Kepco BOP 1000M Troubleshooting Application

6.2 Calibration Process and Password Protection

All calibration of BOP 1KW is performed through remote interface or front panel keypad, and the calibration coefficients are stored in non-volatile memory and password protected (default password can be obtained from Kepco). The steps are as follows:

Enter calibration mode (via menu or send CAL: STAT ON).

Connect the high-precision multimeter to the output terminal according to the prompts.

Calibrate the zero point, positive and negative full-scale voltage, and positive and negative full-scale current in sequence.

Save calibration parameters.

Common faults: If the device output deviates from the set value by more than 0.5% and cannot be adjusted, it is usually due to loss of calibration data (battery depletion or motherboard failure). At this point, it is necessary to recalibrate or replace the motherboard.

6.3 Interpretation of Typical Fault Codes

OVP (Overvoltage Protection): If there is a voltage source (such as a battery) on the load side that is higher than the rated voltage of the BOP, or if the internal voltage feedback loop fails. Disconnect the load first and measure whether the output is normal; If normal, check if the load contains back electromotive force.

OCP (Overcurrent Protection): Load short circuit or low current setting value. Check the load impedance and confirm that the current limit setting is higher than the peak demand.

FAN malfunction: Internal fan stalling or loss of speed signal. Clean the fan blades, and if ineffective, replace the fan (standard 92mm 12V).

AC FAIL: Input voltage exceeds the range of 176-264Vac, or PFC circuit failure. Check the voltage of the power grid, if it is normal, it needs to be repaired.

6.4 Parallel and Series Operations

Up to 5 BOPs of the same model can be connected in parallel (increasing current), and up to 3 BOPs can be connected in series (increasing voltage). When connecting in parallel, it is necessary to use a current sharing cable (contact Kepco for customization), and set one as the master and the rest as slaves. When connecting in series, please note that the total voltage should not exceed the insulation withstand voltage of any one unit (usually ± 100V models can reach ± 200V after being connected in series, but the grounding midpoint is required).

Key safety reminder: After series connection, the common mode voltage of each BOP will increase. It is necessary to ensure that the grounding potential of all series connected units is consistent and the output does not exceed the ground withstand voltage (usually ± 150V).

Chapter 7 Maintenance and Lifecycle Management

7.1 Regular inspection items

Every 6 months: Use an internal resistance meter to measure the insulation resistance of the output terminal to ground, which should be greater than 10M Ω; check whether the internal fan filter (if installed) is blocked.

Every year: Perform a complete calibration, especially for current measurement accuracy, as aging of the current divider can affect the accuracy of the absorption mode.

Every 3 years: Check the internal electrolytic capacitors (especially PFC bus capacitors) for bulges or leaks. For devices that frequently operate in absorption mode, capacitors age faster.

7.2 Replacement strategy after shutdown

Although this article mainly focuses on the Kepco BOP 1000M series, the series is still in production. If there is a future shutdown or shortage of maintenance spare parts, the following replacement directions can be considered:

Upgrade directly to BOP 2KW series (higher power)

Use other brands of high-voltage four quadrant power supplies (such as California Instruments, Chroma), but pay attention to whether their energy feedback efficiency and analog bandwidth match.

For scenarios that only require source functionality, it can be downgraded to a single quadrant power supply+independent electronic load, but the system complexity will significantly increase.

It is recommended that users backup the calibration data and configuration parameters of each device in advance (by reading all settings through GPIB), so as to quickly reproduce the working status during future replacements.