The DC smoothing reactor sits on the rectifier bus of the medium-frequency power supply. It smooths the direct current and limits how fast current rises if the inverter sees a short circuit.
Technical Data
| Item | Catalog value |
|---|---|
| Place in the circuit | DC bus between the rectifier and the inverter |
| First duty | Smooths the rectifier current |
| Second duty | Limits current rise if the inverter sees a short circuit |
| US harmonic standard | IEEE 519, together with 6, 12 or 24 pulse rectification |
| Rectifier | 5th | 7th | 11th | 13th | 17th | 19th | 23rd | 25th |
|---|---|---|---|---|---|---|---|---|
| 6 pulse | 0.175 | 0.11 | 0.045 | 0.029 | 0.015 | 0.01 | 0.009 | 0.008 |
| 12 pulse | — | — | 0.007 | 0.004 | 0.002 | 0.001 | 0.0009 | 0.0008 |
| 24 pulse | — | — | — | — | — | — | 0.0006 | 0.0005 |
| US standard | Applies to |
|---|---|
| IEEE 519 | Harmonic current limits, matched to 6 / 12 / 24 pulse rectifiers |
| NFPA 70 (NEC) | Incoming voltage, grounding and disconnect |
| UL 508A | Control cabinet construction |
| NEMA 250 | Enclosure type for the power cabinets |
| NEMA MG 1 | Cooling-fan and pump motors |
Every figure in these tables is taken from the factory sheets in the product folder and is written in English. 1 metric ton = 1.102 US short tons. Power-supply ratings can still be negotiated to the customer requirement, as the sheet itself states. American standards are the US specifications normally requested with this equipment.
Key features
- Sized for the supply power, not taken from a generic catalog item
- Limits di/dt during an inverter shoot-through
- Core and air gap designed for the rectifier pulse count
- Poor reactor design shows up as supply trips and high harmonics
Construction
- Iron core or air-gapped core, copper or aluminum winding, and terminals into the DC bus.
Working principle
After the rectifier, the reactor keeps the current continuous for the inverter and absorbs the energy of a fault long enough for protection to open.
Applications
Steel, cast iron, stainless steel, copper, aluminum, aluminum alloy, brass and other non-ferrous metals.
Complete system integration
This equipment sits in the same line as the power supply, the capacitor bank, the induction coil, the magnetic yoke, the furnace body and the cooling system. A quotation can cover one item or the full line.
Customization
Capacity, voltage, frequency, dimensions and connection layout can be made to the furnace design. Send the drawing or the duty data below.
Catalog sheets
Questions before a quotation
Can the rating be customized?
Yes. Capacity, voltage, frequency, tube size and connection layout follow the furnace drawing and the metal.
What do you need for a quotation?
Furnace capacity, metal, melting temperature, melting rate, working hours, input voltage, frequency if known, tilting method and cooling-water conditions. A drawing helps.
Do you supply a single machine or the complete system?
Both. A spare coil, yoke, capacitor or cooling tower can be quoted alone. A new foundry line is quoted as a complete system.
Which metals can be melted?
Steel, cast iron, stainless steel, copper, aluminum, aluminum alloy, brass and other non-ferrous metals. The lining and the frequency follow the alloy.
Will you confirm the catalog numbers before manufacture?
Yes. The sheets on this page are the factory catalog for selection. The quotation states the rating that will be built.