Protection Circuits
TH-42PD25U-P Protection Circuits
Protection circuits are incorporated in the unit to prevent the failure of a single circuit or
a component from creating catastrophic damage.
A shutdown occurs when an over voltage condition, a short, or a drop in any of the
voltage lines occurs. Also, shutdown occurs when any of the fans draw more current
than normal.
The microprocessor IC9709 monitors the SOS lines to detect a shutdown condition and
relays the information to the main microprocessor to shut the unit down.
Figure 27 - TH-PD25U_SOS Detect Circuit
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