UM581127000 User Instructions
Issue AB, March 22, 2012 Spec. No. 581127000 (Model 710NPBA)
Page 6 Chapter 2. Operating Procedures
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Optional LVD Driver Circuit Card
The optional LVD driver circuit card contains an LVD inhibit switch and indicator. Refer to
Figure 2-3. This card is required for 2-, 3-, or 4-row distribution cabinets that contain
three or more LVD contactors (LVBD and/or LVLD); or if the distribution cabinet is
equipped with an LVBD contactor rated 1200A or higher.
Caution: If the switch is returned to the ON (normal) position when low voltage
disconnect alarms are active, a low voltage disconnection will occur.
Warning: While the LVD inhibit switch is in the OFF (inhibit) position, a low
voltage disconnection will not occur if battery or load voltage decreases
below the low voltage disconnect setpoint. For maximum battery
protection, this switch should NOT be left in the OFF (inhibit) position.
Figure 2-3
Optional LVD Driver Circuit Card (P/N 540972)
LVD Inhibit Switch
Momentary UP / Middle / Down
Momentary UP Position: Closes all LVD Contactors (inhibit mode).
Middle Position: OFF (ACU+ DOES NOT control LVD’s) (inhibit mode).
DOWN Position: ON (ACU+ controls LVD’s).
LVD Inhibit
Active Indicator
Illuminates when the
low voltage disconnect
circuit has been disabled
through the use of the
LVD Inhibit switch.
J6 J5 J4
J3 J2 J1
J9
J7
S1
Note: The UP position will not close the LVBD contactor
if the battery is manually disconnected using the
Manual Battery Disconnect Switch.
