Manual

Section 5877 User Instructions
Issue AQ, January 15, 2013 Spec. No. 582140000 (Models 802NLDB, 802NLEB and 802NL-B)
Page 3-14 Chapter 3. System Operating Procedures
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Method 3 (Automatic Test/Equalize) Procedure
In this method, a user enables the Automatic Equalize feature via the MCA Control
Panel. The system is automatically placed in the equalize mode and automatically
returns to float mode for the conditions as described above. Follow the procedures
described below.
Note: The automatic equalize feature is intended for use only with wet cell batteries.
Using this feature with valve regulated batteries is not recommended.
Description
This feature can be enabled or disabled by a user via the MCA. The default state is
disabled.
The Automatic Equalize feature is a time based function which is controlled by a
customer selectable multiplier and by the "System Battery is on Discharge" alarm
setpoint. The MCA’s default setting is for a multiplier of zero, which disables the
Automatic Equalize feature.
When the Automatic Equalize feature is enabled, if system voltage drops to less than the
"System Battery is on Discharge" alarm setpoint, the MCA initiates a timing cycle to
measure the discharge time period. The MCA requires at least 15 minutes of continuous
"System Battery is on Discharge" alarm in order to prevent nuisance equalization cycles.
When system voltage rises to above the "System Battery is on Discharge" alarm setpoint,
the MCA ends the discharge timing cycle and (assuming a minimum of 15 minutes has
elapsed) places the Rectifiers into the equalize mode for a customer selectable multiple
of the discharge time period (the discharge time period includes the initial 15 minutes).
The equalize time period can be set for 0 to 15 times the discharge time period, up to a
maximum of 300 hours. A zero (0) setting disables the feature.
When the Automatic Equalize feature is enabled, the MCA prevents a user from setting
the equalize value lower than the float setpoint. If the equalize value is set first, the MCA
automatically sets the Automatic Equalize Multiplier to zero (0), disabling the feature.
Manually setting the system to float or equalize mode cancels the automatic function, if
active.
Note: Equalization is only effective if the correct multiplier is entered to allow the battery
to charge to capacity. It makes no sense to end the equalize cycle before battery
capacity has been restored. To determine the multiplier, load current and system
capacity must be known. For example, consider a system with 200 amps of
Rectifier capacity and 150 amps of load. If there is a 2-hour outage of AC power,
300 amp-hours (150 x 2) will be drained from the battery. When AC power is
restored, the battery charge current will be 50 amps (200-150), and it will take at
least 6 hours (300/50) to replace the battery capacity. In this scenario, the
multiplier must be set greater than 3 for the Automatic Equalize feature to have
any effect.
Enabling and Disabling the Automatic Equalize Feature: To enable, set the "AUTO
EQUALIZE FOR ## x DISCHARGE" menu item in the MCA Configure Menu to a value
between 0 and 15. To disable, set the "AUTO EQUALIZE FOR ## x DISCHARGE" menu
item in the MCA Configure Menu to 0. A step-by-step procedure is provided next.
1) With SYSTEM OK being displayed on the MCA Interface Pad, press and release
the FUNCTION SET ENTER key. The FUNCTION MENU is displayed.
or
In the MAIN ALARM MENU, repeatedly press and release the FUNCTION
SELECT DOWN arrow key until "GO TO FUNCTION MENU" is displayed. Press