
A solar panel's average tilt from horizontal is at an angle equal to the latitude of the site location. For optimum performance,
adjust the tilt by plus 15 degrees in the winter or minus 15 degrees in the summer. For a fixed panel with a consistent power
requirement throughout the year, adjust the tilt angle to optimize for the winter months: latitude plus 15 degrees. Although in
the summer months the angle may not be the most efficient, there are more hours of solar energy available.
For sites with snow in the winter months, the increased angle helps to shed snow. A solar panel covered in snow produces
little or no power.
9.4.3 Recommended Solar Configurations
These solar panel and battery combinations assume direct sunlight for at least two to three hours a day. Solar insolation
maps provide approximate sun energy for various locations. The depth of battery discharge is assumed to be 50 percent.
Table 58: Solar panel and battery combinations for a DXM system
Solar Panel
Output (W)
Battery Capacity (Ahr)
Days of
Autonomy
DXM Current
(mA)
DXM Model
5
10
10
25
DXM-Sx models with an ISM radio and I/O base board
20
14
10
30
DXM-Bx models with an ISM radio and no cellular modem
20
20
10
35
DXM-Bx models with an ISM radio and cellular modem
Battery capacity (amp hour) is a standard amp rating taken for 20 hours. Battery capacity should be monitored for reliable
system power and may need to be increased for cold weather locations.
9.4.4 Monitoring Solar Operation
The DXM solar controller provides Modbus registers that allow the user to monitor the state of the solar panel input voltage,
the battery voltage, the charging current, and the temperature in °C. The DXM can be configured to monitor the health of the
charging system as well as send an alert message when the battery is too low.
The charts show a typical charging cycle, with each vertical grid representing about eight hours. The chart shows three days
of charging.
Figure 55. Solar Panel Voltage (mV) -- Cloudy First Day
Figure 56. Battery Voltage (mV) - Cloudy First Day
9.5 Clear the Password for the DXM100 and DXM150 Models Only
By default, the DXM Controllers does not require a password to load a configuration file. If a password is defined, the
password must be entered before uploading a configuration file. To change the password, you must already know the current
password. If you do not know the current password, follow these steps to clear the password.
Sure Cross
®
DXM150 and 1500-Bx Wireless Controllers
www.bannerengineering.com - Tel: + 1 888 373 6767
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