Debugging and troubleshooting of Basler AVC63-12/AVC125-10 voltage regulator

Use an ungrounded DC power supply (≤ 24 Vdc) with a series current limiting resistor (1 Ω per volt, power ≥ 1W/2), for example, a 24V power supply with a 24 Ω/24W resistor.

Connect the positive pole to F1 and the negative pole to F2, and turn on the power for about 10 seconds before disconnecting.

If the first attempt is unsuccessful, check if the power polarity is correct (positive to F1, negative to F2).

It is strictly prohibited to magnetize the generator while it is rotating, otherwise it may damage the regulator.

4.2 Voltage Setting (VLT ADJ)

Short circuit terminals 4 and 7 to make panel VLT ADJ effective. Rotate clockwise to increase the output voltage.

If remote voltage regulation is required: Remove the 4-7 short circuit, connect a 10k Ω (2W) potentiometer between 6a and 7, and turn the panel VLT ADJ clockwise to the maximum. At this point, the resistance of the external potentiometer increases, and the output voltage rises.

4.3 Stability Adjustment (STB)

Stability (STB) potentiometer is used to suppress voltage oscillation ("traveling car"):

Use an oscilloscope to monitor the voltage of the generator.

Under no-load conditions, rotate the STB counterclockwise until the voltage begins to oscillate slightly, and then rotate clockwise until it reaches a stable point.

Add various loads to verify dynamic response. If the response is too slow, it can be slightly counterclockwise; If oscillating, then clockwise. This adjustment needs to be repeated until there is no voltage overshoot or oscillation when switching between full load and no-load.

4.4 Frequency compensation (UF KNEE and slope selection)

Frequency compensation (also known as underfrequency turning) is used to automatically reduce the output voltage according to the V/Hz curve when the speed of the prime mover decreases, in order to prevent magnetic circuit saturation.

Turning point setting: At the rated frequency, first adjust UF KNEE counterclockwise, adjust VLT ADJ to make the voltage at the rated value, then rotate UF KNEE clockwise until the voltage starts to drop, and then counterclockwise adjust it back to the rated value - this point is the turning frequency (usually slightly lower than the rated frequency).

Slope selection: When terminal 8 is not connected to 6a, it is 2 PU V/Hz (steep slope); When connected to 6a, it is 1 PU V/Hz (gentle slope). The 400 Hz model is also applicable, and the actual curve shape is shown in Figure 1 and Figure 2.

4.5 Factory Calibration (FAC CAL) - Use with Caution

This potentiometer has been calibrated at the factory and users generally do not touch it. If there is an unexpected disturbance, the following steps can be taken to restore it:

Rotate FAC CAL counterclockwise to the end, and rotate the external pressure regulator (if any) clockwise to the end.

Slowly rotate FAC CAL clockwise until the output voltage reaches the required maximum value, at which point the factory calibration point is restored.

Parallel sag and line voltage drop compensation

5.1 Parallel Droop

When multiple generators are running in parallel, to avoid reactive power circulation, it is necessary to introduce reactive power droop characteristics. Detect the load current through CT (terminal 5/5A) and adjust the droop amount (0-10% adjustable) through DRP potentiometer. Increase the sag clockwise to make the reactive power distribution more balanced.

5.2 Line Drop Compensation (LDC)

When there is a long transmission line between the generator and the load, the impedance of the line will cause the voltage at the load end to be lower than that at the generator end. LDC connects CT in reverse (i.e. CT polarity reversed) and adjusts DRP to make the regulator "sense" the line voltage drop and increase the generator voltage for compensation. Note: LDC only compensates for voltage drop caused by line inductance and reactive load components, and does not compensate for resistive voltage drop.

Optional modules and extended functions

Remote voltage adjustment: external 10k Ω potentiometer (see 4.2).

Excitation limiter (EL 200): Provides rapid overexcitation limitation, and when the excitation current exceeds the set value, sends a signal to the regulator accessory input (terminals 2, 3) to lower the set point.

Power factor/reactive power controller (SCP 250): During grid connected operation, DC signals are injected through terminals 2 and 3 to adjust the regulator according to the set power factor or reactive power.

Current boost system (CBS 212): Provides additional excitation current boost to help clear faults or start large motors when voltage drops due to motor start-up or short circuit faults.

Manual voltage control (MVC-112): serves as a backup manual excitation control in case of regulator failure.

Surge current suppression module (ICRM-15): When there is already voltage on the power supply side, it can be connected to a regulator to suppress the instantaneous surge current when powered on.

Start trial operation and functional verification

According to the recommended startup process in the manual:

Check all wiring and confirm that there are no errors before starting the prime mover to the rated speed.