Alpha Technologies Cordex HP CXRF 48-12kW - Manual (Page 30)

9400000-J0 Rev C 28
9. Rectifier States, Modes and Factory Defaults
9.1 Main Rectifier States
The rectifier operation can be broken up into five main states:
1. Off.
2. Start delay.
3. Soft start.
4. Normal operation.
5. Switching off.
Each state is characterized as being distinct and necessary for the operation of the rectifier. These states are
briefly described below.
9.1.1 Off State
The rectifier is in the Off state immediately after power is applied to the rectifier or after a rectifier shutdown. The
shutdown source may be a remote or local shutdown, an AC shutdown, an OVP shutdown, or a thermal shut-
down.
When the rectifier is in the Off state, the DC-DC converter is switched off and the CXC is monitoring 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 State
When the rectifier is in the Start Delay state, the DC-DC converter is held off and not sourcing power. The rectifier
is waiting for a set time before transitioning to the next state.
When the rectifier is in the Start Delay state, the CXC continues to monitor its inputs.
After the Start Delay state, the rectifier transitions to the Soft Start state.
9.1.3 Soft Start State
When the rectifier is in the Soft Start state, it is switched on. The output voltage and output current are gradually
increased. If a load is present, the rectifier begins to source power. This gradual increase reduces the instanta-
neous load on the AC source.
When the voltage and current limit ramp ups have finished, the rectifier transitions to the Normal Operation state.
9.1.4 Normal Operation State
During the Normal Operation state, the rectifier performs all of the rectifier functions and features.
From the Normal Operation state, the only valid transition is to the Switching Off state. This transition happens if
the rectifier is required to shut down.
9.1.5 Switching Off State
The Switching Off state is entered because a short delay is required before the rectifier actually switches off. The
short delay takes care of any initialization requirements.
When this short delay has elapsed, the rectifier transitions to the Off state.