how to bypass shutdown in sg3525ap? i would like to make my circuit on and off only.

BTW: my circuit is from APC UPS ES-500. every 20 - 30 minutes the inverter is automatically shutdown. how to bypass or disable this shutdown function and make it on and off using ordinary SPST switch? thanks. suggestion are all welcome

PIC use is PIC16c72a

 

Hello,

Is there no description in the manual how to change the settings?
Disabeling the shutdown might lead to a to deep discharged battery when power is lost.

Bertus

 

From Freescale:

Since both the compensation and soft–start terminals
(Pins 9 and 8) have current source pull–ups, either can
readily accept a pull–down signal which only has to sink a
maximum of 100 mA to turn off the outputs. This is subject to
the added requirement of discharging whatever external
capacitance may be attached to these pins.
An alternate approach is the use of the shutdown circuitry
of Pin 10 which has been improved to enhance the available
shutdown options. Activating this circuit by applying a
positive signal on Pin 10 performs two functions: the PWM
latch is immediately set providing the fastest turn–off signal to
the outputs; and a 150 mA current sink begins to discharge
the external soft–start capacitor. If the shutdown command is
short, the PWM signal is terminated without significant
discharge of the soft–start capacitor, thus, allowing, for
example, a convenient implementation of pulse–by–pulse
current limiting. Holding Pin 10 high for a longer duration,
however, will ultimately discharge this external capacitor,
recycling slow turn–on upon release.
Pin 10 should not be left floating as noise pickup could
conceivably interrupt normal operation.

As you can see, there are multiple ways to shut down the chip and/or reasons it might shut down. Your inverter looks like a commercially made circuit, so I assume that the reason is not letting Pin 10 float.

Thus, disabling shut down could lead to failure to respond to a dangerous condition and destruction of the inverter and/or items being powered by it. A more productive route would be to find out why it is shutting down, such as overload, low input voltage, overheating, etc.

John

 

Hello,

Is there no description in the manual how to change the settings?
Disabeling the shutdown might lead to a to deep discharged battery when power is lost.

Bertus

@2 Bertus

No description on manual.
I'm not worrying to deeply discharge the battery because the inverter is connected after the charge/monitor controller.