11 Things to Check Before You Buy EV Chargers

Is the charger locked to proprietary software?

This is the first check and the most expensive one to get wrong. You may own the hardware and still not control it, because the software that makes it work belongs to somebody else and can change or stop.

A charger tied to one proprietary platform is a charger that can be made worthless by a decision you are not part of. If that vendor changes terms, is acquired, or discontinues the product, the hardware you paid for can end up dead. Ask specifically whether the unit will operate on a different management platform, and how the fleet is moved there.

• Does it speak standard OCPP to any compliant backend, or only to theirs?
• How does a fleet change management platform, and does it require visiting each unit?
• If the vendor's platform stopped tomorrow, what happens to the chargers?
• Is the configuration exportable, or does it live only in their system?

Is the OCPP connection actually secure?

A great deal of deployed charging talks to its backend with no meaningful security, which means a charger that will accept commands from anything that answers, and a backend that accepts any device claiming an identity.

Ask which security profile the firmware implements rather than accepting a protocol version. Supporting OCPP 2.0.1 does not mean supporting its security profiles, and a unit capable of certificate-based authentication that ships configured without it is configured without it.

Does it support both RFID and OCPP authentication?

These are different mechanisms for different situations and you will want both.

• RFID at the unit, for users who are physically present and for sites where cards are already in use
• Backend authorisation over OCPP, for app, account and remote start
• A local list on the charger, so a basement with no signal still authorises rather than refusing everyone

A charger that supports only one of these constrains how you can operate the site, and that constraint is discovered after installation.

Can it connect an external MID certified meter?

If you are selling energy rather than selling access, the measurement usually has to be legally defensible, and that means a certified meter rather than the charger's internal metering.

The check is whether the charger can read an external certified meter and use those readings as the transaction record. In practice this usually means Modbus integration, and the honest follow-up question is which specific meter models the vendor has actually integrated. Supporting Modbus is not the same as supporting your meter, because every vendor maps their registers differently.

Do they support white labelling, at your volume?

If you intend to sell under your own brand, establish what is actually available and at what quantity. White labelling ranges from a badge on an unchanged product to a genuinely different enclosure and feature set.

• What can be changed: branding, enclosure, display, connector configuration, feature set
• What the minimum quantity is for each level of change
• Whether the software carries your identity as well as the hardware
• Whether the path continues into customisation and technology transfer, or stops at a badge

Is it a standard product or does it have what you need?

Establish whether you are being offered a common standard charger or one that can carry the interfaces and features your deployment actually needs. The two are priced similarly and behave very differently once a requirement arrives that was not in the original specification.

Check the certification

Ask what the unit is certified to, by whom, and for which product. A certificate covering a different variant or an earlier revision is a common and unhelpful answer.

Our own AC chargers are certified to IEC 61851. Certification establishes conformity under defined test conditions. It does not establish that a unit will interoperate with your platform, survive your site, or that the ten thousandth unit is built to the same standard as the one that was tested, which is why the remaining checks on this page exist.

Do they build their own technology or integrate another vendor's?

This is the check that separates a manufacturer from an assembler, and it is not obvious from the outside.

A supplier who bought a third-party control card cannot fix a firmware fault in it, cannot change its behaviour for you, and depends on that card's vendor for its own roadmap. A supplier who developed the control card can do all three. Ask directly: did you design this control card, and do you hold the firmware source?

Either answer can be acceptable. What matters is knowing which one you are buying, because it determines what happens when you need something changed.

What does the warranty actually cover?

Warranties are compared on duration, and duration is the least informative part. The question is scope.

• Is it the control card, or the complete charger including enclosure, cable and connector?
• Are wear items included or excluded, and where is the line drawn?
• Who attends, and who pays when the fault turns out to be the supply or the installation?
• Are firmware fixes covered, and can they be delivered without a site visit?
• What voids it, and does a panel being opened by your own technician count?

What cable is fitted?

Cable is the component most often value engineered and it is a bad place to save money. This is not a general principle. We found it in our own field returns.

Cable quality and the way cable is routed inside the enclosure produce real field failures, and they are failures that pass every end-of-line test and appear months later in somebody else's car park. Ask whether the cable is a branded assembly with a traceable specification or an unnamed one chosen on price, and ask the same about the internal wiring you cannot see.

Will it survive your conditions?

Indian deployments face heat, humidity, salt near the coast and dust almost everywhere. A unit specified for a temperate climate will work and will not last.

• Is the electronics conformally coated? In humid and coastal locations this is the difference between years and months
• What ambient temperature range is it rated for, and does that cover a metal enclosure in direct sun rather than shaded air temperature?
• What is the ingress rating, and does it cover the installed orientation rather than a laboratory position?
• Is there evidence of testing in these conditions, rather than a rating on a datasheet?

Our own units are typically IP65 and adaptable to the deployment. The point of the question is not the number, it is whether the supplier has thought about where the unit is actually going.

And the one question that reveals the most

If you only ask one thing, ask what the field failure rate is and how it is defined.

A supplier who has measured it will answer immediately. One who quotes support call volume is answering a different question, because most calls are the supply, the installation or the vehicle rather than the charger. One who has never measured it will say the number is very low. Ours runs at about 0.5 percent, roughly one unit in two hundred, counting unit failures rather than calls. Ask everyone the same question and compare the answers, including ours.