An IP rating tells you how well something resists dust and water. On an EV charging cable it is one of the specs worth checking, because the cable lives outdoors, gets dropped on wet ground and spends its life being plugged and unplugged in British weather.
This guide explains what the numbers mean, and, more usefully, what rating a charging cable actually needs. A lot of the IP advice online quotes figures meant for wall-mounted charge points, which is a different piece of equipment with a different job.
| Rating | First number, SOLIDS | Second number, LIQUIDS |
| IP44 | Protected against solid objects over 1mm, e.g. wires & nails. | Protected against water splashed from all directions, limited ingress permitted. |
| IP54 | Protected against dust, limited ingress, no harmful deposits. | Protected against water splashed from all directions, limited ingress permitted. |
| IP55 | Protected against dust, limited ingress, no harmful deposits. | Protected against low pressure jets of water from all directions, limited ingress permitted. |
| IP65 | Totally protected against dust. | Protected against low pressure jets of water from all directions, limited ingress permitted. |
| IP66 | Totally protected against dust. | Protected against strong jets of water, e.g. on a ship's deck, limited ingress permitted. |
| IP67 | Totally protected against dust. | Protected against temporary immersion in water. |
What IP rating does an EV charging cable actually need?
The standards that govern EV charging couplers, IEC 62196 and IEC 61851-1, require a Type 2 connector to reach IP44 in the mated condition, meaning while it is plugged into the car or the charge point. Unmated and without a cap, the requirement drops to IP24.
That is the bar a Type 2 cable has to clear. Our Type 2 to Type 2 charging cables are IP55 rated, which is comfortably above it, and our Type 2 to 3 pin cables are IP67 rated.
The reason those two numbers differ is worth understanding, because it explains the whole subject better than a league table of ratings does.
Why a cable and a charge point need different ratings
A wall-mounted charge point is fixed outdoors permanently. It faces driving rain on the same face of the box, year round, for a decade. That is why charge point manufacturers quote IP65 and IP66, and why those figures are the right ones for that product.
A charging cable is a different case. Its connectors are sealed against the car and the charge point while charging, which is when the electricity is actually flowing. The rest of the time it is coiled in a boot or hung on a wall holder, not bolted to a wall in the weather.
So the IP66 figure you will see quoted around the internet is a charge point number that has been copied onto cables. It is not the requirement for a coupler, and a cable that does not carry it is not unsuitable for outdoor use.
Why our 3 pin cables are rated higher
Our Type 2 to 3 pin cables are IP67 because they do a harder job than a Type 2 to Type 2 cable.
A 3 pin cable plugs into a domestic socket, often an outdoor one, and it carries an in-line control box that frequently ends up resting on the ground. Ground is where puddles are. IP67 covers temporary immersion, which is the realistic worst case for a box that sits on a wet driveway for twelve hours overnight.
A Type 2 to Type 2 cable has no control box and both ends are latched into sealed sockets while it works. It does not face the same risk, so it does not need the same rating.
What the two digits mean
The Ingress Protection rating has three parts: the IP mark, a first digit and a second digit. In IP67, “IP” is the mark, 6 is the first digit and 7 is the second. The first digit covers solids and dust. The second covers water.
A higher second digit is not automatically better for every product. IP67 covers immersion but, oddly, does not by itself guarantee resistance to high pressure jets, which is what a 6 in the second position covers. The ratings describe different tests, not one ladder.
You will have seen the same system on phones. The principle is identical, but what counts as a sensible rating depends entirely on what the product has to survive.
How is it tested?
IP testing is carried out in laboratories using immersion tanks and calibrated spray nozzles, to measure how well a product resists solid particle ingress such as dust or sand, and liquid ingress.
The main method is IEC 60529. You can read more about how it is carried out via this guide to IP ingress protection testing.
Our cables are CE and TUV certified, and carry a 2 year manufacturer's warranty.
Does cable length affect the rating?
No. The IP rating has no connection to cable length. It depends on the sheath material and the sealing at the connectors and any in-line box. A 20m cable and a 5m cable of the same design carry the same rating.
Looking after the rating you paid for
An IP rating describes a cable in good condition. It is not a permanent property, and a few habits protect it:
- Keep the connector caps on when the cable is stored, which is what returns an unmated connector to its rated protection.
- Keep the connector ends off wet ground. Most water problems start with a connector lying in a puddle, not with rain falling on the cable.
- Store the cable in a cable bag rather than loose in the boot, where grit gets into the contacts.
- Do not pull the cable out by the lead. Damage at the point where the cable enters the connector is where the seal fails.
- Check the connectors for grit or corrosion occasionally, and stop using a cable with visible damage to the sheath.
Our guide to keeping your charging cable safe and tidy goes into storage in more detail.
Summary
For a Type 2 charging cable, IP55 sits well above the IP44 that the coupler standards require, and is the right specification for a cable that seals into its sockets while it works. For a 3 pin cable with a control box that lives on the ground, IP67 is the rating that matters.
Treat IP66 as a charge point figure. If you are buying a wall-mounted unit, look for it. If you are buying a cable, look at how the connectors seal, how the cable is built and who stands behind it.
FAQ
Are EV charging cables waterproof?
They are weatherproof rather than waterproof in the everyday sense. A Type 2 connector is sealed against the car and the charge point while charging, and rated to IP44 in that state under the coupler standards. Our Type 2 cables are IP55 and our 3 pin cables are IP67. None of them should be left submerged.
Can I charge in the rain?
Yes. The connectors are designed for it and the connection is sealed once latched. Keep the ends off wet ground and use an outdoor rated socket with a weatherproof cover if you are charging from a 3 pin plug. More in our guide to charging an electric car in the rain.
Is a higher IP rating always better?
Not for its own sake. The rating should match what the product has to survive. A charge point bolted to an outside wall needs more protection than a cable that spends most of its life in a boot, and the two are often quoted together as though they were the same thing.
What cable is used for electric cars?
Type 2 is the standard on effectively every new EV and plug-in hybrid sold in the UK. Type 1 appears on some older models. Type 2 supports single phase and three phase supplies, Type 1 is single phase only.
What are EV charging cables made of?
A cable has conductors, insulation and an outer sheath, with a moulded connector at each end. Conductors are usually copper. The sheath is chosen to stay flexible in cold weather and to resist UV, which is why ours are rated from -30°C to +50°C.
What is CP and PP in EV charging?
Every Type 2 connector has a CP pin, a PP pin and a PE pin. PP stands for Proximity Pilot and handles pre-insertion signalling. CP stands for Control Pilot and handles signalling once connected. PE stands for Protective Earth.
