The Keithley 174 is a 30,000-count digital multimeter engineered for precision general-purpose measurements across AC/DC voltage, AC/DC current, and resistance. Delivering 0.013% basic DC accuracy with 0.1 microvolt DC voltage sensitivity, the instrument provides flexible ranging via manual, automatic, or remote modes. Input isolation reaches 10⁹Ω case-to-case, ensuring signal integrity in demanding measurement environments.
## Technical Specifications
**Display & Accuracy**
• 30,000-count display resolution
• Basic DC accuracy: 0.013%
• DC voltage sensitivity: 0.1 microvolt
• Settling time: 1 second to within 1 count of final reading
**Input Characteristics**
• Input resistance: 11 MΩ on 200 mV, 2 V, and 20 V ranges; 10 MΩ on 200 V and 1000 V ranges
• Input isolation: Greater than 1000 MΩ on 200 mV and 2 V ranges with all function buttons in the out position
• Normal mode rejection ratio: Greater than 60 dB at 50 Hz and 60 Hz
**Measurement Capabilities**
• Voltage: AC/DC to 1000 V peak
• Current: AC/DC measurements supported
• Resistance: 200 Ω to 2 MΩ ranges with ±(0.05% + 1–2 counts) accuracy
• Diode test: Junction voltage display to 2 V; +5 V open-circuit voltage
• dB mode: ±(0.02 dB + 1 count) accuracy above –78 dBm; 0.01 dB resolution above 5% of range
**Safety & Protection**
• Maximum allowable input: 1000 V DC or peak AC (less than 10 seconds per minute on 200 mV and 2 V ranges; 300 V RMS continuous); 450 V DC or peak AC for resistance measurements
• Fuse: 2 A, 250 V, 3AG, normal-blow (Keithley FU-13 or equivalent)
## Key Features
• Three ranging modes: manual, automatic, or remote control
• Compact form factor: 89 mm H × 235 mm W × 275 mm D; 1.8 kg
• Low power consumption: 12 VA
• Optional 6-hour battery pack (Model 1758)
## Operating Environment
• Operating temperature: 0°C to 50°C
• Operating humidity: Less than 80% RH to 35°C; derate 3% RH/°C from 35°C to 50°C
• Line voltage: 105–125 V or 210–250 V, 50–60 Hz (90–110 V available)
## Compatibility & Integration
Optional interfaces expand measurement capability: Model 1722 Digital Interface, Model 1723 IEEE Interface, Model 1740 AC Option, Model 1744 Ohmmeter Option, and Model 1745 Ammeter Option. Standard shrouded test leads (Model 1751) included.
