TV31B02 2mA/2mA Voltage Transformer.

MINIATURE VOLTAGE TRANSFORMERS Current Type Voltage Transformers.

The YUANXING TV series of miniature voltage transformers are designed for applications where AC voltage signals must be transformed accurately into a lower voltage signal appropriate for micro-processor based circuits.

FEATURES :

• Low cost
• More than 10 standard sizes
• PCB mounting pattern

APPLICATIONS :

• 2mA/2mA transformer 
• For applications that require a limited internal space of devices
• Applications would include voltage, power and energy monitoring devices

SPECIFICATIONS :

• Exterior Material: ABS or PBT Resin UL flame retardant rating 94-V0
• Interior Insulation: Epoxy Encapsulated
• Isolation Voltage: 2500 Vrms for 1 minute
• Dielectric Resistance: 1000M Ohms @500 Vdc
• Surge Withstand: 5000V（1.2/50μs standard shock wave）optional
• Accuracy Class: as defined in IEC 60044-1 Part 1 Current
• Transformers Class 0.1，0.2；the linearity class 0.1L
• Operating Temperature: -25 to +55ºC,-40 to +85ºC Optional
• Frequency: 50 to 400 Hz
• RoHS compliant

APPLICATION METHOD :

The TV31 series current type voltage transformer is actually a current transformer with ratio 1:1. For application, the line voltage should not be directly put on to the transformer, it needs to connect a limiting resistor R’ in series with the transformer to transfer the voltage signal to mA current signal (recommended 2mA/2mA application).

For example: The measured voltage is 380Vac, then the R’ should be 190K ohms to limit the primary current of TV31 to 2mA. The secondary mA current output can be transferred to voltage signal by an operational amplifier I/V conversion circuit as figure 1. The advantage of this application is almost zero load state of TV31, with high accuracy and good linearity.

Application figure 2, directly connect a sampling resistor in parallel with TV31B02 secondary output to get the voltage signal. There is a maximum

sampling resistor value for different current type voltage transformer, please note for application to avoid the saturation of transformer and the distortion of output wave.