Intercom handset equivalence table: which Tegui model replaces yours

Do you need to replace an automatic door entry intercom handset and do not know which model is compatible with your installation? In this intercom handset equivalence table, we help you identify which Tegui terminal can replace your old intercom handset and what you should check before disconnecting a single wire.

It is one of the queries we receive most frequently: we have an old intercom handset from Tegui, Fermax, Golmar, Auta, BTicino, or another brand; it stops working, and we want to replace only the unit inside the home without replacing the entire installation.

In many cases, it is possible, but there is one fundamental condition: the new intercom handset must be compatible with the technology of the existing installation. It is not enough for it to have the same number of wires, look physically similar to the old one, or be from the same brand.

In this guide, we explain how to distinguish the main systems, how to use the equivalence table, and which Tegui models to consider for conventional 4+N installations and 2-wire systems.

Which automatic door entry system do you have: 4+N, Teguibus, or 2-wire?

Before looking for an equivalent, we must identify the system. This step is much more important than choosing the design of the new intercom handset.

Two apparently similar terminals may use completely different technologies and therefore not be interchangeable.

Important: counting the wires can help us get our bearings, but we must not use only the color or number of conductors as definitive proof. Older installations may have unused wires, reused wiring, or different technologies that look very similar externally.

Whenever possible, we recommend checking:

• The exact reference of the intercom handset we are going to replace.
• The reference of the outdoor panel or audio module.
• The numbers or letters of the terminals where the wires are connected.
• Whether the terminal includes configurators, jumpers, or programming elements.
• What technology the rest of the building uses.

Before disassembling the intercom handset: take a photograph

This simple step prevents many problems. Before removing any conductor, we recommend taking a clear photograph showing the wires and the numbering of all terminals.

We can then label each conductor with a small tag. Wire color does not universally determine its function: a blue wire may have one function in one home and a completely different one in another installation.

We must never establish an equivalence based solely on colors.

Equivalence table for the Tegui T-71U 374240 intercom handset in 4+N systems

The Tegui T-71U Ref. 374240 is one of the main solutions for replacing intercom handsets belonging to compatible conventional 4+N installations.

Its purpose is precisely to adapt the connections of numerous old intercom handsets from manufacturers such as Tegui, Fermax, Golmar, Auta, Urmet, Bitron, Aiphone, Terraneo, and other brands included in its equivalence documentation.

What does each terminal on the Tegui T-71U mean?

To carry out the replacement correctly, we must first understand the function of each connection on the new intercom handset.

How to use an equivalence table correctly

We must not copy the wires based on their colors. What we need to transfer from one intercom handset to another is the function of each terminal.

1. Identify the brand and model of the old intercom handset. Look for a reference on the casing, base, circuit board, or inner label.
2. Take a photograph before disconnecting. The wires and terminals must be clearly visible.
3. Locate the old model in the equivalence table.
4. Note the correspondence between terminals. The table will indicate which old connection corresponds to 1E/1Z, 2, 3, 4, and 5 on the T-71U.
5. Disconnect the wires one by one and label them.
6. Connect each function to the corresponding terminal on the T-71U.
7. Check calling, two-way audio, and the door release.

✅ Check the price and availability of the Tegui T-71U Ref. 374240 →

Is the Tegui T-71U suitable for any old handset?

No. The fact that the T-71U is a universal handset does not mean it can be installed in any door entry system.

This is probably the most important confusion we need to avoid.

The T-71U is intended for compatible 4+N conventional systems. We should not install it directly to replace a handset belonging to another type of technology simply because both devices are Tegui.

For example, a Tegui T-72 digital and a Tegui T-71U may belong to the same brand and look familiar, but they work with different systems. Therefore, we should not transfer the two wires from one to the other expecting it to work.

Real example: I have five wires, but I do not know which system the building uses

This situation often occurs after a renovation. The old handset has disappeared, and we only find several wires coming out of the wall.

In this case, we do not recommend buying a T-71U solely because we see five wires.

We must ask which system the building currently uses, locate the reference of another installed handset, or identify the outdoor panel and its components.

If it is confirmed to be a compatible 4+N conventional installation, the T-71U may be a solution. If the building uses a BUS system, we must look for the handset corresponding to that technology.

Handsets for 2-wire Tegui and BTicino systems

Current Tegui and BTicino installations widely use 2-WIRE technology. This is a different architecture from the traditional 4+N conventional system.

In an installation of this type, communication, ringing, and other functions travel through the BUS. For this reason, we cannot use a conventional 1E, 1Z, 2, 3, 4, and 5 table as if we were working with an analog handset.

Tegui T-75 Series 7 Ref. 374290

If the installation belongs to the Tegui 2-wire system compatible with this handset, one option to consider is the Tegui T-75 Series 7 Ref. 374290.

Attention: We should not install the T-75 as a replacement for a conventional 4+N door phone solely because only a few wires reach the old device. We must first confirm the technology.

✅ View Tegui T-75 Series 7 Ref. 374290 →

Tegui Series 8 door phone Ref. 374794

Another option for certain 2-wire installations is the Tegui Series 8 door phone Ref. 374794.

Again, before replacing equipment, we must verify the existing model, the system, and its configuration.

✅ View Tegui Series 8 door phone Ref. 374794 →

Common mistakes when replacing a door phone

A significant proportion of the faults that appear after replacing a door phone do not originate in the new device, but rather in incorrect identification of the system or wiring.

1. Copying the connections according to the wire color

There is no universal color code that can be applied to all automatic door entry system installations.

The correct reference points are the terminals and their functions, not the colors originally chosen by the installer.

2. Assuming that two Tegui devices are necessarily compatible

Tegui has marketed different generations and technologies. A conventional door phone, a Teguibus terminal, and a modern 2-wire device should not be considered equivalent simply because they are made by the same manufacturer.

3. Buying first and checking the installation afterward

It is preferable to spend a few minutes identifying the reference and photographing the wiring before placing the order.

In addition to saving time, we will avoid unnecessary dismantling and reduce the risk of choosing an incompatible product.

4. Removing all the wires at once

If we do not have installation documentation, removing all the wires without photographing or labeling them can make replacement much more difficult.

We recommend identifying and marking each connection before dismantling the old device.

5. Mistaking a fault for an incompatibility

After installing the door phone, the door opener may work but not the audio, we may be able to hear but not be heard, or everything may work except the call.

That does not automatically mean that the door phone is defective. There may be an equivalence error, an incorrect selection between electronic call and buzzer, or it may simply be a terminal that is incompatible with the system.

Practical example of replacing an old handset

Suppose we arrive at a home and find an old handset with five connected wires.

The professional procedure would be as follows:

1. We photograph the complete unit and its connection terminal block.
2. We note the brand and reference.
3. We check which technology the installation uses.
4. We look for the model in the equivalence table.
5. We identify the functions: call, common, door release, microphone, and speaker.
6. We mark the wires before disconnecting them.
7. We map the connections to the terminals of the new handset.
8. We test the call from the entrance panel.
9. We check communication in both directions.
10. Finally, we verify the door release.

If we discover during the process that the old equipment belongs to a digital or BUS system, we stop the replacement and look for a terminal compatible with that technology instead of trying to adapt the T-71U.

Cannot find your handset in the equivalence table?

Some installations have been operating for decades, and we still encounter handsets from manufacturers and with reference numbers that no longer appear in current catalogues.

If you cannot identify the model, the most useful approach is to gather this information:

• Front-facing photo of the handset.
• Photo of the inside.
• Clear photo of the connection terminal block.
• Numbers and letters shown next to each terminal.
• Product reference, if it is still legible.
• Number of wires actually connected.
• Photo of the entrance panel, if possible.

With this information, it is much easier to determine which technology the installation uses and whether a compatible replacement is available.

You can also view our selection of available Tegui and BTicino handsets.

To view the rest of our professional solutions, spare parts, monitors, kits, and components, visit Tegui-Distel.

Frequently asked questions about handset equivalents

Can I replace a 5-wire handset with a 2-wire Tegui handset?

Not directly. A conventional 4+N system and a 2-wire BUS system use different technologies. Switching from one technology to the other may require work on other installation components, not just replacing the handset in the home.

Is the Tegui T-71U compatible with 2-wire systems?

We must not use the T-71U as a replacement for a 2-wire BUS terminal. The T-71U Ref. 374240 is intended for compatible conventional 4+N systems.

Can I replace a Tegui T-72 with a T-71U?

They are not direct replacements. The T-72 belongs to a different digital technology from the conventional system used by the T-71U. We must look for equipment compatible with the installed system.

How do I know where to connect each color on a Tegui T-71U?

We must not use color to determine the connection. Colors are not standardized across all installations. We need to identify the function performed by each conductor in the previous intercom and transfer it to the equivalent terminal on the T-71U.

My old intercom has no brand or reference. What should I do?

Photograph the terminal strip and note the numbers or letters on the terminals. It is also useful to identify the external panel and ask which system the building uses. With this information, we can look for the equivalent much more safely.

What is the difference between 1E and 1Z on the Tegui T-71U?

These are two different types of call input. 1E corresponds to an electronic call, and 1Z to a buzzer call. We must use the one corresponding to the system being replaced.

Can I install an audio intercom where there used to be a video monitor?

It depends on the installation technology. There are older systems for which audio-only alternatives may exist, but we cannot generalize. We must first identify the monitor reference and the system it belongs to.

Summary: how to choose the right equivalent intercom

To safely replace an old intercom, we must follow a simple rule: first identify the technology, then look for the equivalent.

In compatible conventional 4+N systems, the Tegui T-71U Ref. 374240 is one of the most important solutions for replacing numerous old intercoms. In 2-wire Tegui or BTicino installations, we must use terminals specifically designed for this technology, such as compatible Series 7 or Series 8 models.

The equivalence table allows us to correctly transfer the functions of the old device to the new one, but it does not make two different technologies compatible.

Before buying: identify the reference, photograph the wiring, and check the system. It takes three minutes and can help prevent an incorrect replacement.

🛒 View all Tegui and BTicino intercoms →

✅ Buy Tegui T-71U Ref. 374240 →