Many people believe that MPPT type chargers are always better than PWM chargers:
We have compared at
least one commonly used MPPT charger with the SC-2030 and found that under very ordinary conditions the SC-
2030 delivered
more
charge to the batteries. We measured this when the ambient temperature was 70 F degrees in
full sun, and when the proper panels matched to the batteries were being used and when charging over 13.0 volts
(the most common charging range with lead acid batteries.)
The SC-2030 is a "PWM" (Pulse width modulated) type that is simpler and less costly
than a "MPPT"
(Maximum Power Point Tracking) type charger. As said, the SC-2030 can give even better performance under some
common situations. MPPT technology can give some advantage when temperatures are low, and it is
necessary
for
good power transfer when panel voltage is much higher than the battery system voltage. With the SC-2030 (or other
PWM charger), you may be able to get more total performance at the same cost by purchasing another properly
matched solar panel instead of a more expensive MPPT solar charger.
A common mistake for evaluating MPPT performance
is to compare their (lower) solar input current with
(higher) output battery current, and thinking this additional current is solely due to the MPPT charger. This is
incorrect, and will give an exaggerated impression of its advantage. A comparison must be done by changing to the
PWM controller and then comparing battery currents.
2. Technical Specifications:
Regulation type...........................................
PWM
Solar panel open-circuit voltage..................55V maximum
Solar panel nominal voltage.......................12V - 24V, matched to the battery voltage:
Vpp about 16-18+Volts for 12-
24V systems, Vpp about 32-36+ for 24V systems
Nominal Battery voltage............................12V - 24V
Required operational current.....................While sun shining: 25mA. Solar dark: 1mA max
Maximum Battery voltage............. ...........35V
Battery type...............................................AGM, Gel, or flooded lead-acid
Solar-panel peak current...........................Max 31A for full efficiency. May be safely used with panels up to 45A,
however charging current will be reduced to protect charger.
MINIMUM in/out power efficiency at 30A: ...97.5% (12V systems) 98.5% (24 V systems)
MINIMUM in/out power efficiency at 15A: ...99%
Battery capacity.........................................10 to 10,000 amp hours
Terminal block wire gauge.....................Up to 6 AWG.
(Larger stranded cables you can remove some strands to fit)
Charging profiles.....................................Three stages and optional fourth stage
Ambient temperature................................0 ºF to +140 ºF (−18 ºC to +60 ºC)
Dimensions.............................................. in.: 3 width X 4 1/4 length X 2 3/4 depth; cm: 7.6 width X 10.8 length X 7
depth
3. General Solar Charging system suggestions and considerations
Balancing batteries with solar:
If you intend to charge your batteries mainly or only by solar panels, it's
recommended by many battery companies to properly balance the battery storage capacity with adequate solar. Too
much battery for solar energy provided can result in undercharging that can reduce battery performance and life.
Peak solar panel currents of from 1/10 to 1/4 of the battery "C/20" ampere hour value are often recommended. For
example, solar panels that deliver up to 24 Amps could be optimally paired with a battery of 100 to 240 amp-hour
capacity system. Otherwise you might want to provide an additional source such as generator or grid tied charger to
insure that your batteries frequently get a full charge.
Solar as excellent adjunct to generator charging:
A generator can put a lot of energy into the batteries in a
relatively short time when they are not too close to being fully charged. As they become more fully charged,
batteries gradually accept energy at a lower rate—So charging them to full requires more hours than is usually
desirable to run a generator. Even if you don’t plan to use only solar for charging, solar panels are well suited to
deliver the last 20% of charge—which would otherwise require long generator times running inefficiently at a low
charging rate. This will enhance your battery life and reduce generator wear.
You can use other chargers along with this one:
If other chargers are also used with your system, they can be
