IoT connectivity for EV charging points: frequently asked questions
If you build, install or operate EV chargers (CPO), these are the most common questions about IoT connectivity, OCPP and multi-carrier.
Why not use the customer's WiFi?+
Because it is rarely reliable, drops when the customer changes router, and your CSMS loses fault control.
How much data does a charger use?+
30-200 MB/month depending on OCPP MeterValues frequency and firmware updates.
Which SIM do I need for OCPP 1.6 / 2.0.1?+
A multi-carrier 4G/LTE-M IoT SIM with private APN and persistent connection to the CSMS.
Is NB-IoT enough for a charger?+
No: OCPP needs bidirectional persistent connection and reasonable latency. Use LTE-M or classic 4G.
Do I need a static IP on the charger?+
Usually not: the charger connects outbound to the CSMS. Static IP only if you manage inbound maintenance yourself.
What about coverage in underground car parks?+
Multi-carrier helps; if there is no signal you need an external antenna or local WiFi gateway.
How do I group chargers by customer or site?+
Labels and sub-accounts in the portal; per-project billing.
Do I comply with electrical regulations?+
Electrical regulations cover wiring; connectivity is covered by your CSMS and our SIM with private APN.
What if the charger loses connection?+
OCPP buffers transactions offline and syncs on reconnect. Our alerts warn the installer.
Do you support soldered MFF2 chip in wallbox?+
Yes, recommended for vibration or vandalism.
And SGP.32 eSIM?+
Yes, ideal for manufacturers who want to swap operator remotely without opening the unit.
How is a charger fleet billed?+
Shared pool or per SIM. For large operators, annual wholesale tariff.
Does it work with any CSMS (Has To Be, Etrel, EVBox, Ampcontrol...)?+
Yes, standard SIMs; just define the private APN to point at your CSMS.
What about roaming for chargers in Portugal?+
EU permanent roaming; the charger connects as in Spain, no regulatory surcharge.
Are there alerts if a charger is down for more than X minutes?+
Yes, per SIM or group rules, with webhook to the CPO's system.
CPO, wallbox manufacturer or installer? We help size SIMs, private APN and SLA.
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