Xantrex ALM - REV A, Manual

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©2001 Xantrex Technology Inc.
P/N 975-0027-01-01 Rev A 09/01
3.0 OPERATION
When using this type of configuration, the separate diversion or “dump” load
must be able to absorb more power than the charging source is able to produce at
its peak output; otherwise, the DC voltage becomes unregulated. The current draw
of the diversion load is very important. Problems can arise from operating with a
load that is too small or too large. A diversion load that is too small will not be able
to absorb all the excess power from the current source once the batteries are full; a
load that is too big may cause a large in-rush of current above the design rating of
the relay, causing premature failure. A good design practice is to use a diversion
load that draws about 25% more current than the charging source’s maximum
output capability. The diversion load must be available for the diversion of power at
all times. Resistive-type heating elements are the best diversion loads. Special
direct current water heating elements are available. Light bulbs and motors are not
recommended.
BATTERY VOLTAGE IS WITHIN
ACCEPTABLE LIMITS
BATTERY VOLTAGE EXCEEDS
ACCEPTABLE LIMITS
N.O.
N.C.
COM
ALM
120 VAC
Coil
N.O.
COM
N.O.
N.C.
COM
ALM
External Power Relay
120 VAC
Coil
BATTERY BANK
+ -
External Power Relay
N.C.
N.O.
COM
N.C.
Communications
Cable
J1
Inverter
AUX
J1
Inverter
AUX
Communications
Cable
BATTERY BANK
+ -
DIVERSION
LOAD
DIVERSION
LOAD
Figure 3-7
Using the ALM as a Diversion Load Controller
Low-Voltage Alarm
The ALM can be configured to monitor the inverter’s battery voltage and to
engage an external alarm when the battery voltage decreases to a low level.
N.O.
N.C.
COM
EXTERNAL
INDICATOR POWER
SOURCE
INVERTER'S BATTERY VOLTAGE IS WITHIN
ACCEPTABLE LIMITS
External
Error
Indicator
External
Alarm OFF
Switch
INVERTER'S BATTERY VOLTAGE IS BELOW
ACCEPTABLE LIMITS
N.O.
N.C.
COM
External Error
Indicator
External
Alarm OFF
Switch
EXTERNAL
INDICATOR POWER
SOURCE
ALM ALM
Inverter
AUX
Communications
Cable
J1
Inverter
AUX
Communications
Cable
J1
Figure 3-8
Low-Voltage Alarm Configuration