The Keithley 175A is a 4.5-digit autoranging digital multimeter engineered for precision DC and AC measurements across voltage, current, and resistance. Built for both benchtop and portable field use, it delivers True RMS AC readings, manual or automatic range selection, and a 100-point data logger with Min/Max hold capability. The backlit LCD display and relative measurement functions make it practical for troubleshooting and verification tasks in manufacturing, service, and design environments.
Technical Specifications
Display & Interface
• 4.5-digit LCD, 0.5 inch character height
• Electroluminescent backlight for low-light operation
• Polarity, function, range, and status indicators
DC Voltage
• Range: 10 µV to 1000 V
• Basic accuracy: 0.03%
• Input impedance: 11 MΩ (200 mV and 2 V ranges); 10 MΩ (20 V, 200 V, 1000 V ranges)
• Normal mode rejection: >60 dB at 50 Hz, 60 Hz ±0.15%
• Settling time: 1 second to within 1 count
• Maximum input: 1000 V DC or peak AC (300 V rms continuous; <10 seconds per minute for 200 mV and 2 V)
True RMS AC Voltage
• Range: 10 µV to 750 V
• Bandwidth: 100 kHz typical; 300 kHz at 3 dB
• Crest factor: 3
• Input impedance: 11 MΩ || <75 pF (200 mV, 2 V); 10 MΩ || <75 pF (20 V, 200 V, 1000 V)
• Settling time: 2 seconds to within 15 counts
• Temperature coefficient: ±(0.1 × applicable accuracy)/°C; ±(0.07% + 2)/°C for 50 Hz–10 kHz
• Maximum input: 750 V rms, 1000 V peak (300 V rms continuous; <10 seconds per minute for 200 mV)
DC Current
• Range: 10 nA to 10 A
• Overload protection: 2 A fuse (250 V) on mA input; 20 A for 15 seconds (unfused) on 10 A input
• Burden voltage: 0.3 V (200 µA–20 mA, 10 A ranges); 0.8 V (2000 mA range)
• Settling time: 1 second to within 1 count (mA ranges); 2 seconds to within 15 counts (10 A range)
True RMS AC Current
• Range: 10 nA to 2 A
• Overload protection: 2 A fuse (250 V) on mA input; 20 A for 15 seconds (unfused) on 10 A input
• Settling time: 2 seconds to within 15 counts
• Derating: 0.15% rdg./amp above 5 A for self-heating
Resistance
• Range: 10 mΩ to 200 MΩ
• Basic accuracy: 0.05% + 2 counts (200 Ω range)
• Open-circuit voltage: +5 V
• Settling time: 2 seconds to within 1 count on range
dB Mode
• Reference: 600 Ω
• Accuracy: ±(0.02 dB + 1 count) above -78 dBm
• Resolution: 0.01 dB above 5% of range
– Key Features
• Autoranging and manual range selection
• 100-point data logger with Min/Max hold
• Relative measurement function
• True RMS AC measurement for harmonically distorted waveforms
– Typical Applications
• Benchtop verification and component testing
• Field service and troubleshooting
• Process monitoring and quality assurance
• Audio and telecommunications measurement
– Compatibility & Integration
Portable form factor supports both stationary lab use and mobile field deployment.
