Aiphone AT-406 Series Box Sets

The AT-406 set ships as a two-station system: one AT-206 master station and one AT-306 sub station. The AT-406B/A version pairs an AT-206B master with an AT-306B sub. You can expand it with up to two more sub stations (AT-306 or AT-306B), for a maximum of one master and three subs.

Sub stations call the master station only. The master can call every connected sub station, but there is no station-to-station path between subs. If you need any room to ring any other room, this is the wrong architecture for the job.

Two-conductor with overall shield, and Aiphone specifies its own #822202 cable for the run. It is a handset system with full-duplex communication, so the shielded pair is doing both directions of audio on that one cable.

On a two-station set the master-to-sub run is 2,300 feet with 22 AWG or 5,250 feet with 18 AWG. Once you add the third sub station the allowance drops to 1,350 feet at 22 AWG and 3,100 feet at 18 AWG. For long runs in a warehouse or across a campus building, step up to 18 AWG rather than pulling 22.

No. The AT-406 is a handset master-and-sub office intercom, not a door answering set, and nothing in it is a door station. For a door application look at the Aiphone C-123L/A ChimeCom set or the CCS-1A ChimeCom 2 set, each of which pairs one door station with one master station. If you need door release with keypad entry, the Aiphone LEM-1DLS Access Sentry set covers that.

They solve different problems. The AT-406 set pairs one AT-206 master station with one AT-306 sub station for handset, full-duplex communication between interior stations, where the master calls all connected sub stations and each sub station calls the master only. The Aiphone C-123L/A is a ChimeCom set configured as 1 door station and 1 master, so it is built for answering someone at an entrance rather than talking room to room. Choose the AT-406 for staff-to-staff intercom between rooms and the C-123L/A when the second station needs to sit at a door.

Look at the Aiphone LEM-1DLS Access Sentry set, which comes as an LE-D door station, an LEM-1DL master station, and a PT-1210N power supply, so it arrives with its own transformer for a powered installation. The AT-406 set is an interior master-and-sub arrangement running on 6V DC or four AA batteries, with up to two additional AT-306 or AT-306B sub stations added to the master. Use the AT-406 for room-to-room handset communication and the LEM-1DLS where the entry station is part of the scope.

The AT-406 set runs on 6V DC or four AA batteries, so a battery install is an option where no transformer location is convenient. The Aiphone LEM-1DLS Access Sentry set is supplied with a PT-1210N power supply as part of the set. That is the practical difference on a retrofit: the AT-406 can go in without pulling a dedicated power circuit, while the LEM-1DLS arrives expecting its transformer to be mounted and connected.

The AT-406 set is the expandable one in this group: up to two additional sub stations, AT-306 or AT-306B, can be added to the master station, with master-to-third-sub-station wiring runs of 1,350 feet at 22AWG or 3,100 feet at 18AWG using 2-conductor overall shielded cable such as Aiphone #822202. The Aiphone C-123L/A and the Aiphone CCS-1A are each supplied as one-door, one-master sets. If the plan calls for three interior talk points off a single master, specify the AT-406 series.

Two colors: white and charcoal gray. If you are adding to an existing AT-206/AT-306 install, order the color that matches the stations already on the wall, since the added subs are AT-306 or AT-306B units in their own right.

It is classified as commercial door hardware equipment in the electronic access control family, and the handset full-duplex format with runs up to 5,250 feet on 18 AWG suits offices, shops, and back-of-house use rather than a home doorbell role.