Specifications
Parameter Specification
Model Yokogawa CT9920
Type Current Transformer (CT)
Rated Current 50 A RMS
Maximum Current 100 A RMS (continuous)
Output Current 50 mA RMS (at 50 A input)
Turns Ratio 1000:1
Accuracy Class ±0.04% of reading (at 45-66 Hz)
Phase Error ±0.05° (at 45-66 Hz)
Frequency Range DC to 100 kHz
Operating Temperature -10°C to +50°C
Storage Temperature -25°C to +70°C
Safety Standards IEC 61010-1, CAT III 600 V
Connection BNC connector
Cable Length 3 meters (standard)
Dimensions Approximately 80 × 60 × 30 mm
Weight Approx. 300 g
Key Features
High accuracy: ±0.04% reading accuracy

Wide frequency range: DC to 100 kHz

Excellent phase characteristics: ±0.05° phase error

Compact and lightweight design

Easy connection with BNC connectors

Robust construction for industrial use

Safety compliance: CAT III 600 V rating

Electrical Characteristics
Rated input current: 50 A RMS

Maximum input current: 100 A RMS

Output current ratio: 50 mA output at 50 A input

Linearity: Excellent linearity within specified range

Temperature coefficient: Low temperature drift

Frequency response: Flat response from DC to 100 kHz

Environmental Specifications
Operating temperature: -10°C to +50°C

Storage temperature: -25°C to +70°C

Humidity: 85% RH or less (no condensation)

Altitude: 2000 m or below

Safety Features
Overcurrent protection: Built-in protection circuitry

Insulation resistance: 100 MΩ or more (500 V DC)

Dielectric strength: 3700 V AC (50/60 Hz) for 1 minute

Safety category: CAT III 600 V

Typical Applications
Precision current measurement with power analyzers

Motor efficiency testing

Power converter evaluation

Harmonic current measurement

Energy consumption analysis

Research and development projects

Quality control in manufacturing