# Keithley 2231A-30-3 195W Triple Channel DC Power Supply (Pre-Owned) # Keithley 2231A-30-3 195W Triple Channel DC Power Supply (Pre-Owned) ## Key Features At A Glance - Three fully independent, isolated outputs — two channels at 0–30V/3A and one channel at 0–5V/3A - 195W total output power for energizing analog, digital, and mixed-signal circuits from a single instrument - Voltage setting accuracy of 0.06% + 20mV and current setting accuracy of 0.2% + 10mA - Linear-based design delivers low output noise of ≤1mVrms / ≤5mVp-p (20Hz–20MHz) - Series and parallel combination modes double output to 60V or 6A using the two 30V channels - 30 setup memory locations plus per-channel output timers (0.1s to 99999.9s) for repeatable testing - Output-to-output and output-to-chassis isolation up to 240V (DC + peak AC) for floating and grounded circuits - Optional 2231A-001 USB Adapter enables PC control and data upload for automated benchwork The Keithley 2231A-30-3 is a 195W triple channel DC power supply built around a linear regulation design. It provides two independently programmable 0–30V/3A outputs and a third 0–5V/3A output in a single benchtop enclosure, with all three channels electrically isolated from each other and from chassis ground. Keithley positions this supply for engineering and science student labs, service work, and electronic design. The three independent outputs let one instrument power the analog and digital sections of a printed circuit board simultaneously, support circuits referenced to different grounds (including transformer-isolated and optically isolated designs), and — by tying high and low terminals of two channels to a common reference point — supply bipolar circuits with positive and negative rails that can be varied together using the tracking function. ## Brand Heritage Keithley Instruments was founded in 1946 in Cleveland, Ohio. The company was acquired by Danaher Corporation in 2010, and in 2016 Danaher's test and measurement businesses — including Keithley and Tektronix — were spun off as Fortive Corporation. Keithley continues to operate as a Tektronix Company under Fortive, and the 2231A-30-3 datasheet carries both the Keithley and Tektronix Company markings. ## Accessories Supplied - Documentation CD with User Manual - Certificate of Calibration - Power Cord ## Product Core & Specifications Specification Value DC Output Rating Channel 1 Voltage 0–30 V Channel 1 Current 0–3 A Channel 2 Voltage 0–30 V Channel 2 Current 0–3 A Channel 3 Voltage 0–5 V Channel 3 Current 0–3 A Maximum Power 195 W Load Regulation Voltage ≤0.02% + 4 mV Current ≤0.2% + 3 mA Line Regulation Voltage ≤0.02% + 4 mV Current ≤0.2% + 3 mA Ripple and Noise (20 Hz–20 MHz) Voltage ≤1 mVrms / ≤5 mVp-p Current ≤6 mArms Setting Resolution Voltage 10 mV Current 1 mA Setting Accuracy Voltage ≤0.06% + 20 mV Current ≤0.2% + 10 mA Readback Resolution Voltage 10 mV Current 1 mA Readback Accuracy Voltage ≤0.06% + 20 mV Current ≤0.2% + 10 mA Isolation Voltage, Output to Chassis Any output can be isolated up to 240 V (DC + peak AC with AC limited to a maximum of 3 Vpk-pk and a maximum of 60 Hz) relative to the earth ground terminal. Isolation Voltage, Output to Output Any output can be isolated up to 240 V (DC + peak AC with AC limited to a maximum of 3 Vpk-pk and a maximum of 60 Hz) relative to any other output terminal. Tracking and Combination Modes Tracking Mode Maintains the ratio on the two 30 V output channels that is present when the control is activated. Combination V1 + V2 Series Mode Deliver up to 60 V when CH1 and CH2 are wired in series. Meter reads back combined voltage. Combination I1 + I2 Parallel Mode Deliver up to 3 A when CH1 and CH2 are wired in parallel. Meter reads back combined current. General Memory 30 setup memory locations Output Timer Range 0.1 s to 99999.9 s Display Vacuum fluorescent display Front Connections Power output jacks: 3-sets, safety-shrouded banana jacks Rear Connections DB9 connector for remote control Overtemperature Protection If the internal temperature of the supply exceeds 85°C, the supply will automatically turn off. EMC Compliance Conforms to European Union EMC Directive Safety Compliance Conforms to European Union Low Voltage Directive Power Line Ratings 110 VAC / 230 VAC ±10% Power Line Frequency 47 Hz–63 Hz Maximum Power Consumption 750 VA Operating Environment 0° to 40°C, 5% to 80% relative humidity at up to 40°C Storage Environment –20° to 70°C, 5% to 80% relative humidity up to 40°C, and 5% to 60% relative humidity from 40° to 70°C Height 88.2 mm (3.5 in) Width 214.5 mm (8.5 in) Depth 354.6 mm (14 in) Net Weight 7.10 kg (15.7 lbs) Shipping Weight 9.40 kg (20.7 lbs) Warranty 3 years **Important:** Each output can be isolated up to 240V (DC + peak AC with AC limited to a maximum of 3Vpk-pk and a maximum of 60Hz) relative to earth ground or to any other output terminal.**Important:** The Model 2231A-001 USB Adapter is an optional accessory and is not included with the base unit; order it separately to enable PC-based USB control and data transfer from the supply.Recommended pairing: the optional Keithley 2231A-001 USB Adapter (with USB cable) enables PC control of the supply and data upload from the outputs for combined analysis with other test data. ## About this used unit - Warranty included - Functional verification included - Standard Calibration Upgrade Options: No Calibration Required, NIST Traceable, Z540.1 or ISO 17025 with Data, Z540.3 Guardbanding with Data. - Note that unnecessary accessories may not be included (contact Test Architect to confirm). **Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.** ## Details - **Price:** 0.0 USD - 175.0 USD - **Vendor:** Keithley - **Type:** Dc Supply - **Tags:** DC Power Supply, Keithley, Manufacturers, Power Supplies & Loads, product_manual_group_2, Product_used ## Variants | Variant | Price | Available | |---------|-------|-----------| | None | 0.00 USD | In stock | | NIST Traceable | 105.00 USD | In stock | | NIST Traceable with Full Data | 126.00 USD | In stock | | ISO IEC 17025 Accredited | 175.00 USD | In stock | ## Images - 2231A-30-3 Keithley DC Power Supply --- > Source: [ValueTronics](https://valuetronics.com/products/2231a-30-3-keithley-dc-power-supply-used) > Updated: 2026-05-30