IS 694 is the Indian Standard specification published by the Bureau of Indian Standards (BIS) for PVC insulated cables intended for working voltages up to and including 1100V. It is the foundational quality specification for the electrical house wires used in virtually every home, office, factory, and building in India.
The standard was first published decades ago and has gone through several revisions. The current edition reflects updated conductor purity requirements, insulation thickness specifications, and flame retardancy test procedures — incorporating learnings from both Indian field experience and international standards alignment.
Compliance with IS 694 is mandatory — not optional — for any PVC insulated wire sold for electrical installation purposes in India. BIS enforces this through its licensing scheme, which requires manufacturers to obtain a BIS licence before affixing the ISI mark on their products. The ISI mark is the consumer-visible symbol that indicates compliance with IS 694.
For engineers, specifiers, and procurement managers, understanding what IS 694 actually specifies — beyond just recognising the ISI mark — allows you to ask the right questions, verify compliance intelligently, and distinguish genuinely compliant products from those that merely appear compliant.
IS 694 covers a specific category of cables defined by their construction and voltage rating. It is important to understand what falls within this scope and what does not.
Within IS 694 scope:
Single core PVC insulated unsheathed cables (house wires) — the most common type for internal wiring
Single core PVC insulated sheathed cables (with an outer PVC jacket)
Multicore PVC insulated cables for internal wiring
Flexible cords and cables for appliance connections
Voltage ratings covered: 250V, 440V, 660V, and 1100V (designated as 250/440V, 450/750V, etc.)
Conductor cross-sections: typically 0.5 sq mm up to 16 sq mm for house wire applications
Outside IS 694 scope (covered by separate standards):
Armoured cables — covered by IS 1554 (PVC insulated) or IS 7098 (XLPE insulated)
Service cables and distribution cables above 1100V
Submersible pump cables — covered by IS 694 but with additional requirements under pump cable specifications
Control and instrumentation cables — separate specifications apply
The copper conductor at the centre of the cable is where IS 694 begins its quality requirements. The standard specifies:
Conductor material — electrolytic grade copper, minimum 99.9% purity. Lower purity copper has higher resistivity, reducing the effective current carrying capacity
Conductor classes — IS 694 recognises different conductor constructions: solid (Class 1), stranded (Class 2), and flexible stranded (Class 5 and Class 6) — the class determines how the individual wires within the conductor are arranged
Maximum DC resistance per km — this is the critical measurable parameter. For example, a 1.5 sq mm conductor must not exceed 13.3 ohms per km at 20°C. A conductor with more resistance contains less copper or lower-purity copper than specified
Dimensional tolerances — the actual conductor cross-section must not deviate from the nominal by more than the standard allows
The resistance test is the most revealing check for conductor quality. You can perform a simplified version yourself: measure the resistance of a known length of wire with a multimeter and compare against the IS 694 table values. A wire with conductor resistance significantly above the specified maximum is non-compliant — regardless of what is printed on its surface.
The PVC insulation surrounding the conductor is the second major area IS 694 regulates. The insulation must protect users from the live conductor and must withstand the rated voltage throughout the cable's service life.
IS 694 specifies:
PVC compound grade — the insulation must be made from an appropriate grade of PVC compound with the required electrical and mechanical properties
Minimum insulation thickness per cross-section — for example, a 1.5 sq mm cable at 750V rating requires a minimum nominal insulation thickness of 0.7 mm; the actual minimum (minimum of individual measurements) is specified separately
Voltage withstand test (High Voltage Test) — the finished cable is subjected to an AC high voltage (typically 2–3 kV) for a specified duration without insulation breakdown
Insulation resistance test — measures the resistance of the insulation to confirm it is high enough (typically millions of megaohms per km at 20°C)
FR grade requirement — for FR designation, the insulation must pass vertical flame propagation tests specified in the standard
Hot set test and mechanical properties — the PVC compound must not deform excessively at elevated temperatures
Thin insulation is a common shortcut in non-compliant cables. When insulation thickness is below the IS 694 minimum, it is more susceptible to physical damage during installation, may not pass voltage withstand tests, and degrades faster over the cable's lifetime.
Every metre of IS 694 compliant wire has mandatory information printed directly on the insulation surface. Understanding these markings allows you to verify basic compliance information at the point of purchase or on-site:
IS 694 — the standard number, confirming the cable is made to this specification
Manufacturer name or trademark — identifies who made the cable (cross-reference with BIS licence database)
Voltage rating — e.g., '750V' or '1100V' — the rated working voltage of the insulation
Conductor cross-section — e.g., '1.5' or '2.5' — nominal cross-sectional area in sq mm
ISI mark — the circular symbol with 'IS' inside, followed by the BIS licence number
Year of manufacture — typically the last two digits of the year, sometimes the full year
Conductor class — sometimes printed, identifies whether the conductor is solid (1), stranded (2), or flexible (5/6)
If a cable lacks the IS 694 marking, the ISI mark, or the manufacturer name printed clearly on the surface, treat it as suspect. Genuine IS 694 cables have consistent, clear, and legible markings printed at regular metre intervals along the entire cable length.
The Indian market unfortunately has a significant presence of non-compliant cables that are marketed without a genuine BIS licence. Here is how to practically distinguish compliant from non-compliant products:
Visual check — look for IS 694, the ISI mark, and BIS licence number printed on the cable surface. Non-IS cables often have vague or absent markings
Resistance test — measure conductor resistance with a multimeter over a known length (e.g., 10 metres); calculate and compare to IS 694 maximum. Higher than specified = non-compliant conductor
Weight check — IS 694 cables weigh more than non-compliant cables of the same cross-section because they contain more copper. 1 km of 2.5 sq mm conductor should weigh approximately 22 kg (copper weight alone)
Insulation burning test (field test) — carefully burn a short piece of cable in open air; FR wire should self-extinguish within 60 seconds of removing the flame. If it continues burning freely, it is likely non-FR or non-compliant
BIS licence verification — look up the licence number on the BIS website or BIS Care app to confirm it is valid and corresponds to the manufacturer on the cable
The resistance test and weight check are the most reliable field methods. Non-compliant cables that print IS 694 markings without actually meeting the standard are identified quickly by these two simple checks.
BIS provides several tools that allow anyone to independently verify whether a manufacturer holds a valid BIS licence for IS 694 cables:
BIS Care Mobile App — available on Android and iOS from official app stores; enter the licence number from the cable to see full licence details including validity, product scope, and manufacturer name
BIS website (bis.gov.in) — navigate to the 'Licence Details' or 'BIS Product' section and search by licence number or manufacturer name
Information available in the BIS database: licence number, manufacturer name and address, product scope (which IS standard and which product specifications are covered), licence validity date
If the licence number does not appear in the BIS database, or appears under a different company name than printed on the cable, the product is non-compliant — regardless of any marks on the cable
We encourage buyers, project managers, and site engineers to routinely check BIS licences for the wire products they are procuring. This simple check, which takes under a minute on the BIS Care app, is the most reliable way to confirm you are purchasing genuinely compliant material.
Elmeck Wires & Cables holds a valid BIS licence for the manufacture of PVC insulated cables under IS 694. Our BIS licence number is printed on every metre of cable we manufacture, and you can verify it independently at any time using the BIS Care app or the BIS website.
Our IS 694 compliance covers:
FR grade house wires in cross-sections from 1.0 sq mm to 16 sq mm
FRLS grade house wires in the same cross-section range
Both solid and stranded conductor constructions
Voltage ratings up to 1100V
The ISI stamp on an Elmeck cable is not decorative — it represents mandatory third-party laboratory testing of our conductor resistance, insulation thickness, voltage withstand, and flame retardancy, combined with periodic factory audits by BIS officers. Our manufacturing processes are maintained specifically to ensure every batch of wire we produce meets or exceeds IS 694 requirements.
For project authorities, government buyers, or institutional purchasers who require a copy of our BIS licence certificate for their compliance records, please contact us directly. We are happy to provide the documentation promptly. Reach us on WhatsApp at +91 93111 52255 or write to us through the contact form on our website.
