Cellular & SIM

The RC500 has a cellular modem with two Nano SIM slots. Configure it under Network - Cellular.

Use the local Cellular page during installation to check live signal, active network mode, session history, and SIM failover state.

SIM cards

• SIM 1 - primary SIM
• SIM 2 - secondary SIM, used for failover when enabled

Caution

Power off the device before inserting or removing SIM cards.

Choose the active SIM, or enable dual-SIM failover, on the Cellular page. Dual-SIM failover is off by default and must be turned on when you want it.

APN

The APN tells the router how to connect a SIM to your carrier’s network. Many SIMs connect automatically. If cellular does not come up, set the APN manually:

Field	Description
APN	The Access Point Name from your carrier
Username	Optional, only if your carrier requires it
Password	Optional, only if your carrier requires it
Auth type	None, PAP, or CHAP, as your carrier specifies
PDP type	IPv4, IPv6, or IPv4v6

The router may ship with a default APN set for one carrier. Set your own carrier’s APN if it does not connect.

Secondary APN policy

Some private carrier plans provide a second APN for a management network, private application, or other restricted service. A supported RC500 can connect that APN on the same modem while keeping its normal cellular connection active.

This is different from dual-SIM failover:

• Dual-SIM failover chooses which SIM supplies the cellular connection.
• Dual APN uses one active SIM and one modem to maintain a primary connection plus one secondary connection.

The secondary policy sends only the listed destination prefixes through the second APN. The router's normal default route stays on the primary connection.

Use the secondary APN only when your carrier or Telisky deployment plan provides all of these details:

• Secondary APN name.
• IPv4, IPv6, or dual-stack service type.
• Optional username, password, and authentication type.
• The destination network prefixes that must use the secondary service.

To configure it locally:

1. Open Network → Cellular.
2. In Secondary APN policy, enter the APN and select the IP family and authentication type supplied by your carrier.
3. Enter each destination as an IPv4 or IPv6 CIDR prefix, such as 10.40.0.0/16 or 2001:db8:40::/48. The prefix family must match the selected IP family.
4. Select Save policy.
5. Select Start dual APN, review the warning, and confirm.
6. Wait for Dual APN active, Primary health: Reachable, and Secondary address: Assigned.

Starting or stopping dual APN briefly re-attaches the primary cellular connection. The router tracks the operation as a job and restores native single-APN mode if the secondary connection or primary recovery check fails. Do not power off the router while the operation is running.

The APN and credentials are write-only: after saving, the page shows that values are stored but does not display them. Leave a write-only field blank to keep its saved value. Use Clear saved credentials before saving if the carrier no longer requires authentication.

To remove the secondary connection, select Stop dual APN and confirm. Wait for Single APN active and verify normal connectivity before leaving the site.

Caution

The secondary APN does not replace or load-balance the router’s normal internet route. Never enter 0.0.0.0/0 or ::/0; default-route prefixes are rejected so ordinary and cloud-management traffic remain on the primary connection.

Signal quality

The Cellular page shows live signal quality. Use this plain reading to judge a location:

Quality	What it usually means
Excellent	Strong signal; best speeds
Good	Reliable for everyday use
Fair	Works, but may slow down under load
Poor	Unreliable; improve placement or antennas

Exact signal values vary by carrier, band, and location, so treat the quality label as the guide rather than any single number. The page also shows detailed metrics (signal strength, band, and network type) that Telisky support may ask about.

Note

Local modem and SIM identifiers may appear on the router for troubleshooting. Before sharing a local Cellular screenshot, redact full IMEI, IMSI, ICCID, phone number, SMS details, and any exact location values unless Telisky Support asks for them through an approved support channel.

SIM failover

When enabled, the router can switch between SIM slots based on connection health and SIM availability, so the site stays online if one SIM loses service. Combine this with WAN failover for the most resilient connection.

Modem restart

If cellular becomes unresponsive, use the modem restart action on the Cellular page and wait for the modem to re-register before changing other settings.

Speed tests and optimization

When cellular is connected, the local Web UI may offer a speed test and guided speed optimization. Use these during setup or troubleshooting, not during customer-critical traffic windows. They can consume mobile data and may briefly reconnect cellular while testing radio profiles.

Modem diagnostics

If Telisky Support needs deeper cellular evidence, use Device services → Modem diagnostics in the local Web UI to capture a redacted support bundle. Send it only through the approved support channel. Do not post raw modem logs, SIM identifiers, or location evidence in public channels.

Modem firmware

The cellular modem has firmware separate from the router. Router firmware and cellular modem firmware are updated separately when those workflows are available. See Firmware Updates.