Battery Charging

NOMAD E2 Battery Charging Guide

Recommended Charging Settings for three stage charging

Stage 1.  Bulk.  Check the maximum current rate for your size E2 battery, this is listed on that models specification sheet, do not exceed that rate.

Stage 2. Absorption   The recommended voltage for absorption is between 2.4V – 2.44V per cell (14.4 – 14.6V for a 12V battery), 14.6V is Recommended.  Never ever exceed 2.45V per cell (14.70v for a 12v battery).

Stage 3.  Float.  Float voltage should be between 13.5V and 13.7V.  13.6V Recommended.

On Battery Chargers and Solar Chargers, choose the battery type selection that best matches these settings.


CARSPA 12/24V 20/40/60/80A MPPT Solar Charge Controller

Absorb Voltage. 14.6V for 12V System.  29.2V for 24V System.

MUSTPOWER PC1600 MPPT Solar Charge Controller Series

(20A, 30A, 40A , 45A, 60A)

PC1600 uses different terminalogy in the menu and manual.  Use the following x2 and x4 for 24v and 48v systems.

Menu  (what it means in other literature)  recommended setting

Setting 4, Absorb Voltage, 13.5V for 12V System

Setting 5, Refloat Voltage,  (Float Voltage), 13.7V for 12V System

Setting 6, Float Voltage.   (Absorb Voltage),  14.6V for 12V System

Setting 7, Max Charging Current.  This is listed on your size battery’s specification sheet (or as high as you can set it up to that figure)

Absorb Current.  Set this to the lower of the: max charge current of your battery and the maximum charge rate of the controller

NOTE: If you have batteries in parallel then multiply the current values by the number of batteries you have in parallel, as they are sharing the charging current

MUSTPOWER PV18 Solar Inverter Series

The default AGM setting on these inverters is too low.  Change battery type to user defined and adjust voltages to this

24v batteries set absorption stage voltage to 29.2V

48v batteries set absorption stage voltage to 58.4V

On PV18 HM series Inverters  this is settings 45 and 46

3kva  [46] 29.2V

5kva  [46] 58.4V

Float is ok as the default

3kva  [45] 27.4V

5kva  [45] 54.8V

On PV18 VHM series Inverters this is settings 14, 17 and 18

Change battery type in setting [14] to User Defined USE

3kw  [17] 29.2V

5kw  [17] 58.4V

3kw  [18] 27.4V

5kw  [18] 54.8V

MUSTPOWER Inverter Chargers

Choose setting    ‘AGM 2’

Other Chargers

In general choose the setting that says AGM, Sealed, Lead Acid in that order of preference.

State of Charge vs. Battery Voltage for Sealed Lead Acid Batteries

(not disturbed by charging or discharging effects and with surface charge removed)

Approximate state-of-charge


Open Circuit Voltage


Leave a Reply