Kepco BOP100-4M Bipolar Operational Power Supply: High Speed Voltage and Current Source

Product Overview

The Kepco BOP100-4M is a bipolar operational power supply from the BOP (Bipolar Operational Power) series, rated at 100 volts and 4 amperes. This power supply is capable of four-quadrant operation, meaning it can source and sink both voltage and current, making it suitable for applications requiring controlled charging and discharging of reactive loads such as capacitors, inductors, and batteries. The BOP100-4M functions as a high-speed, programmable voltage or current source with a built-in amplifier that can be controlled from an external analog signal or via digital interfaces. It is widely used in laboratory testing, component characterization, and industrial automation where precise, bipolar power is required.

Key Features of Kepco BOP100-4M

The BOP100-4M features a true four-quadrant output, automatically transitioning between source and sink modes as the load demands. The output can be programmed as a voltage source (with current limiting) or as a current source (with voltage limiting), selectable by the user. The power supply incorporates a high-gain DC amplifier with a bandwidth sufficient for many dynamic applications, accepting analog control signals of ±10 V or ±5 V. The unit includes digital control via RS-232 or GPIB (IEEE-488) interfaces, allowing remote programming of output voltage, current limit, and operating modes. The front panel features a bright LED display showing output voltage and current, along with control knobs for local adjustment.

The BOP100-4M is built with linear regulator design, providing low output noise and ripple compared to switching supplies. The output is fully protected against short circuits, overcurrent, and overtemperature conditions, with automatic recovery. The power supply includes an output enable/disable function and a status indicator for over temperature and over voltage. The unit is designed for benchtop or rack mounting (19-inch rack adapters available). The BOP series is known for its fast slewing rate, allowing the output to change rapidly in response to programming commands or external signals. The BOP100-4M includes a crowbar overvoltage protection circuit that can be set to trip at a user-defined voltage, protecting sensitive loads from excessive voltage.

Technical Specifications

• Manufacturer: Kepco Inc.

• Part Number: BOP100-4M (also BOP1004M)

• Series: BOP (Bipolar Operational Power Supply)

• Product Type: Bipolar Operational Power Supply / Power Amplifier

• Output Voltage Range: -100 V to +100 V

• Output Current Range: -4 A to +4 A

• Power Rating: 400 W (source or sink)

• Operation Quadrants: 4 (source/sink voltage and current)

• Control Methods: Local (knobs), analog (±10 V), digital (RS-232, GPIB)

• Slew Rate: Typical 0.5 V/µs (voltage mode), 10 A/ms (current mode)

• Output Ripple: < 5 mVrms typical

• Stability: 0.01% over 8 hours

• Protections: Short circuit, overcurrent, overtemperature, crowbar OVP

• Display: Digital LED, 4-digit voltage and current

• Input Power: 120/240 V AC selectable, 50/60 Hz

• Dimensions: Standard 19-inch rack width (1/2 rack), 5.25 inches height

• Operating Temperature: 0 to +55 °C

• Cooling: Internal fan

Functional Description

The Kepco BOP100-4M operates as a precision voltage or current amplifier. In voltage mode, the user programs a desired output voltage (e.g., via analog input or digital command), and the power supply adjusts its output to achieve that voltage while limiting the current to the set value. If the load attempts to draw more than the current limit, the supply automatically transitions to current mode, lowering the voltage to maintain the set current. In current mode, the opposite occurs: the supply tries to force the programmed current, and if the load voltage would exceed the voltage limit, it limits the current accordingly. The four-quadrant capability means the BOP can absorb power from the load (e.g., when driving an inductive load during a downward voltage ramp) and dissipate it internally. The internal amplifier is a linear design, providing low distortion and noise, making it suitable for driving coils, piezoelectric actuators, and for testing batteries and capacitors. The remote sensing terminals allow the supply to compensate for voltage drops in the load leads, maintaining accurate voltage at the load.

Applications

The Kepco BOP100-4M is used in research and development laboratories, production test systems, and industrial automation where bipolar, low-noise power is required. Typical applications include driving electromagnetic coils for magnetic field generation, testing of automotive batteries and supercapacitors, powering piezoelectric stacks for precision positioning, simulating solar cells and batteries for inverter testing, and as a general-purpose power amplifier for control systems. The BOP series is also used in materials research for magnetization and dielectric testing.