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30-entry log. Under normal circumstances, each log entry will correspond to
one wake/sleep cycle (i.e. one day’s worth of data).
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Data logging will not operate properly in regions that receive 24-hour
sunlight during the summer months, if there is insufficient darkness to
cause the MPT-3024 to sleep once in a 24-hour period. In these situa-
tions, data will continue to accrue until the maximum values have been
reached (9.99kWh and 999.9Ah), and no log entries will be made.
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Disconnecting power to the MPT-3024 may cause the data log to
become corrupted. To minimize this risk, always disconnect the PV input
first and allow the controller to update the data log before disconnecting
battery power.
Data is logged with the most recent values saved in the 1st entry, and the
oldest values saved in the 30th entry. Each new entry will shift the existing
entries one down (i.e. 1st will become 2nd, 2nd will become 3rd, etc.). After 30
entries have been made, subsequent entries will push the oldest (30th) entry
off of the log to make room for the newest (1st). Log data is stored in
non-volatile memory, which is retained even when power to the controller is off.
The data log is updated upon entry into sleep mode. In some instances (during
wakeup in the morning and during shutdown at night), the MPT-3024 may
enter and exit sleep mode several times before settling into a steady state. In
order to prevent spurious log entries during these periods (which contain
negligible data, and which do not correspond to a genuine day’s worth of data),
the log will not be updated unless the Amp-hour meter has accumulated more
than 1.0Ah. It should be noted that excessive clouds or anything that obscures
the PV array during daylight (snow, for example) may invoke the sleep mode
with enough accumulated data to cause a log entry to be made, even though a
full day’s worth of data has not been logged.
When comparing log data from one day to another, keep in mind that the
output of the controller for any given day will depend largely on the state of the
batteries being charged that day and the demands of any active loads, in
addition to the amount of sunlight. Batteries that are almost fully charged will
cause much less accumulation for the watt-hour and amp-hour meters than
batteries which are discharged. Likewise, heavier loads will delay a full state of
Содержание MPT-3024
Страница 19: ...19 Figure 5 2 1 A typical day of operation for the MPT 3024 with 24 volt nominal array and 12 volt battery bank...
Страница 23: ...23 Figure 6 1 2 Efficiency curves for various PV battery combinations at 25o C...
Страница 29: ...29 Figure 11 2 2 Suggested wiring diagram...
Страница 36: ...36 Figure 12 1 1 Operational flowchart...
Страница 50: ...50 NOTES 50...
Страница 51: ...51 NOTES...
Страница 52: ...52 NOTES...