Portable Wheatstone Bridge with Loop Test Manufacturer,Supplier and Exporter in India

Product Code : EL-SI-8040
Jlab Export is a leading Portable Wheatstone Bridge with Loop Test Manufacturer,and suppliers in India

Portable Wheatstone Bridge with Loop Test (code EL-SI-8040) is a portable bridge that measures resistance and, through a special switching arrangement, also carries out Murray loop, Varley loop and conductance tests for locating faults in cables. It is used in electrical engineering, diploma and cable-maintenance training labs, where students learn both ordinary bridge measurement and fault location on one instrument. It is made by Jain Laboratory Instruments Pvt Ltd (JLab) at its works in Ambala, India.

Specifications

How Does It Compare with the Standard Portable Wheatstone Bridge?

The two bridges share the same series arm, battery, galvanometer and push buttons. Pick the loop test version when cable fault location is part of the syllabus or the job; the standard bridge is enough for resistance measurement alone.

What Is the Loop Test Bridge Used For?

When an underground or long cable develops an earth fault or a short between cores, the fault can be located without digging along the whole route by loop tests. In a Murray loop test the faulty core is joined at the far end to a sound core of the same cable to form a loop, the loop becomes two arms of a Wheatstone bridge, and the balance gives the ratio of the distances to the fault. The Varley loop test uses the same loop with an adjustable resistance in one arm and also allows the loop resistance to be measured. This bridge provides both tests through its switching arrangement, plus the extra Murray loop factors, so students in power systems and cable labs can practise on a test cable panel and technicians can use it for training on real fault location.

For ordinary resistance work the bridge is used like any portable Wheatstone bridge: set the multiplier, adjust the decades until the galvanometer shows no deflection, and multiply. Keep the connecting leads short and clean when locating faults, because lead resistance adds to the loop, and press the battery button before the galvanometer button.

What to Specify When Ordering

• Model — this loop test bridge or the standard Portable Wheatstone Bridge.
• Quantity — the minimum order is 10 units.
• Accessories — list any connecting leads or other items you want quoted with the bridge.

Frequently Asked Questions

What tests can this bridge perform?
Resistance measurement, the Murray loop test, the Varley loop test and conductance tests, selected through a special switching arrangement.

What multiplying factors are provided?
Seven factors from ×1000 down to ×0.001 for resistance measurement and the Varley loop test, plus three additional factors of 10M, 100M and 1000M for Murray loop tests.

What is the difference between the Murray and Varley loop tests?
Both locate a cable fault by making the faulty and a sound conductor into a loop that forms part of a bridge. The Murray loop finds the fault position from the balance ratio alone, while the Varley loop adds an adjustable resistance and also gives the loop resistance.

Is it the same as the standard portable Wheatstone bridge?
It is the same except for the added Murray and Varley loop test facility; the series arm, battery, galvanometer and push buttons are listed as identical.

Who manufactures this bridge?
JLab (Jain Laboratory Instruments Pvt Ltd) builds it at its works in Ambala, Haryana, India, and supplies it directly.

OEM Manufacturer

JLab is the trading name of Jain Laboratory Instruments Pvt Ltd, a manufacturer of electrical measurement and physics lab instruments in India, incorporated in 2017 and based on Hargolal Road, Ambala, Haryana. This bridge is built at JLab’s own works, not traded, so engineering colleges, polytechnics, training centres, dealers and importers deal directly with the maker, each unit is visually inspected before dispatch, and follow-up orders are handled by the manufacturer. JLab is registered under CIN U29309HR2017PTC069123 and carries MSME Udyam registration UDYAM-HR-01-0003849 as a manufacturing enterprise. JLab exports worldwide and ships to buyers in every region — for example Eswatini in Southern Africa, Bangladesh in South Asia, Argentina in South America, Burkina Faso in West Africa and Kyrgyzstan in Central Asia. See the JLab lab tenders page for tender purchases.

Related Bridges and Resistance Boxes

• Portable Wheatstone Bridge — the standard model with built-in galvanometer and dry battery, for resistance measurement only.
• Industrial Double Bridge — double bridge for very low resistances in testing rooms, cable works and engineering labs.
• Double Portable Bridge — portable Kelvin bridge for measuring low resistances.
• Resistance Substitution Box — rotary-switch selection of resistances in steps, with socket connections.
• High Meg Resistance Box — decade box in the megohm range for high-resistance work.

Browse the complete Scientific Instrument range or all Indian Instruments.

Request a Quote

Quotes come direct from the manufacturer. Use the Add To Cart enquiry button on this page, or send the quantity (minimum 10 units), whether you need the loop test or standard model, and your delivery location through the contact page.

Last updated: 8 October 2026