The Keithley 2015 is a 6½-digit Total Harmonic Distortion (THD) Multimeter that combines standard high-performance digital multimeter capabilities with specialized audio band quality measurement and analysis. It integrates a dedicated sine wave generator and built-in processing to measure THD, THD+N, and SINAD across the audio frequency spectrum (20 Hz to 20 kHz). Sharing a foundation with the industry-standard Keithley 2000 DMM, it allows engineers to consolidate broad AC/DC voltage, current, resistance, frequency, and distortion measurements into a single compact, half-rack instrument.

Specifications

General

ParameterValue
InterfacesGPIB (IEEE-488.2), RS-232
DisplayVacuum Fluorescent Display (VFD)
Data Buffer Capacity1024 readings
Warm-up Time1 hour to rated accuracy

Physical

ParameterValue
Power Supply100 V / 120 V / 220 V / 240 V ±10%, 45-66 Hz and 360-440 Hz
Operating Temperature0 to 50
Dimensions (W×H×D)213 x 89 x 370 mm
Weight4.2

General Specifications

ParameterValue
Multimeter Resolution6½ Digits
Form FactorHalf-rack, 2U height

DC Voltage Characteristics

ParameterValue
DC Voltage Ranges100 mV, 1 V, 10 V, 100 V, 1000 V
Maximum Resolution (DCV)100 nV
Input Resistance>10 GΩ (100 mV, 1 V, 10 V ranges); 10 MΩ ±1% (100 V, 1000 V ranges)

AC Voltage Characteristics

ParameterValue
AC Voltage Ranges100 mV, 1 V, 10 V, 100 V, 750 V
Maximum Resolution (ACV)100 nV
AC Bandwidth3 Hz to 300 kHz

Current Characteristics

ParameterValue
DC Current Ranges10 mA, 100 mA, 1 A, 3 A
DC Current Resolution10 nA
AC Current Ranges1 A, 3 A

Resistance Characteristics

ParameterValue
Measurement Method2-Wire and 4-Wire
Resistance Ranges100 Ω, 1 kΩ, 10 kΩ, 100 kΩ, 1 MΩ, 10 MΩ, 100 MΩ
Maximum Resolution (Resistance)100 µΩ

Additional Multimeter Functions

ParameterValue
Frequency Measurement Range3 Hz to 500 kHz
Built-in Math OperationsRel, Min/Max/Average/StdDev, dB, dBm, Limit Test

Audio Distortion Analysis

ParameterValue
Measurement FunctionsTHD, THD+N, SINAD
Distortion Frequency Range20 Hz to 20 kHz
Fundamental Voltage Range100 mV, 1 V, 10 V, 100 V, 750 V ranges

Audio Function Generator

ParameterValue
Waveform Output TypeSine wave
Amplitude RangeUp to 4 Vrms (single-ended) / Up to 8 Vrms (differential)
Frequency Range20 Hz to 20 kHz

Measurement Speeds and Triggering

ParameterValue
Maximum Reading Rate2000 readings/s (at 4.5 digits)

Audio Analysis

ParameterValue
Distortion Measurement TypesTHD, THD+N, SINAD
Digital Audio FiltersA-weighting, CCITT, CCIR, CCIR-ARM, C-message, 400Hz High-pass, 30kHz/80kHz Low-pass

Audio Generator

ParameterValue
Generator Output Impedance50 Ω or 600 Ω (selectable)
Generator Amplitude Resolution0.5 mV

Inputs

ParameterValue
Maximum DC Input Voltage1000V
Maximum AC Input Voltage750V rms
Maximum Input Current3A (fuse protected)

Environmental

ParameterValue
Storage Temperature-40°C to +70°C

Power

ParameterValue
Line Frequency Options50 Hz, 60 Hz, 400 Hz

Performance

ParameterValue
Common Mode Rejection Ratio (CMRR)140 dB (DC, with 1 kΩ unbalance)
Normal Mode Rejection Ratio (NMRR)60 dB (DC, at 50/60 Hz)
Input Bias Current< 30 pA @ 25°C
Overrange Capability120% of range except on 1000V, 750V, and 3A ranges

Inputs & Outputs

ParameterValue
External Trigger InputTTL compatible
Voltmeter Complete (VMC) OutputTTL compatible

Software/Control

ParameterValue
Programming LanguageSCPI (Standard Commands for Programmable Instruments)

Technology

Digital Multimeter with DSP-based Audio Analysis

Applications

Audio band quality measurements, Total Harmonic Distortion (THD) analysis, Telecommunications testing, General-purpose bench and automated testing