What is the CCR controller?
The control electronics of the CCR — it turns the brightness step into a target current and keeps the loop current at it.
The CCR controller is the control electronics of the constant-current regulator. It takes the brightness step command from the local selector or from remote control, turns it into a target current, measures the actual output current with a current sensor, and adjusts the power stage until the two match.
In a closed-loop CCR, such as a thyristor type, the controller is what makes the circuit constant-current; the power stage only supplies the power. It also watches for faults such as an open circuit or overload, shows the state on the CCR display, and sends status and alarm signals to the airfield lighting control system. Designs and terminology vary between manufacturers; a ferroresonant CCR regulates mainly through its transformer rather than an electronic feedback loop.
- Receive. Take the brightness step from the local or remote command.
- Set. Convert the step into the target current.
- Measure. Read the output current from the current sensor.
- Compare. Check the measured current against the target.
- Correct. Adjust the power stage to raise or lower the output voltage.
- Report. Send status and any alarms to the display and control system.
Frequently Asked Questions
Q1What is a CCR controller?
The control electronics of a constant-current regulator. It takes the brightness step command, works out the target current, checks the actual output current and adjusts the power stage until the two match.
Q2What does the controller actually control?
The power stage, which sets how much voltage the CCR delivers to the loop. By changing that voltage, the controller keeps the loop current at the target value as the load changes.
Q3How does the controller know the current is correct?
A current sensor on the output measures the loop current and feeds the value back to the controller. The controller compares it with the target continuously and corrects any difference.
Q4Where does the brightness step come from?
From a local selector at the CCR or from a remote command sent by the airfield lighting control system. The controller converts the chosen step into the target current for that step.
Q5What else does the controller do?
It watches for faults such as an open circuit or overload, shows the state on the CCR display, and sends status and alarm signals to the control system. The exact functions depend on the CCR design.
Q6What happens if the controller or its sensor fails?
This depends on the design. The CCR may shut down, or it may no longer hold the correct current even though the loop itself is healthy. Follow the manufacturer's manual when diagnosing it.
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