The B&K Precision 5491B benchtop digital multimeter (also known as a multitester) is a true RMS, auto-ranging meter for measuring current, voltage, resistance, and frequency in electrical testing and manufacturing applications and for teaching electrical engineering principles. The meter takes up to 25 readings per second. An audible continuity sensor confirms a circuit conducts electricity, and a diode test detects proper functioning of a circuit's diodes. The meter also measures period. The user can set high and low limits for pass/fail testing. The meter displays the present measurement or the highest or lowest reading in a session, for tracking sudden changes in readings. The meter can also express AC and DC voltage in decibels (dB), the power ratio of decibels to milliwatts (dBm), and percent of the reading relative to a preset reference value. The relative mode stores a reading in memory to use as a zero point for subsequent readings so that multiple readings can be compared. The dual LCD displays two readings at once, such as voltage and resistance. A hold function keeps a reading on the display, even after the meter has been disconnected. The user has a choice of slow, medium, or fast measurement rate; the faster the rate, the less precise the measurement. The USB and RS-232 interfaces connect the meter to a computer for data transfer and remote operation (cables not included), and is compatible with the SCPI programming language. The meter includes a set of detachable test leads, a spare fuse, a calibration certificate with test report, a 110/220V power cord, and instructions.

This true RMS (root mean square) meter provides accurate readings when measuring linear loads, such as standard induction motors and incandescent lights, where the current or voltage has an undistorted waveform, or nonlinear loads, such as electronic devices or motors, where the current or voltage has a distorted waveform. When turned on, the meter is in auto-ranging mode and automatically selects the correct operating range for the property being measured. It can be switched to manual-ranging mode, which allows the operator to choose the appropriate operating range. The LCD has a 50,000-count resolution, meaning it can display up to 49,999 units (4-3/4 digits) before the operating range needs to be changed. It meets International Electrotechnical Commission (IEC) safety standard 61010 and is certified for Category I installations up to 1000V (which covers protected electrical equipment such as small household appliances) and Category II installations up to 300V (which covers large household appliances and devices connected to a fixed power supply, such as refrigerators and air conditioners).

Specifications

H is height, the vertical distance from the lowest to highest point; W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back.

Multimeters are electrical test meters that measure multiple properties of an electrical circuit, such as current, voltage, resistance, capacitance, and continuity. Available in handheld or benchtop models, multimeters diagnose electrical problems in electrical equipment, wiring, and power supplies. A variety of probes, clamps, and leads can be used to connect the meter to a circuit or device. Multimeters display information either in analog or digital form. Factors that influence meter choice include the electrical properties to be measured, the anticipated range of results, and the desired level of protection against transient voltage. Safety ratings are based on International Electrotechnical Commission (IEC) standards for low-voltage test equipment. IEC 61010 delineates four overvoltage installation categories. In general, a meter with a category IV rating will provide more protection against transient voltages than a meter with a lower category rating.

B&K Precision manufactures test and measurement instruments for research and development, production-line testing, and electronic field service applications. The company, founded in 1951, is headquartered in Yorba Linda, CA. It meets International Organization for Standardization (ISO) standard 9001:2008 and is compliant with Restriction of Hazardous Substances (RoHS) and waste electronic and electrical equipment (WEEE) directives.

What's in the Box?

• B&K 5491B bench-top digital multimeter
• Set of test leads
• Spare fuse
• Calibration certificate and test report
• 110/220V power cord
• Instructions