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9400000-J0 Rev E
9. Operation
9.1 Main Rectifier States
Rectifier operation has five main states; each state is distinct and necessary for the operation of the rectifier.
• Off
• Start Delay
• Soft Start
• Normal Operation
• Turning Off
9.1.1 Off
The rectifier is in the Off state immediately after power is applied to the rectifier or after a rectifier shutdown (remote
or local shutdown, AC shutdown, OVP or thermal shutdown).
In this state the DC-DC converter is turned off and the controller monitors its inputs for the proper conditions to
begin the start up sequence.
When the conditions have been met for start up, the rectifier transitions to the Start Delay state.
9.1.2 Start Delay
When the rectifier is in the Start Delay state, the DC-DC converter is held off and still not sourcing power, waiting for
a given amount of time before transitioning to the next state.
The controller continues to monitor its inputs.
After the Start Delay state, the rectifier transitions to the Soft Start state.
NOTE:
Soft start, or current walk-in, gradually increases the voltage and current output of the rectifier upon startup.
This is done to reduce the instantaneous load on the AC source.
9.1.3 Soft Start
When the Soft Start state is entered, the rectifier is turned on and the output voltage and output current gradually
increased. If a load is present, the rectifier begins to source power.
When the voltage and current limit ramps have finished, the rectifier will transition to the Normal Operation state.
9.1.4 Normal Operation
The Normal Operation state is the state that the rectifier will be in performing all of the rectifier functions and features
specified herein.
From this state, the only valid transition is to the Turning Off state. This transition will happen if the rectifier is required
to shut down.
9.1.5 Turning Off
The Turning Off state is entered because a short delay is required before the rectifier actually turns off to take care of
any initialization requirements.
When this short delay has elapsed, a transition to the Off state is made.
9.2 Main Rectifier Modes
In addition to the main rectifier states, there is a set of main rectifier modes. These modes can be divided into two
categories, the output voltage mode and the output current/power mode.
