Current transformer cores for 20/40 A energy meters

30 January 2002 Passive Components

Electronic energy meters are worldwide more and more specified according to the international standard IEC 1036, or derived national standards. This means, they have to resist unipolar alternating currents including a DC portion without core saturation. Here, current transformers (CTs) containing traditional core materials are not suitable.

In preference to usual solutions, which mostly have technical drawbacks or are too expensive, Vacuumschmelze has designed CTs that use Vitrovac amorphous cores. For meters designed for 60, 100 or 120 A maximum current, the core types W639, W588 and W774 are an industry standard. For 20 and 40 A meters, VAC now offers two new cores: W592 (20 A) and W800 (40 A).

Also available are completely wound and cased CTs. According to the manufacturer, Vitrovac CTs fulfil all requirements easily: the amplitude-error is extremely low; phase angle error typically lies around 4° and is very constant, so that it can be compensated easily; the temperature dependence of all properties is also very small. Furthermore, Vitrovac cores require less space, compared to other materials and they offer a lower sensitivity against external fields.

Avnet Kopp, (011) 444 2333

[email protected]

www.avnet.co.za

Further reading:

Cutting-edge hybrid capacitors
Avnet Silica Passive Components
Panasonic Industry recently announced the launch of the ZVU Series Hybrid Capacitors, a cutting-edge solution tailored to meet the escalating demands of advanced electronic systems.

Read more...

---

Low-profile tantalum chip capacitors
Electrocomp Passive Components
These general-purpose tantalum capacitors from Kyocera AVX are available in multiple case sizes with low profile options.

Read more...

---

Coupled inductor for high-performance applications
Passive Components
This coil with MnZn core is characterised by its high permeability and extremely low RDC values, which achieves excellent power density and very high efficiency.

Read more...

---

Power inductors
iCorp Technologies Passive Components
he HTF-MP series is more suitable for complex multiphase power supply applications in design, effectively meeting the needs of ultra-thin and high-power devices.

Read more...

---

SMT power inductors
Future Electronics Passive Components
The Würth Elektronik WE-MXGI SMT power inductors are the latest addition to Würth Elektronik’s moulded power inductor series, engineered for high-frequency power applications.

Read more...

---

Large capacitance MLCCs at 100 V
RS South Africa Passive Components
TDK Corporation has expanded its CGA series for automotive multilayer ceramic capacitors to 10 µF at 100 V in 3225 size.

Read more...

---

Film and mica capacitors
Actum Passive Components
By utilising various polymer dielectrics plastics, Exxelia film and mica capacitors meet most technical requirements and serve all functions from standard filtering to specialised applications.

Read more...

---

Power-over-coax inductors
RS South Africa Passive Components
TDK has expanded the ADL3225VF series of wire-wound inductors for automotive power-over-coax (PoC).

Read more...

---

Thick film power resistors
Electrocomp Passive Components
Vishay has released a new product to the market, its thick film power resistor, which is offered in a clip-mount TO-247 package.

Read more...

---

Compact EMI suppression capacitors
RS South Africa Passive Components
These new components from TDK are 20% smaller than previous models and meet Grade III Test B standards for temperature, humidity, and bias.

Read more...

---