Block Diagram Operation Manual Electrical Specs. Mechanical Info.
Transfer Switch: This is a solid-state switch that connects the UPS output to one of two sources. If the Input Supply is above 10.8VDC, the switch uses this as the source and the battery is disconnected from the circuit breaker. If the Input Supply is below 10.8VDC, the switch uses the battery as the source and the Input Supply is disconnected from the circuit breaker. The transfer from the Input Supply to internal battery takes less than a millisecond. Circuit Breaker: To protect the unit, a solid-state circuit breaker trips at between 3.5A and 7.0A. This completely disconnects the UPS Output Power pin. The circuit breaker latches in this state until the unit's mating connector is removed and then reconnected (assuming the overload has first been removed). When the circuit breaker trips, Signal F (fault) goes high to indicate the fault. uP - Controller: The unit's microprocessor-controller is powered by either the Input Supply (if present) or by the unit's internal battery (if enabled). This device controls the various solid-state switches, monitors the battery voltage, and generates the LED signals. Signal C (charging) has two functions. When the Input Power is above 10.8V, this signal is on whenever the battery charger is charging the battery and goes off when the charging is complete. When the Input Power is less than 10.8V, the microprocessor monitors the battery and reports its voltage by flashing on and off. Please see the Operation Manual for a detailed description of this. Signal P (power) is on when the Input Power is above 10.8V and off otherwise. Battery Charger: This is a switch-mode, buck/boost, enhanced 3-mode unit that can generate the proper battery charging voltage over the complete Input Supply voltage range. When the Input Supply is at a normal automotive battery system voltage (or higher), the charger can supply approximately 1.0A. The charger continues to operate at Input Supply voltages down to 6V. However, its current output drops considerably as its input voltage is reduced (0.25A at 6V input). Because the charger continues to operate down to 6V input, it can contribute its output current to the UPS Output Power pin. This, even when the internal battery is connected to the output (as it would be if the Input Supply dropped to 6V). Battery Disconnect: This also is a solid-state switch and has two functions. When the battery is connected to the UPS Output Power pin, the microprocessor monitors the battery voltage. A SLA (sealed lead-acid) battery can be damaged if its open-circuit voltage is allowed to drop below 10.8V. Should this happen while the battery is connected to the Output Power pin, the microprocessor signals the Battery Disconnect switch to disconnect the battery and shutdown the UPS. Applying a proper voltage the the unit's Input Supply pin restarts the UPS and allows the battery to be reconnected and recharged. The second function of this switch is to allow long-term storage of the UPS when not in use. The Enable pin is connected to ground via the UPS mating connector. When the unit's mating connector is removed, the Enable pin is no longer grounded. This completely disconnects the battery so that the unit's long-term storage time is limited only by the battery's internal leakage.