ROGUE MPT-3024, Инструкция по установке и руководство пользователя

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12
!
The MPT-3024 is designed to operate with 12-volt and 24-volt
nominal PV arrays. The absolute maximum input voltage is 60 volts. A
24-volt nominal array, which may produce more than 45 volts open-circuit
on a cold sunny day, is the maximum recommended standard array
configuration to be used with this controller. A 36-volt nominal array will
normally have an open-circuit voltage of greater than 60 volts, which will
exceed the operating voltage of the MPT-3024. Use of arrays greater than
24 volts nominal is therefore not recommended. Above the 60-volt limit,
damage to the controller may result, which is not covered by warranty.
4.4 Optimize PV array power
A match between your PV array’s output and your battery bank is important for
proper maintenance of your batteries. Your PV array’s output, and also the
storage capacity of your battery bank, will be determined by several factors,
including the average amount of sun available to your site and the demand that
your loads present. Consult a system installer or an appropriate text for help in
calculating your needs.
The MPT-3024 will charge battery banks given any amount of current provided
(up to the maximum of 30 amps), but may not reach setpoints regularly, and
may not equalize properly, if current is constantly insufficient. Conversely, an
array that is oversized will consistently push the MPT-3024 to its maximum limit
of 30A. At and beyond this limit the power from the array is constrained and the
MPPT algorithm is overridden so that the controller does not exceed its
maximum current output. To avoid wasting available power, follow the guide-
lines given in Table 4.4.1 when sizing your array.
NEC 690-8 requires that the maximum PV short-circuit current (I
sc
.) used with
the MPT-3024 be limited to 24 amps. This means that the maximum array
power is limited to about 835 watts for a 24-volt array with a voltage of 34.8
volts at its maximum power point connected to a 24-volt battery, 418 watts for
a 12-volt array with a V
mp
of 17.4 volts connected to a 12-volt battery, and 418
watts for a 24-volt array with a V
mp
of 34.8 volts connected to a 12-volt battery.
The maximum usable PV array power when taking into consideration system
losses may be approximately calculated using the following formula, where Vb
is the battery voltage: PV(watts) = (30 x Vb) / 0.90