# B&K Precision 5491B 4 3/4 Digit True RMS Bench Multimeter (Pre-Owned) # B&K Precision 5491B 4 3/4 Digit True RMS Bench Multimeter (Pre-Owned) ## Key Features At A Glance - Up to 50,000 count display resolution (4-3/4 digits on 5491B; 20,000 count / 4-1/2 digits on 2831E) - Basic VDC accuracy of up to 0.02% (5491B); 0.03% on 2831E - Dual VFD display shows two measurements simultaneously - AC+DC True RMS measurement with max crest factor of 3.0 at full scale - Up to 25 readings per second with selectable slow, medium, and fast measurement rates - AC voltage to 100 kHz and AC current to 20 kHz frequency range - Built-in math functions: Rel, Max/Min, dBm, dB, %, Hold, and Compare (Limit) for Pass/Fail testing - CAT I 1000 V / CAT II 300 V input protection; USB standard, RS-232 on 5491B; SCPI-compatible The B&K Precision 2831E and 5491B are bench-style True RMS digital multimeters built around a dual-line VFD display that lets the operator view two related measurements at once — for example an AC voltage and its frequency, or a DC voltage shown simultaneously in volts and dB. The 2831E provides a 20,000-count display with 4-1/2 digit resolution, while the 5491B steps up to a 50,000-count display with 4-3/4 digit resolution and tighter basic DC voltage accuracy. Per the datasheet, these meters are positioned for education, service and repair, and manufacturing applications requiring basic and reliable measurements. The built-in math operations — Rel, Max/Min, dBm, dB, %, and Hold — are called out as a convenient tool for teaching basic measurement concepts, while the Compare (limit) mode supports Pass/Fail bench testing with an audible alarm when readings fall outside a user-defined window. ## Brand Heritage B&K Precision Corporation, founded in 1951 as Dynascan Corporation in Chicago, has manufactured electronic test instruments under the B&K Precision brand for more than seven decades. The company is now headquartered in Yorba Linda, California and continues to operate as B&K Precision with no recent rebranding. ## Compare Other Models in This Series The 2831E and 5491B share an identical mechanical platform, identical measurement functions (DCV, ACV, DCI, ACI, resistance, continuity, diode, frequency, and period), identical front-panel layout, and identical accessory complement. They differ in display resolution, basic measurement accuracy, communication interface options, and warranty term, allowing a buyer to choose between two specification tiers within the same product family. The datasheet groups both meters under a single 'True RMS Bench Multimeters with Dual Display' family and presents their specifications side by side in every measurement table, making model-to-model comparison straightforward for buyers evaluating which tier matches their accuracy and connectivity requirements. Each pre-owned model below is its own dedicated product page with condition-matched pricing, availability, and accessory disclosure. Selecting the correct page ensures that the quote you receive matches the specific unit being sold. The primary specification difference is display resolution and DC accuracy: the 2831E provides 20,000-count, 4-1/2 digit resolution with 0.03% basic VDC accuracy, while the 5491B provides 50,000-count, 4-3/4 digit resolution with 0.02% basic VDC accuracy. The 5491B also offers tighter accuracy across AC voltage, current, and resistance ranges as detailed in the specification tables. The second differentiator is connectivity and warranty: both meters include USB as standard, but only the 5491B includes RS-232. Warranty terms also differ — one year on the 2831E and three years on the 5491B. The comparison table that follows summarizes the measurement-range and resolution differences for quick reference. Model Display Resolution Basic VDC Accuracy Interface **5491B** 50,000 count (4 3/4 digits) 0.02% USB (Virtual Com) and RS232 2831E 20,000 count (4 1/2 digits) 0.03% USB (Virtual Com) Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below. ## Accessories Supplied - Test leads - Power cord - Spare fuse - Operation Manual - Calibration certificate and test report ## Product Core & Specifications Category Specification 2831E 5491B DC Voltage (Accuracy ± (% of reading + % of range), 23 °C ± 5 °C, Slow rate, 1 year) Range 1 Range / Resolution / Full Scale / Accuracy / Input Impedance 200.00 mV / 10 µV / 210.00 / 0.04%+0.09% / >10 MΩ 500.00 mV / 10 µV / 510.00 / 0.02%+0.016% / >10 MΩ Range 2 Range / Resolution / Full Scale / Accuracy / Input Impedance 2.0000 V / 100 µV / 2.1000 / 0.04%+0.08% / >11.1 MΩ 5.0000 V / 100 µV / 5.1000 / 0.02%+0.008% / >11.1 MΩ Range 3 Range / Resolution / Full Scale / Accuracy / Input Impedance 20.000 V / 1 mV / 21.000 / 0.04%+0.09% / >10.1 MΩ 50.000 V / 1 mV / 51.000 / 0.02%+0.008% / >10.1 MΩ Range 4 Range / Resolution / Full Scale / Accuracy / Input Impedance 200.00 V / 10 mV / 210.00 / 0.04%+0.09% / 10 MΩ 500.00 V / 10 mV / 510.00 / 0.02%+0.008% / 10 MΩ Range 5 Range / Resolution / Full Scale / Accuracy / Input Impedance 1000.0 V / 100 mV / 1010.0 / 0.04%+0.08% / 10 MΩ 1000.0 V / 100 mV / 1010.0 / 0.02%+0.008% / 10 MΩ AC Voltage (True RMS, Slow rate, 1 year, 23 °C ± 5 °C, Max crest factor 3.0 at full scale) Range 1 Range / Resolution / Full Scale 200.00 mV / 10 µV / 210.00 500.00 mV / 10 µV / 510.00 Range 2 Range / Resolution / Full Scale 2.0000 V / 100 µV / 2.1000 5.0000 V / 100 µV / 5.1000 Range 3 Range / Resolution / Full Scale 20.000 V / 1 mV / 21.000 50.000 V / 1 mV / 51.000 Range 4 Range / Resolution / Full Scale 200.00 V / 10 mV / 210.00 500.00 V / 10 mV / 510.00 Range 5 Range / Resolution / Full Scale 750.0 V / 100 mV / 757.5 750.0 V / 100 mV / 757.5 ACV Accuracy 50~20 kHz (mid range) 50~20 kHz 0.4%+0.05% 0.35%+0.02% DC Current (Slow rate, 1 year, 23 °C ± 5 °C) Range 1 Range / Resolution / Full Scale / Accuracy / Burden Voltage & Shunt 2.0000 mA / 0.1 µA / 2.1000 / 0.08%+0.025% / <0.3 V / 100 Ω 5.0000 mA / 0.1 µA / 5.1000 / 0.05%+0.01% / <0.6 V / 100 Ω Range 2 Range / Resolution / Full Scale / Accuracy / Burden Voltage & Shunt 20.000 mA / 1 µA / 21.000 / 0.08%+0.02% / <0.04 V / 1 Ω 50.000 mA / 1 µA / 51.000 / 0.05%+0.008% / <0.06 V / 1 Ω Range 3 Range / Resolution / Full Scale / Accuracy / Burden Voltage & Shunt 200.00 mA / 10 µA / 210.00 / 0.08%+0.02% / <0.3 V / 1 Ω 500.00 mA / 10 µA / 510.00 / 0.05%+0.008% / <0.6 V / 1 Ω Range 4 Range / Resolution / Full Scale / Accuracy / Burden Voltage & Shunt 2.0000 A / 100 µA / 2.1000 / 0.3%+0.025% / <0.05 V / 10 mΩ 5.0000 A / 100 µA / 5.1000 / 0.25%+0.01% / <0.1 V / 10 mΩ Range 5 Range / Resolution / Full Scale / Accuracy / Burden Voltage & Shunt 20.000 A / 1 mA / 21.000 / 0.3%+0.025% / <0.6 V / 10 mΩ 20.000 A / 1 mA / 21.000 / 0.25%+0.01% / <0.6 V / 10 mΩ AC Current (True RMS, AC Coupling, Slow rate, 1 year) Range 1 Range / Resolution / Full Scale 2.0000 mA / 0.1 µA / 2.1000 5.0000 mA / 0.1 µA / 5.1000 Range 2 Range / Resolution / Full Scale 20.000 mA / 10 µA / 21.000 50.000 mA / 10 µA / 51.000 Range 3 Range / Resolution / Full Scale 200.00 mA / 100 µA / 210.00 500.00 mA / 100 µA / 510.00 Range 4 Range / Resolution / Full Scale 2.0000 A / 1 mA / 2.1000 5.0000 A / 1 mA / 5.1000 Range 5 Range / Resolution / Full Scale 20.000 A / 10 mA / 21.000 20.000 A / 10 mA / 21.000 Resistance (Slow rate, 1 year, 23 °C ± 5 °C) Range 1 Range / Resolution / Test current / Accuracy 200.00 Ω / 10 mΩ / 0.5 mA / 0.3%+0.05% 500.00 Ω / 10 mΩ / 0.5 mA / 0.10%+0.01% Range 2 Range / Resolution / Test current / Accuracy 2.0000 kΩ / 100 mΩ / 0.45 mA / 0.10%+0.025% 5.0000 kΩ / 100 mΩ / 0.45 mA / 0.10%+0.008% Range 3 Range / Resolution / Test current / Accuracy 20.000 kΩ / 1 Ω / 45 µA / 0.10%+0.025% 50.000 kΩ / 1 Ω / 45 µA / 0.10%+0.008% Range 4 Range / Resolution / Test current / Accuracy 200.00 kΩ / 10 Ω / 4.5 µA / 0.10%+0.025% 500.00 kΩ / 10 Ω / 4.5 µA / 0.10%+0.008% Range 5 Range / Resolution / Test current / Accuracy 2.0000 MΩ / 100 Ω / 450 nA / 0.15%+0.025% 5.0000 MΩ / 100 Ω / 450 nA / 0.15%+0.008% Range 6 Range / Resolution / Test current / Accuracy 20.000 MΩ / 1 kΩ / 45 nA / 0.3%+0.05% 50.000 MΩ / 1 kΩ / 45 nA / 0.3%+0.01% Continuity Range Range / Resolution / Full Scale / Test current / Accuracy 200 Ω / 100 mΩ / 999.9 / 0.5 mA / 0.1%+0.3% 500 Ω / 100 mΩ / 999.9 / 0.5 mA / 0.1%+0.04% Open circuit voltage   <5.5 VDC Test current   around 0.5 mA DC Diode Range / Resolution / Full Scale / Test current Med rate 2.0000 V / 100 µV / 2.3000 V / 0.5 mA (Approx.) Frequency (ACV Range 200 mV \[500 mV for 5491B\] to 750 V) 10 Hz Best Resolution / Full Scale / Accuracy / Input Sensitivity 100 µHz / 9.9999 / 0.05%+0.02% / 200 mV rms 10~100 Hz Best Resolution / Full Scale / Accuracy / Input Sensitivity 1 mHz / 99.999 / 0.01%+0.02% / 300 mV rms 100~100 kHz Best Resolution / Full Scale / Accuracy / Input Sensitivity 10 mHz / 999.99 / 0.01%+0.008% / 300 mV rms 100k~1 MHz Best Resolution / Full Scale / Accuracy / Input Sensitivity 10 Hz / 999.99 / 0.01%+0.008% / 500 mV rms Period (ACV Range 200 mV \[500 mV for 5491B\] to 750 V) 1~10 µs Best Resolution / Full Scale / Accuracy / Input Sensitivity 0.1 ns / 9.9999 / 0.01%+0.008% / 500 mV rms 10 µs~10 ms Best Resolution / Full Scale / Accuracy / Input Sensitivity 1 ns / 9.9999 / 0.01%+0.008% / 300 mV rms **Important:** Maximum input rating: CAT I 1000 V / CAT II 300 V. In the 20 A current range, currents above 10 A are readable for a maximum of 20 seconds.**Important:** In the 20 A range, currents greater than 10 A up to 20 A (DC or AC) are readable for 20 seconds maximum.**Important:** For measuring resistance above 100 kΩ, it is recommended to use a shielded test cable to eliminate noise interference that might be induced into the test leads.**Important:** Warm-up time of at least 30 minutes is required before specifications apply.**Important:** AC voltage 750 V range: limit at 40 kHz or ≤ 3×10^7 Volt-Hz. ## 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:** 425.0 USD - **Vendor:** B&K Precision - **Type:** Multimeter - **Tags:** BK Precision, Manufacturers, Meters & DAQ, Multimeter, product_manual_group_3, Product_used ## Variants | Variant | Price | Available | |---------|-------|-----------| | Default Title | 425.00 USD | In stock | ## Images - B&K Precision 5491B 4 3/4 Digit True RMS Bench Multimeter (Pre-Owned) --- > Source: [ValueTronics](https://valuetronics.com/products/5491b-bkprec-multi-met-used) > Updated: 2026-05-30