A Voltage Transformer (VT) is a device which converts energy of one form to another. VT’s are used to monitor alternating AC or DC current by measuring voltage directly or through a VT. Voltage Transformers are a parallel connected type of instrument transformer. They are designed to present negligible load to the supply being measured. They have an accurate voltage ratio and phase relationship to enable accurate secondary connected metering.
There are two basic solutions within Voltage Transformers – A potential transformer (PT) has an iron-core construction. A capacitor coupling voltage transformers (CVTs) lowers the voltage level first and then use the iron-core transformer to get further reduction in voltage by using a capacitor coupling principle. The two of these transformer types are usually free-standing.
The potential transformer is often used to measure the voltages at substation busses. However the CVTs can be used for the same measurement purposes on transmission lines individually. The transformers are used to bring the voltages down to an acceptable level used by protective relays because the power systems voltage levels range well above kilovolt values.
Types of Voltage Transformer
- Electromagnetic – The electromagnetic potential transformer is a wire-wound transformer.
- Capacitor – Voltage transformers (CVT) use a capacitance potential divider using higher voltages due to lower costs than an electromagnetic VT’s.
- Optical – An optical voltage transformers make use of the Faraday effect which rotates polarised light in optical materials.
DC Voltage Transformers
The DVT-1000 DC Voltage Transformer is designed to convert a 10-1000 DC Voltage input to either a 4-20mA output or a voltage standard output that is proportional to the input. It is also perfect for solar-string voltage monitoring. The DC Voltage transformer provides effective and safe isolation between the input and output.
For Bulk Orders of the DVT-1000 DC Voltage Transducer inquire by phone or email.
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- Primary voltage DVT-100: 1000-10,000 Vdc
- Output 4-20mA, 0-1Vdc, 0-5Vdc
- Accuracy: 1% over range
- Linearity: 0.5% over range
- Response time: 10.0 mSec
- Working Range: 0-120%
- Overload: 150% continuous
- Temperature: -30 degrees C to 70 degrees C operating
- Humidity: 90% operating
- Isolution: 4.5KV, 1 Minute
- Supply voltage: 15-48 Vdc
The Voltage Sensor is typically described by its voltage ratio from primary to secondary. Meaning a 500:120 PT provides an output voltage of 120 volts when 500 volts are input across its primary winding. We are a trusted supplier of Magnelab Voltage Transformers. See our VT range here.
The VT is seen as an electrical component instead of an electronic component. A transformer is a very simple static electro-magnetic passive electrical device that works by converting electrical energy from one value to another.