Reversing Key Manufacturer,Supplier and Exporter in India
Product Code : EL-SLE-4713
Jlab Export is a leading Reversing Key Manufacturer,and suppliers in India
Reversing Key (code EL-SLE-4713) is a circuit key that reverses the direction of current in a circuit, used in physics lab experiments where readings are taken with the current flowing first one way and then the other. Four gun-metal segments are mounted on its Bakelite base. It is made by Jain Laboratory Instruments Pvt Ltd (JLab) at its works in Ambala, India.
Specifications
| Parameter | Detail |
|---|---|
| Function | Reverses the direction of current in the circuit |
| Contacts | Four segments of gun metal (a copper alloy) |
| Base | Bakelite |
| Use | Physics lab experiments |
| Quality check | Each reversing key is visually inspected before dispatch |
| Pack quantity | Each (sold individually) |
| Minimum order quantity | 10 units |
| Dispatch time | Usually 7–10 working days |
| Product code | EL-SLE-4713 |
| Manufacturer | Jain Laboratory Instruments Pvt Ltd (JLab) — OEM |
| Country of origin | India (made in Ambala, Haryana) |
How Does It Compare with Other JLab Circuit Keys?
| Model | What it does | Listed construction |
|---|---|---|
| This key (EL-SLE-4713) | Reverses the current direction | Four gun-metal segments on a Bakelite base |
| Plug Key | Makes and breaks the circuit | Terminals on a Bakelite base; tapered plug fits into brass blocks |
| One Way Key | Makes and breaks one circuit | Brass blocks with 4 mm terminals on a moulded plastic base; tapered brass plugs with fluted plastic tops |
| Two Way Key | Switches between two circuits | Same block-and-plug construction in a two-way layout |
Use the reversing key whenever an experiment needs the current turned round without rewiring; a plug key or one-way key simply switches the circuit on and off, and a two-way key selects between two paths.
What Is the Reversing Key Used For?
Its classic use is with a tangent galvanometer or a circular coil on a deflection magnetometer. Students note the compass deflection, reverse the current with the key, note the deflection on the other side and take the mean; averaging the two cancels the error caused when the coil is not set exactly in the magnetic meridian. The same key is used to reverse the field of an electromagnet or solenoid, to show that a compass needle or a current-carrying conductor turns the other way when the current is reversed, and in college electrical labs wherever polarity must be switched quickly.
Switch the current off or keep it small while operating the key, keep the gun-metal contacts clean and dry so they do not add resistance, and tighten connecting leads firmly on the terminals.
What to Specify When Ordering
- Quantity — minimum 10 units; one per bench for tangent galvanometer practicals.
- Terminal style — tell JLab if your leads use a particular connector, so it can confirm the key will take them.
- Other keys and meters — plug keys, galvanometers and connecting leads can be added to the same quotation.
Frequently Asked Questions
What does a reversing key do?
It reverses the direction of the current in the part of the circuit connected to it, without changing any wires.
What is it made of?
Four gun-metal segments mounted on a Bakelite base. Gun metal is a copper alloy, and Bakelite insulates the segments from one another.
Why reverse the current in a tangent galvanometer experiment?
Reading the deflection with the current in both directions and averaging the readings cancels errors from imperfect alignment of the coil, giving a more reliable result.
How is it different from a plug key?
A plug key only makes or breaks a circuit. The reversing key also changes the direction of the current, which a plug key cannot do.
Who manufactures the reversing key?
Jain Laboratory Instruments Pvt Ltd (JLab), at its own works in Ambala, Haryana, India.
OEM Manufacturer
JLab is the trading name of Jain Laboratory Instruments Pvt Ltd, a manufacturer of electricity and magnetism apparatus and other physics lab equipment in India, incorporated in 2017 and based on Hargolal Road, Ambala, Haryana. Reversing keys are built in JLab’s own works rather than bought in, so schools, colleges, dealers and importers deal with the maker directly, each key is visually inspected before dispatch, and repeat orders come from the same works. JLab exports worldwide and ships to buyers in every region — Tajikistan in Central Asia, Saudi Arabia in the Middle East, Zimbabwe in East Africa, Slovenia in Southern Europe and Lesotho in Southern Africa are a few examples.
Apparatus Used with the Reversing Key
- Tangent Galvanometer — Bakelite coil with a rotating magnetometer, the main instrument the key is used with.
- Galvanometer — a sensitive current detector for electricity practicals.
- Ammeter — desk-stand meter for setting and reading the current.
- Connecting Leads — plastic-covered leads with connectors.
Find more in the School Lab Equipment range.
Request a Quote
Ask the manufacturer for a quotation: use the Add To Cart enquiry button, or send the quantity (minimum 10 units), any keys, meters or leads to include and the delivery location through the contact page.
Last updated: 4 October 2026
