Industry Outlook
IS 7098, is an Indian Standard, which has three parts, which are applicable on crosslinked polyethylene insulated PVC sheathed cables that are widely used in net power systems and power distribution and transmitting.
The usage of cables under mentioned Indian standards plays a crucial role in power distribution and transmission, which is essential for any economy, not just India. Considering the important role of crosslinked polyethylene insulated PVC sheathed cables, BIS (Bureau of Indian Standards) introduced IS 7098 in 1998 with the view of ensuring quality assurance.
And in order to achieve quality assurance, certain specifications have been provided in different parts of IS 7098, which have been revised at distinct times.
Here, IS 7098 Part 1 includes specifications for crosslinked polyethylene insulated PVC sheathed cables for working voltages up to and including 1100V. While IS 7098 Part 2 includes specifications for working voltages from 3.3kV up to and including 33 kV. Lastly, IS 7098 includes specifications for working voltages from 66 kV up to and including 220 kV.
Moreover, to ensure the manufacturing or importing of high-quality products, particular tests need to be conducted to ensure that a product meets the provided specifications.
Basically, the mentioned standard includes the information regarding the test to be conducted on the electrical cables to check their quality and credibility to reflect that certain technical standards have been followed. Product testing is crucial to ensure that a product is safe and reliable, which is important to stay ahead of the competition and maximize its reputation and profits.
Above all, product testing helps you retain the consumers by meeting their expectations.
For a better understanding of why product testing is important, let’s have a look at why product testing is crucial.
Why is Product Testing Crucial | Importance of Product Testing
- One of the most important purposes of testing is the quality assurance of a product that reflects high quality, safety, and reliability.
- Product testing allows the manufacturer to ensure conformance with established technical standards to produce high-quality and safe products.
- Build reputation and maximize the profit, considering that a tested product indicates quality assurance.
- Helps in retaining customers, thus, providing a competitive edge.
- Helps in understanding distinct types of stress a product can endure, be it in case of weather, wear tear, and other conditions.
- In the initial prototyping stage, if you are trying to avail investment in order to manufacture your product in mass quantities, a tested product can allow you to achieve patent and investors as it shows the quality and functionality of the product.
With the benefits of product testing, we can clearly estimate how testing ensures quality assurance and product credibility. For a better understanding, let’s have a look at its an example,
Through product testing, it can be easily proved that electrical cables are safe to use, however, in case of any defects, it will be found during product testing.
Since, it has been established how essential product testing is, now let’s move to the benefits of complying with standards.
What Are the Benefits of Complying With Standards?
A BIS certificate offers numerous benefits to manufacturers and importers of the product, which further helps in building trustworthiness and reliability, thus retaining the customers.
Why, don’t we look at other benefits of the same –
- A certified product acts as a shield against penalties and fines which could be imposed for not certifying a product.
- A certified product serves as evidence that a product has been tested and certified as per prescribed standards.
- A certified product provides a sense of security and safety to the consumers, thus ensuring easy acceptance.
- It provides a competitive advantage over competitors.
- Easy market acceptance as a product is tested and certified.
- Confirm the unmatched quality standards.
- Seamless to file government tenders.
With these benefits of ensuring conformance with IS 7098 standards and specifications, a manufacturer can establish that a product is safe, reliable, and credible, thus, confirming unmatched quality standards.
Now, in the next section, we will learn about test requirements and product scope under each part of the IS 7098.
Product Scope of IS 7098 Part 1
IS 7098 Part 1 includes cables of both armored and unarmoured single, twin, three, four, and multi-core crosslinked polyethylene (XLPE) insulated and PVC sheathed cables for electric supply and control purposes.
Moreover, the cables covered under Part 1 of IS 7098, are appropriate to use on AC single-phase or three-phase (earthed or unearthed) systems for rated voltages up to and including 1100 V. These cables may be used on DC systems for rated voltages up to and including 1500 V to earth.
It is to be noted that Armored cables mentioned in the IS 7098 are appropriate to use in mines also. Though, for such cables, additional requirements must be met, wherever necessary.
The mentioned cables are ideal to use where a combination of ambient temperature and temperature increases because of load results in a conductor temperature not exceeding 90�C under normal operation and 250�C under short circuit conditions.
Refer to the below-mentioned table for understanding the classification of cables for improved fire performance.
| Category | Environment description | Cables definition |
|---|---|---|
| 01 | Cables in open areas | Flame retarded, single cablesself-extinguisbing does not propagate flame |
| C1 | Cables in constraints areas | Flame retardant does not propagate fire even when installed in groups in vertical ducts |
| C2 | Cables in constraints areas with restricted human activities and/ or presence of sophisticated systems | Flame retardant cables with reduced areas with reduced halogen evolution and smoke |
Since we have established a brief understanding of product scope, let’s move on to test requirements under the same.
Properties of XLPE Insulation
| S. no | Property | Test requirement |
|---|---|---|
| 1 | Tensile strength | 12·5 N/mml , Min |
| 2 | Elongation at break | 200 percent,Min |
| 3 | Aleina in air ovenTreatment: Temperature DurationTensile strength variationElongation variation | 13S±3"C7 days±25 percent,Max ±25 percent,Max |
| 4 | Hot setTreatment: Temperature Time under load Mechanical stressElongation under loadPermanent elongation (set) after cooling | 200±3-degree celsius 15 minutes20N/ cm3 175 percent, Max15 percent, Max |
| 5 | Shrinkage Treatment: Treatment DurationWater absorbed | 85±2- degree celsius 14 days1 mg/ cm3, Max |
| 6 | Volume resistivity At 27°Cat 90°C | 1 X 101t ohm-em, MinI x 10" obm-cm, Min |
Product Scope of IS 7098 Part 2
IS 7098 Part 2 covers the product’s requirements or specifications for crosslinked polyethylene insulated and PVC sheathed or polyethylene sheathed cables for single-phase or three-phase (earthed or unearthed) systems for electricity supply purposes. It includes four distinct types of cables as mentioned below –
- Single-core unscreened, unarmoured cables, however, non-magnetic metallic tape covered.
- Single-core screened unarmoured cables.
- Single-core armored (non-magnetic) screened or unscreened cables.
- Three-core armored screened or unscreened cables.
The mentioned cables are ideal for use where the sum of ambient temperature and temperature rise because of load results in a conductor temperature not exceeding 90°C under normal operation and 250°C under short-circuit conditions.
Moreover, armored cables up to 11 kV grade are appropriate to use for the purpose of mining, although certain additional requirements need to be met, whenever required. Similar to IS 7098 Part 1, this standard also includes cables with improved fire performance categories, that is C1 and C2 and for cables, additional requirements have been provided.
To attain the specification mentioned in the standards below mentioned tests will be conducted on the product for quality assurance –
- Routine test
A routine test is a test conducted by the manufacturer applies to the finished length of cables, to demonstrate the integrity of the cable.
- Type test
A test conducted prior to the supply of the product for general commercial purposes to demonstrate satisfactory performance characteristics.
- Acceptance test
Acceptance tests will be performed on product samples with the motive to accept a lot.
- Optional test
Under the optional test, a special test will be performed as required in accordance with the agreement between supplier and purchaser.
Properties of XLPE Insulation
With the understanding of the first two parts of IS 7098, let’s finally move to IS 7098 Part 3.
Product Scope IS 7098 Part 3
Part 3 of IS 7098 includes requirements or specifications for single-core, cross-linked polyethylene insulated, unarmoured, or armored (with or without lead alloy sheath) and thermoplastic outer sheathed cables for 3 phase ac earthed system for electric supply.
Cables under Part 3 of IS 7098, distinct voltage, as mentioned in the below-mentioned table –
| System Voltage U (kV) | Rated Voltage Uo/U (kV) | Highest System Voltage Um (kV) |
|---|---|---|
| (1) | (2) | (3) |
| 66 | 38/66 | 72.5 |
| 110 | 64/110 | 123 |
| 132 | 76/132 | 145 |
| 220 | 127/220 | 245 |
Moreover, cables under Part 3 of IS 7098 are ideal for use where the combined ambient temperature and temperature rise due to load results in a conductor temperature not exceeding 90°C under normal operation and 250°C under short circuit operation.
To attain the specification mentioned in the standards below mentioned tests will be conducted on the product for quality assurance –
- Routine test
A routine test is a test conducted by the manufacturer applicable on the finished length of cables, to demonstrate the integrity of the cable.
- Type test
A test conducted prior to the supply of the product for general commercial purposes to demonstrate satisfactory performance characteristics.
- Acceptance test
Acceptance tests will be performed on product samples with the motive to accept a lot.
- Optional test
Under the optional test, a special test will be performed as required in accordance with the agreement between supplier and purchaser.
