Network requirements and recommendations for Zaptec products

To function properly, Zaptec chargers need an internet connection to communicate with Zaptec Cloud.
The available communication options vary depending on the charger model you are using: 

• Zaptec Pro: 4G LTE-M, Wi-Fi, PLC (Power Line Communication)
• Zaptec Go: 4G LTE-M, Wi-Fi
• Zaptec Home 4G (Expired): 4G LTE-M (only for ZCH04 <), Wi-Fi
• ZapCharger Pro (Expired): 4G LTE-M (only for ZCS030772 -31071), Wi-Fi

Each charging station uses approx. 5MB for each charge cycle performed. The anticipated data traffic for every Zaptec Pro is around 3 MB daily. 

 

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Network security and communication protocols 

All traffic and communication between the charging stations and the cloud solution are encrypted. All the following network services are required to allow Zaptec Pro to work together with Zaptec Portal. All the ports stated are outgoing ports, and you have to open them in active firewalls. Zaptec Pro links to the necessary services without opening incoming ports, even if they are located behind a NAT.

Protocols  

• 4G LTE-M1 eSIM från Telenor
• WiFi 2.4GHz, IEEE 802.11 b / g / n (fast kanal 1 - 11)
  Minsta signalstyrka på varje laddningsstation: –75 dBm
• Powerline (PLC) – HomePlug Green PHY®, 10 Mbit/s

 

MQTT

TCP port 8883: zapcloud.azure-devices.net

A connection to Azure IoT Hub, which uses MQTT over TLS, acts as a primary communication channel between Zaptec Pro and Zaptec Portal. The condition of the charger is transmitted to Zaptec Portal, and it receives control commands such as start/ stop charging. Communication is encrypted using TLS v1.2, and the server certificate is verified by Zaptec Pro. When it is connected, the server verifies the charger by means of a unique password that is generated during production. More information on Azure IoT Hub can be found here: https://docs.microsoft.com/en-us/azure/iot-hub/about-iot-hub

HTTPS

TCP port 443 (multiple domains)

Zaptec Pro connects to Zaptec Portal by means of HTTPS in order to download firmware updates. This communication is encrypted. Zaptec Pro verifies the server certificate before the update is download, and the firmware update itself is verified cryptographically before being installed.

The following domains are used during firmware updates:

- zapcloud-api.azurewebsites.net

- devices.zaptec.com

- api.zaptec.com

 

Outgoing port

Port	Type port	Domain(s)
123	UDP	no.pool.ntp.org
443	TCP	zapcloud-api.azurewebsites.net devices.zaptec.com api.zaptec.com
8883	TCP	zapcloud.azure-devices.net
53	DNS

 

DHCP

UDP port 68

DHCP is used on the local network to assign an IP address to Zaptec Pro and give the IP address to the DNS server. DHCP server with a sufficient number of IP addresses – one for every device connected. When installing with dynamic IP addresses (DHCP), it is particularly important that the network is dedicated. If the network is shared with others, it is easy to run out of IP addresses, resulting in the chargers risking the connection. If the lease time is too long, it can take time for the chargers to get a new assigned IP address. Since the chargers are individually connected, each charger requires its own IP address, so make sure there is enough in the DHCP.

WPA security: WPA2 for Zaptec Pro

 

DNS

UDP port 53

Zaptec Pro uses DNS look up the IP addresses of the domains used to communicate Zaptec Portal.

If the DHCP server does not specify a DNS server, or if it does not respond promptly, Zaptec Pro uses the DNS server (or DNS servers) specified by the DHCP server, in addition to Google (8.8.8.8) and Cloudflare (1.1.1.1) DNS servers.

 

NTP

UDP-port 123: no.pool.ntp.org

If the Zaptec Pro real-time clock is wrong, the charging station cannot authenticate itself with Zaptec Portal. Zaptec Pro has to be connected to an NTP server to update the internal clock. This communication takes place via UDP port 123.

The NTP server used by Zaptec Pro is no.pool.ntp.org.

The hostname used for NTP is static. It cannot be changed by the user at present.

 

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Troubleshooting

Zaptec devices are designed to automatically reconnect to network i in the event of a failure.

Wireless internet connections can be affected by several external factors.

• Coverage and signal strength
• External influences such as interference
• Local network settings and network equipment

If the charging station has not received a new IP address from the network, the charging station will self-assign an address after several attempts. This happens if the IP address expires and is no longer valid. A restart will force the charging station to try to reconnect.

You should also take a reboot of Wi-Fi extenders, access points, or a repeater.

After reboot, the system will boot in 2-3 minutes.

 

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Recommendations - 4G LTE-M

Coverage

• Ensure your area has 4G LTE-M coverage to work properly. Check coverage maps or use a Zaptec charger with 4G LTE-M activated or a test device.
• Check LTE-M network availability in your area to guarantee reliable connectivity. Use a test device, or a Zaptec charger with 4G activated. Alternatively, check a coverage map provided by the operator.
• General IoT coverage info can be found here: https://www.gsma.com/iot/deployment-map/

Placement

• Avoid placing the charging stations in areas where objects like thick walls or metal can block the signal. Test the coverage in a variety of situations, such as with the garage door open/closed.

Backup

• Always have an alternative communication method, like Wi-Fi or Power Line Communication (PLC), ready in case of LTE-M network issues.

4G LTE-M in the UK

• Zaptec chargers operate exclusively on 4G LTE-M (CAT-M1).
• Support for 4G NB-IoT, which offers better coverage, is being explored.
• 2G/3G networks are not supported.

Currently, 4G LTE-M covers only about half of the UK. Note that having a standard 4G connection doesn’t guarantee LTE-M coverage. For the most reliable setup, we recommend using Wi-Fi or PLC where available.

 

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Recommendations - Wi-Fi

For a reliable connection, follow these recommendations:

• Use 2.4 GHz Wi-Fi (b, g, or n). Ensure your router supports this band.
• Set your Wi-Fi to a static channel (1, 6, or 11) instead of automatic channel selection to avoid interference, especially in areas with multiple access points (APs). 
• Keep the Wi-Fi signal strength at least -75 dBm for stable performance. Tip: Walls, ceilings, and objects like cars can weaken signals. Position your router or access point to maximize coverage.

Signal strength

Signal strength is measured in dBm (decibels per milliwatt) and is a logarithmic scale. This means that if the RSSI is reduced by -3dBm, the signal strength is halved. If it is increased by 3dBm, it doubles. So although the difference between -75dBm and -78dBm may seem small, a signal strength of -78dBm is half of -75dBm. Keep this in mind when placing APs. The minimum signal strength should be -75 dBm for each charger. 

 

Signal strength (dBm)	Performance
-30 dBm	Extremely good
-50 dBm	Excellent
-60 dBm	Very good
-67 dBm	Good (threshold for e.g streaming).
-70 dBm	Weak (limit for surfing, e-mail)
-75 dBm	Weak (the limit value for Zaptec)
-80 dBm	Very weak
-90 dBm	Extremely poor

 

 

Multiple access points (APs)

If you're using multiple access points:

• Use different channels: Ensure each AP is on a unique channel to avoid interference.
• Assign Unique SSID: Give each AP a different network name (SSID) to avoid confusion and ensure the chargers connect to the correct one.
• Power adjustment: When installing access points, make sure to use the correct type. Long-range (LR) is good outdoors,  and short-range (SR) is good indoors. Only set up the power on the APs when needed so they don't interfere with each other. If the AP is close to the chargers, it may be a good idea to lower the power instead.
• Whitelist chargers: Link each charger's MAC address to the nearest AP for a stronger connection. Make sure the APs are on different channels. If there are multiple APs, it is advantageous to "white list" the MAC addresses of the chargers to each AP to prevent chargers from connecting to the same AP or an AP with low signal strength.

Fewer, well-placed APs work better than having too many in poor locations. 

 

Router recommendations

The ISP (Internet Service Provider) is the one that delivers internet via e.g. a switch to your installation. For the best performance, we recommend setting up your own router instead of relying on the ISP's router. This allows you to:

• Control network settings.
• Use an industrial router that is stable and suitable for this type of installation.
• Ensure the ISP is informed about how you intend to set up the network.

 

DHCP

• When installing with dynamic IP addresses (DHCP) make sure the network is dedicated to the chargers to avoid running out of IP addresses.
• Reduce the DHCP lease time so charging stations can get new IP addresses quickly when needed.
• Ensure enough IP addresses are available, as each charging station needs its own address. This is because they are individually connected. 

 

Environmental factors

Wi-Fi signal strength can be affected by:

• Moving parts, such as garage doors or gates.
• Obstructions, like cars, walls, ceilings, and floors.
• Location: Always measure signal strength in the area where the charger will be installed to avoid surprises.

For the best results, consult your network provider to find the optimal location for access points.

 

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Recommendations - PLC

When using PLCs, we recommend using one PLC module per course/cable run.
With long cable runs, we recommend that you install the PLC module close to the charging stations.

Zaptec Pro uses phases L1 and N for PLC communication.

• Use L1 and N as well when installing the PLC module.
• Connection: N + L1 + PE.

On the IT network, note: When you install the PLC module in an IT network, you must only connect to the two phases powering L1 and N at the charging stations (L1 and L3) + PE.
Install it as described in the installation manual.
If the PLC modules are fully encrypted, configure the charging stations as described in the procedure supplied with the PLC module.