Aluminium armoured cable current rating chart: 4 core sizes for contractors in Kishanganj, Purnea and Katihar

The current rating of a 4 core aluminium armoured cable depends on its size, its insulation (XLPE or PVC) and how it is laid. As a guide, one maker’s catalogue lists a 4 core 25 sq mm XLPE aluminium armoured cable at about 94 A in ground and 96 A in air, 95 sq mm at about 196 A and 221 A, and 300 sq mm at about 367 A and 455 A. Always check the rating sheet of the exact brand you buy, then apply derating for your site.

This guide is for electrical contractors, panel builders and project buyers working in Kishanganj, Purnea, Katihar and the rest of Seemanchal. The same advice applies across North Bengal, Bihar and Sikkim. Shree Shyam Suppliers supplies LT armoured cable in all common sizes, cut to length, with itemised quotes on WhatsApp.

What is the current rating of 4 core aluminium armoured cable?

The table below is taken from KEI’s published catalogue pages for 4 core aluminium XLPE armoured cable and 4 core aluminium PVC armoured cable. We read both pages today. The pages do not print the laying conditions next to the table, so treat these as catalogue reference figures, not design values. Other brands such as Havells, Polycab, Mescab and RR Kabel publish their own sheets, and the numbers differ a little from brand to brand.

Size (sq mm)	XLPE (A2XFY / A2XWY) in ground	XLPE in air	PVC (AYFY / AYWY) in ground	PVC in air
16	73 A	70 A	60 A	51 A
25	94 A	96 A	76 A	70 A
35	113 A	117 A	92 A	86 A
50	133 A	142 A	110 A	105 A
70	164 A	179 A	135 A	130 A
95	196 A	221 A	165 A	155 A
120	223 A	257 A	185 A	180 A
150	249 A	292 A	210 A	205 A
185	282 A	337 A	235 A	240 A
240	326 A	399 A	275 A	280 A
300	367 A	455 A	305 A	315 A

Source: KEI catalogue pages linked above, 4 core armoured aluminium cable. The PVC page also lists a lower “in duct” rating, for example 95 A for 50 sq mm and 140 A for 95 sq mm.

XLPE or PVC armoured cable: which one carries more current?

XLPE cable carries more current than PVC cable of the same size. You can see it in the table: a 95 sq mm XLPE cable is listed at 196 A in ground, the PVC one at 165 A. XLPE insulation can safely run hotter, so the same aluminium conductor can carry more load.

• A2XFY / A2XWY = aluminium, XLPE insulated, strip (F) or round wire (W) armoured, PVC outer sheath. Made to IS 7098 (Part 1).
• AYFY / AYWY = aluminium, PVC insulated, strip or wire armoured. Made to IS 1554 (Part 1).

For most new LT feeders today, contractors specify XLPE. PVC armoured cable is still used, mainly where a tender or an old drawing asks for it. If you want the full meaning of these codes, see our guide on armoured vs unarmoured cable.

Why is the rating in ground different from the rating in air?

Heat. A cable gets warm when it carries current, and the rating is simply how much current it can carry before it gets too hot. In air, heat escapes into the air around the cable. In ground, heat has to pass through soil, and how well that happens depends on the soil, its moisture, the depth and how many cables are laid together.

That is why the in-air rating is higher for most sizes, and why a cable pulled through a buried pipe (duct) gets the lowest rating of all.

How do I find the right cable size for my load in kW or amps?

This is the question we get most often from contractors. The steps below are general trade practice, not a substitute for the design engineer’s calculation.

1. Work out the full-load current. For a 3-phase, 415 V load: current (A) ≈ kW × 1000 ÷ (1.732 × 415 × power factor). A 50 kW load at 0.8 power factor draws about 87 A.
2. Apply derating. Reduce the catalogue rating for high ambient temperature, cables laid in groups, cables in pipe or duct, and laying depth. The maker’s catalogue gives the correction factors. In grouped trenches the drop can be large.
3. Check voltage drop on long runs. On a long feeder to a pump house, cold storage, rice mill or farm in rural Purnea or Araria, voltage drop often decides the size, not current. A cable that is fine on current may still need to go one size up.
4. Match the breaker. The MCB or MCCB rating must not be more than the cable’s derated rating. See our guide on MCB, RCCB, RCBO and MCCB.

Full-load current (after your calculation)	Usual starting point to check (XLPE Al armoured, 4 core)
Up to about 60 A	16 or 25 sq mm
About 60–100 A	25 or 35 sq mm
About 100–150 A	50 or 70 sq mm
About 150–220 A	95 or 120 sq mm
About 220–300 A	150 or 185 sq mm
Above 300 A	240 or 300 sq mm, or two runs in parallel

This second table is general practice only, a starting point before derating and voltage drop are checked. Ask your consultant or our counter team to check your actual run length and laying method.

Aluminium or copper armoured cable for a feeder?

For main feeders above about 16 sq mm, aluminium armoured cable is the usual choice in India because it is much lighter and costs less per metre for the same job. Copper carries more current for the same size, so as general practice aluminium usually needs a bigger size than copper for the same load. Copper armoured cable is common for small sizes, control cabling and where space at the panel is tight.

If you use aluminium cable on copper busbars or MCCB terminals, use bimetallic lugs. Our cable gland and lug guide explains how to pick glands by the cable’s outer diameter, which is also listed on the KEI pages above.

Laying armoured cable in Seemanchal: what to watch on site

• Wet and low-lying ground. Much of the land around Kishanganj, Purnea, Katihar and Forbesganj stays wet through the monsoon. Wet ground can help cooling, but water at joints and terminations is the real risk. Use proper sealed joints and double compression glands outdoors.
• Long rural runs. Low voltage at the far end is a common complaint. Check voltage drop before finalising the size.
• Mixed sizes in one trench. Group derating applies. Do not size each cable as if it were laid alone.
• Earthing. Earth the armour at the gland. Never rely on armour alone where a separate earth conductor is specified, and keep earth pits tested as per IS 3043.

Always get the cable laid, terminated and tested by a licensed electrician or electrical contractor.

What should I write in the BOQ for armoured cable?

A clear BOQ line saves confusion and gets you a correct quote the first time.

BOQ item	Example
Voltage grade	1.1 kV
Conductor	Aluminium, stranded
Insulation	XLPE (IS 7098 Part 1) or PVC (IS 1554 Part 1)
Cores and size	4 core × 95 sq mm (or 3.5 core if specified)
Armour	Galvanised steel strip (A2XFY) or round wire (A2XWY)
Brand / approved makes	e.g. Havells, Polycab, KEI, Mescab, RR Kabel
Length	Total metres, plus cut lengths if needed
Accessories	Double compression glands, aluminium or bimetallic lugs, jointing kits
Documents	Test certificate, invoice with HSN and GST

Why buy armoured cable from a local authorised dealer?

Shree Shyam Suppliers is an authorised dealer for Havells, Lauritz Knudsen (L&T) and Mescab, and also deals in Polycab, KEI and RR Kabel. Buying locally means genuine, ISI-marked cable, help choosing the size, cable cut to the lengths you need instead of buying a full drum, and glands, lugs, MCCBs and panels from one place. We deliver across North Bengal, West Bengal, Sikkim and Bihar. We never quote rates in a blog because aluminium prices move often; WhatsApp us for today’s rate. Browse our cables and wires range.

Ordering tip

Send us on WhatsApp: cable type (XLPE or PVC, strip or wire armour), cores and sq mm, total metres and any cut lengths, preferred brand, the glands and lugs you need, and your site location. We will send an itemised quote with today’s rate.