In a multi-building apartment community, the unit outdoor station is the device at each building entrance—the station that residents and visitors actually approach. It has to know which building it belongs to, which apartments it serves, and how to route a call to the correct indoor monitor. That knowledge comes from one configuration step: address coding.

Address coding is not glamorous. It does not appear in product marketing, and it is rarely discussed in sales conversations. But it is the step that determines whether a visitor pressing a call button reaches the right apartment, whether the room list at each entrance shows only the units that belong there, and whether the property manager can manage access building by building rather than untangling a system-wide mess.

For integrators commissioning a multi-building project, and for distributors supporting installers in the field, understanding unit outdoor station address coding is essential. FARHD, a Chinese manufacturer founded in 1998 with 28 years of experience in video door phones and intercom systems, designs its IP apartment systems with configurable addressing so that each unit station can be correctly identified within the community—and produces core components in-house, allowing the addressing logic, display, and call routing to be designed as one coordinated system.

What “Unit Outdoor Station” Means in a Multi-Building Community

The terminology matters, because it determines what the address is actually identifying.

In a residential community, the hierarchy typically runs:

Community → Building → Unit (staircase/entrance) → Floor → Apartment

In this context, a “unit outdoor station” is the station mounted at the entrance of a specific building unit—the entrance that serves a particular staircase or block of apartments. A community with 12 buildings and 2 units per building has 24 unit outdoor stations, each serving a defined set of apartments.

Each unit outdoor station must be addressable within the system, so that:

• Calls route correctly. A visitor at Building 3, Unit 2 calls an apartment in that unit, and the call reaches the right monitor—not an apartment in a different building.
• The room list is scoped correctly. Each entrance station should display the apartments that belong to that unit, not the entire community’s directory.
• Management is organized. Card permissions, directory updates, and access records can be managed per building or unit rather than as one undifferentiated list.
• Troubleshooting is possible. When a call fails, the address tells the technician where to look.

Without address coding, the system is a flat collection of devices with no reliable relationship between physical location and digital identity.

The Addressing Hierarchy: What Each Address Component Does

Most IP apartment systems use a structured address that reflects the physical hierarchy. The exact format varies by manufacturer and firmware version, but the components are typically:

Building number. Identifies which building the station serves. In a community with multiple buildings, this is the first level of differentiation.

Unit number. Identifies which entrance/staircase within the building. A building with two staircases has two unit outdoor stations, each with its own address.

Device or station number. Some systems use an additional identifier for the specific device, particularly when a unit has more than one outdoor station (for example, a main entrance and a secondary entrance).

The full address is often expressed as a combination—for example, Building 03, Unit 02—and this combination must be unique within the community.

Room numbers are a separate but related configuration. The apartment room numbers (1-digit or 2-digit, as discussed in FARHD’s room number settings) are configured within the scope of the unit station. The address identifies the station; the room numbers identify the apartments it serves. Both must be consistent for calls to route correctly.

Why Address Coding Is Easy to Get Wrong

Address coding looks simple—assign a number, save the setting. In practice, several factors make it error-prone, especially in large projects.

Buildings are completed in phases. A community may be handed over building by building. If addresses are assigned as each building is commissioned, without a master plan, the numbering can become inconsistent—Building 5 might be addressed as “05″ in phase one and “5″ in phase three.

Physical numbering and system numbering diverge. The developer’s building numbering (often displayed on the façade) may not match the electrical plan’s numbering or the property management’s internal numbering. If the system address follows one scheme and the room list follows another, visitors and residents will be confused.

Units are added or reconfigured. A building originally designed with one entrance may later add a second. The new station needs an address that fits the existing scheme, which requires the original scheme to be documented.

Multiple vendors are involved. In large projects, the intercom system may be installed by one contractor, the network by another, and the property management software by a third. If the addressing scheme is not shared and documented, integration becomes guesswork.

Testing is incomplete. Commissioning often tests a sample of apartments rather than the full directory. An address error in a unit that was not tested may not surface until a resident complains—after handover.

The cost of these errors is not the configuration time. It is the service visits, resident complaints, and reconfiguration work that follow.

Setting Address Codes on the Unit Outdoor Station

The exact procedure varies by model and firmware, but the general workflow is consistent across FARHD IP apartment systems.

Before You Begin: Establish the Scheme

Do not start entering addresses until the community’s numbering scheme is defined and documented.

1. Confirm the physical hierarchy. How many buildings, how many units per building, and how are they numbered on the façade and in the developer’s documentation?
2. Decide the address format. Will the building number be 1 or 2 digits? Will the unit number be 1 or 2 digits? Is a separator used? The format should match the project’s scale and the management software’s expectations.
3. Confirm the room number scheme for each unit. Which apartments belong to which unit station, and what are their room numbers? This determines the directory that each station will display.
4. Document the scheme before configuration. A simple table—building, unit, station address, room range—prevents most errors. It also becomes the handover document.

The Configuration Workflow

The general sequence for setting the address on a unit outdoor station:

1. Access the station’s configuration menu. This may be done directly on the station’s touch screen, through a configuration tool, or through the management center, depending on the system architecture. For an 8″ touch screen station, the settings menu is typically accessible on-device.
2. Locate the address or device settings. The menu label may be “Address Settings,” “Device Address,” “Unit Number,” or similar, depending on the firmware version.
3. Enter the building and unit numbers according to the documented scheme. Confirm the input before saving—mis-entered digits are the most common source of routing errors.
4. Save and confirm the setting. The station should acknowledge the change. Some systems require a restart for the address to take effect.
5. Configure or verify the room list scope. Confirm that the station’s directory is scoped to the apartments that belong to this unit. If the room list is generated from the management center, confirm that the station’s address matches the directory it is assigned.
6. Test call routing from the station to a sample of apartments in that unit—including the first, last, and a middle unit—to confirm that calls reach the correct monitors.
7. Test that calls do not route to apartments outside the unit. This is the check that catches address scoping errors: a station should not be able to call apartments in a different building or unit.

Where the Address Is Set: On-Device vs. Management Center

There are two common models, and the choice affects the workflow:

On-device configuration. The address is entered directly on the outdoor station’s interface. This is convenient for commissioning, because the technician is already at the station. It is also the model most prone to inconsistency, because each station is configured individually and there is no central validation.

Management center configuration. The address is assigned from the management software, and the station receives it over the network. This supports consistency—the system can detect duplicate addresses and enforce the scheme—but requires the station to be network-connected and registered before addressing.

In practice, many projects use a hybrid: initial addressing on-device during installation, followed by verification and any corrections through the management center. The important discipline is the same in both models: document the scheme, configure against it, and verify the result.

Address Coding in Multi-Building Communities

In communities with multiple buildings, the building number becomes the primary differentiator, and the unit number differentiates entrances within a building.

A few practical points for this scenario:

Use consistent digit lengths across buildings. If Building 1 is addressed as “01,” Building 10 should be “10″—not “010″ or “1.” Inconsistent digit lengths complicate directory generation and can cause sorting errors in the room list.

Reserve capacity for future phases. If the community will eventually have 20 buildings, plan a 2-digit building number from the start, even if only 8 exist today. Changing the format mid-project is far more disruptive than planning for it.

Confirm the relationship between address and room number. In some schemes, the room number incorporates the building or unit (for example, Building 3, Unit 2, Apartment 501 might be coded as 3-2-501 or 32-501). In others, room numbers are scoped within the unit station, and the address provides the building/unit context. The two approaches work, but they must be chosen deliberately and applied consistently.

Verify cross-building isolation. Test that a call from Building 3′s station cannot reach an apartment in Building 4. This is the definitive check that address coding is working as intended.

Common Address Coding Mistakes and How to Avoid Them

Verification: The Step That Catches Everything

Address coding is only as reliable as the verification that follows it. A practical commissioning sequence for each unit outdoor station:

1. Confirm the address displayed or stored matches the documented scheme.
2. Test calls to the first apartment in the unit’s scope.
3. Test calls to the last apartment in the unit’s scope.
4. Test calls to a middle apartment to confirm routing across the directory.
5. Test that a call cannot reach an apartment outside the unit’s scope—the cross-scope isolation check.
6. Verify the room list displays the correct apartments and ordering.
7. Record the test result in the commissioning documentation, including which units were tested and which were not.

For large communities, testing every apartment is impractical, but the first/last/middle plus isolation checks catch the vast majority of address errors. A documented test record also protects the integrator if a dispute arises later about whether the system was commissioned correctly.

Documentation: The Handover Artifact That Saves Future Work

The addressing scheme should be documented at handover, not left in the commissioning technician’s memory. The handover file should include:

• The address format and digit lengths used
• A table of buildings, units, station addresses, and room ranges
• The room list structure for each station
• The verification record from commissioning
• The procedure for adding a new station or unit in the future

This documentation is what makes the system maintainable across staff changes—and property management staff changes are frequent. Without it, a new building added in a later phase requires reverse-engineering the original scheme from the installed devices.

Where FARHD’s Manufacturing Model Helps

FARHD’s in-house production of TFT LCD screens, driver boards, and camera modules supports address coding in practical ways. Because the display, interface, and firmware are developed together, the address configuration menu and the room list display can be designed to work coherently—so the address a technician enters is visibly reflected in what the station displays and calls. Interface layouts can be verified on the actual hardware, so menus do not truncate or misrepresent address fields. And customization for OEM and ODM projects can extend to addressing formats and directory structures for specific markets.

FARHD products hold international certifications including CE, FCC, RoHS, IP65 water resistance, and EMC. Founded in 1998 with 28 years of industry experience and supported by 28 direct sales branches across China, FARHD has completed over 10,000 large-scale building video intercom projects, including ultra-large communities with 1,000, 3,000, and even over 5,000 households. At that scale, address coding is not a minor configuration detail—it is the foundation of a system that either works smoothly for thousands of residents or generates complaints daily. That experience informs how FARHD approaches addressing schemes, documentation, and commissioning support for apartment projects.

FARHD also provides a hassle-free after-sales service system: upon product delivery, a dedicated technical support group is established to assist with programming, device installation, and wiring connections throughout the process—including guidance on address coding and directory configuration during commissioning.

Set the Address Right, and Everything Else Follows

Unit outdoor station address coding is the configuration step that connects physical location to digital identity. Get it right, and calls route correctly, directories are scoped properly, and management is organized by building and unit. Get it wrong, and the errors surface at the door—in front of residents and visitors, at the moment when the system is supposed to be working.

The discipline is straightforward: define the scheme before you configure, use the physical building numbering as the reference, keep digit lengths consistent, verify with first/last/middle and isolation tests, and document the result. In a multi-building community, that discipline is what turns a collection of outdoor stations into a working system.

Whether you are commissioning an apartment development, upgrading an existing building’s entrance, or building a private-label product line with OEM/ODM support, FARHD can support your project from core components to global delivery.

We look forward to building a strong partnership with you and jointly shaping the future of smart living.

Email: info@farhd.com
Website: www.farhd.com
WhatsApp: +86 188 2370 9809 / +86 199 2545 1918