Rheostat, Constantine (Eureka) Wire

Product Code : LSK-EAE-11115

Rheostat, Constantine (Eureka) Wire (SKU LSK-EAE-11115) is a sliding-contact rheostat wound with constantan (Eureka) wire on a porcelain tube, used as a variable resistance or a potential divider in school and college electricity practicals. Science Lab Supplies makes it in its own works at Plot 448, HSIIDC Industrial Area, Saha, Ambala, India, and quotes it straight to schools, colleges, tender contractors and distributors.

Specifications

The full specification is listed in the table below. In short, layers of electrically oxidised constantan wire are wound on an insulated, heat-resistant porcelain tube between moulded supports, and a phosphor-bronze slider with a double contact runs on a guide rod, with three brass terminals and current ratings from 0.6 A to 8 A.

Applications and Experiments for the Constantan Wire Rheostat

The rheostat controls the current in a circuit or taps off part of a supply voltage, so students can take a series of readings without changing the source. As physics lab equipment in India it serves Ohm's law, potentiometer, meter bridge and characteristic-curve practicals from Class 10 to B.Sc. level.

• Class 10 and Class 11–12: varying the current through a resistor for Ohm's law, read on an Ammeter and a Voltmeter.
• Potentiometer and meter bridge work: setting the driving current through the bridge wire.
• Potential divider: using all three terminals to take a variable voltage from a fixed supply.
• B.Sc. and diploma labs: current control while calibrating meters or plotting component characteristics.

Standard Scope of Supply

Each rheostat comes as one assembled unit: the constantan winding on its porcelain tube, two moulded end supports, the guide rod with brass contact block and phosphor-bronze slider, and three brass terminals. State the resistance and current rating you need; leads and meters are quoted separately.

Packing, MOQ and Lead Time

Quotations can cover a single rheostat or a full set across several current ratings for a physics laboratory. Science Lab Supplies sets out packing, delivery time and price for that quantity on each quotation, and meters, keys or resistance boxes can be included on the same one.

Science Lab Supplies holds an Importer-Exporter Code and can ship to buyers in Uganda, the UAE, Saudi Arabia, Oman, the Philippines and Nepal. For a quote, use the contact page or the enquiry cart; institutional tenders are explained on the lab tender page.

Frequently Asked Questions

What current ratings are available?
Constantan-wound models run from 0.6 A to 8 A and come in a variety of resistance values. Give the resistance and maximum current of your circuit on the enquiry so the right model is quoted.

Can it be used as a potential divider?
Yes. One terminal connects to the sliding contact and the other two to the ends of the winding, so the rheostat works as a variable resistance or, using all three terminals, as a potential divider.

How does it differ from the nichrome rheostat?
The Rheostat Nichrome Wire Groove Type shares the porcelain tube and brass slider construction but is wound with nichrome wire and rated from 0.3 A to 6.5 A; this model uses constantan wire and covers 0.6 A to 8 A.

Is Science Lab Supplies the manufacturer or a trader?
Science Lab Supplies is the manufacturer: the rheostat is wound and assembled in its own factory at Saha, Ambala, India, and every quotation for it is issued directly by that factory.

Related Rheostats, Resistance Boxes and Keys

These items share circuits with a rheostat: they set fixed resistances, switch the current, or carry the bridge and potentiometer wire that a rheostat drives, and all of them can go on one quotation.

• Rheostat — 10 Ω high-power rheostat with 4 mm safety sockets, up to 5.7 A continuous.
• Resistance Box Electronic Type — 50, 100, 500 and 1000 ohm versions.
• Resistance Box Plug Type (Constantan / Manganin Coil) — coils on bakelite spools, in a wooden box.
• Meter Bridge or Wheatstone Bridge With Pencil Jockey — four-gap bridge with 24 SWG constantan wire.
• Potentiometer with Jockey Pencil — 100 cm wooden scale with brass blocks.
• Tapping Key Physics Lab — momentary key with two 4 mm brass binding posts, up to 2 A.
• SWG Manganin Wire (100g) Spoolm — bare manganin resistance wire on a 100 g spool.

Browse the full Electrical and Electronics range, the Lab Meters range for ammeters and voltmeters, or all physics lab equipment.

Last updated: 9 October 2026