Owner`s manual

VANNER Incorporated Testing and Troubleshooting
70-Series Power Management System OWNER’S MANUAL
12
Caution adding 12volt batteries
In certain applications, such as private coach or alternate energy applications, it may be desirable to have
additional 12 volt “House Batteries” to operate heavy 12 volt (inverter) loads. Use the VANN-Guard to
charge the additional batteries.
Connect the VANN-Guard 12V terminal to the additional batteries only. Do not connect the VANN-Guard
12V terminal to both battery banks as this would make Battery A larger than Battery B. Damage to
Battery B may occur during charging due to overcharging, if the VANN-Guard cannot keep up with the
charging system.
Caution using a Ground-Side Battery Disconnect Switch
The system must be wired as shown to prevent Reverse Polarity Damage to polarity sensitive12 volt
loads while the ground-side disconnect switch is open. The VANN-Guards GND terminal must be wired to
the battery side of the ground-side disconnect switch circuit for the VANN-Guard to work properly.
Install the external High Current Diode, such as Vanner Model 52-75 (45 amp continuous rating) to
protect polarity sensitive 12 volt loads if these loads do not already contain input diode protection. This
prevents a reverse polarity on the 12 volt equipment when the battery switch is open. The reverse polarity
does not come from the VANN-Guard, but from any 24 volt equipment that may be turned ON.
+
12 V
Battery A
-
+12 Volt
Loads
(Radio)
+24 Volt
Loads
+
12 V
Battery B
-
+
24V
Alt
-
VANN-Guard
+24V
GND
+12V
F1
F2
+12V
+24V
High Current Diode
Battery Disconnect Switch
+
12 V
Battery A
-
+
12 V
Battery B
-
+
24V
Alt
-
VANN-Guard
+24V
GND
+12V
F1
F2
+24V
+
12 V
Battery C
-
+
12 V
Battery C
-
+
12 V
Battery C
-
+12V
+
12 V
Battery A
-
+
12 V
Battery B
-
+
24V
Alt
-
VANN-Guard
+24V
GND
+12V
F1
F2
+24V
+
12 V
Battery A
-
+
12 V
Battery A
-
+
12 V
Battery A
-
+12V
F1
Acceptable
Battery A and Battery B Are
The Same Size
Unacceptable
Battery A and Battery B Are
NOT The Same Size