Vertiv 581126000, User Manual

Page: 46 / 208

Vertiv
| +24 VDC Power System User Manual (Section 6013) | Rev. G
46
Low Voltage Disconnect NOR/INH Switch and INH Indicator (if low voltage disconnect load contactor is
furnished)
Located inside each Distribution Cabinet. Refer to
Figure 1
.
CAUTION! Before returning the NOR/INH switch from the INH position to the NOR position, check the
MCA for the presence of low voltage disconnect alarms. If alarms are active, use the MCA to reconnect
the low voltage disconnect circuits.
DO NOT return the NOR/INH switch to the NOR position until you verify that there are NO low voltage
disconnect alarms active. If the switch is returned to the NOR position when low voltage disconnect
alarms are active, battery and system output will disconnect from the controlled load(s).
WARNING! While the NOR/INH locking toggle switch is in the INH position, the battery and system
output will not disconnect from the controlled load(s) if battery voltage decreases below the low voltage
disconnect setpoint. For maximum battery protection, this switch should NOT be left in the INH
position.
Refer to Table 2 .
Table 2:
Load Low Voltage Disconnect Control and Indicator
Control / Indicator Description
NOR/INH
(Normal/Inhibit Switch)
•
NOR
(Normal Switch
Position)
•
INH
(Inhibit Switch
Position)
This is a locking type toggle switch. To operate switch, pull out switch handle
and move handle left or right to desired position. Release handle to lock into
new position.
•
For normal low voltage disconnect operation, place this switch in the
NOR position.
•
The low voltage disconnect circuit is disabled and the battery and
system output remain connected to the controlled load(s) when this
switch is in the INH position. This allows testing, adjusting, or removal of
the low voltage disconnect circuit card(s) without disconnection of the
load(s).
Note:
Placing this switch in the INH position inhibits the LVD function only in
cabinet containing this switch. Other cabinets containing LVD
contactors or controlling external LVD contactors will continue to
operate with normal LVD function.
Low Voltage Disconnect
INH (Inhibit) Indicator
Illuminates when the low voltage disconnect circuit has been disabled through
the use of the NOR/INH switch as described above.