CELLPRIM4GE SIM installation guide

Which SIM does the BFT CELLPRIM4GE take?

A nano SIM (4FF), voice-capable, active before install. The CELLPRIM4GE is BFT's 4G-era cellular intercom — the one to fit as the 2G Cellula and CellCom+ stock ages out — and the SIM shrinks a size with the generation change: nano, not the old standard card.

Which network?

Any UK network with 4G at the gate. Being 4G, it's indifferent to the 2G/3G switch-offs — the question is purely signal at the panel. A multi-network SIM settles it: strongest carrier at the gate, automatically, for the life of the install.

Spend cap on pay-monthly SIMs.

Fitting the SIM

For the installing engineer, power down:

1. Open the unit; fit the nano SIM in the holder on the controller board.
2. Antenna connected before power, mounted for height and clear air.
3. Different networks need different APN settings on this generation — have your SIM provider's APN ready.

First power-up

Let it register, set the APN if required, program per the dealer manual (app or SMS depending on version), and test the full chain: button, call, keypress, relay.

If it won't connect

• Registers but features fail: APN values.
• No registration: SIM active, PIN off, 4G present — phone test at the gate.
• Weak audio or drops: antenna position before SIM swaps.

FAQ

Upgrading from a Cellula — what changes? SIM size (standard to nano), network (2G to 4G), and APN configuration. Relay wiring carries over.

Will it outlast the switch-offs? Yes — that's its purpose.

Voice or data? Voice-capable for the calling intercom functions.