Videx 3000 Series — Fault Finding & Replacement Guide

Written after a real job (Kenilworth Court, Generations Property Management) that took far longer than necessary because a replacement part was fitted before the system's full specification was confirmed. Read this before touching any Videx 3000 series system.

System Overview

The Golden Rule — Establish System Spec Before Ordering Anything

Before ordering or fitting any replacement part on a Videx door entry system, confirm all of:

1. Power supply type — is the panel module running on AC, DC, or both? Check the PSU label (e.g. Art.520M outputs +12Vdc, +8Vdc, and 13Vac — but not every module uses all three outputs).
2. Panel module model — remove the front cover and check the label on the back of the unit. Note the full Art. number.
3. Housing type — 3000 series surface housing, 4000 series, or 8000 series? Modules are not interchangeable between housing ranges without a full housing swap.
4. Handset model — check the label on the back of the handset in one of the flats. Note the full Art. number (e.g. 3101, 3102, 3112).
5. Wiring type — count the cores: 3+N (3-wire bus plus 1 per button) or 4+N (4-wire bus plus 1 per button)?
6. Check the Videx compatibility chart — videx.co.uk/compatibility-chart.html — before ordering any replacement module or handset. Don't rely on a supplier's "replaces X" marketing copy.

Power Supply — Art.520M Output Summary

Critical: just because a PSU provides AC does not mean the panel module uses it. Always check the module spec, not just the PSU label.

Module Compatibility — Key Differences

The 8836M-1 and 4837-1 are not physically interchangeable with 3000 series housing. If replacing an old 3000 series module, you need either the correct 3000 series replacement or a full housing/button set change.

Handset Compatibility

Videx 3101 / 3102 / 3111 / 3112 Terminal Layout

Key differences between models

• 3101 — AC buzzer + electronic call tone, door open + service button
• 3102 — as 3101, plus privacy switch (for AC buzzer only)
• 3111 — electronic call tone only (no AC buzzer), terminal 6 unused
• 3112 — as 3111, plus privacy switch

Similar-looking model numbers differ in AC buzzer support and privacy switch — always confirm the exact Art. number off the handset label rather than assuming from a photo or a previous visit's notes.

Compatibility with the 4837-1 panel

The 4837-1 panel (4+N wiring, DC powered) is confirmed compatible with: 3021, 3101, 3102, 4842–4845, 380N, 502, 512R. Source: Videx compatibility chart.

Wiring — 4+N System Terminal Mapping

Wire colours below are as found on one real site (Kenilworth Court) — colours are not a universal Videx standard, always trace or test rather than assuming a colour scheme carries between installations.

At the panel (Art.4837-1 or Art.837-1)

At each handset (3101/3102/3112)

Buzzer Call — Critical Capacitor Requirement

Symptom: when AC is fed to the call button common to drive the apartment buzzers, a loud screaming/feedback noise is heard through the door speaker.

Cause: the AC buzzer signal back-feeds into the speech circuit via the common wiring.

Fix: Videx mandates a 0.1µF (100nF) capacitor fitted between terminals 6 and 3 at each handset when using any handset with AC buzzer call (3101, 3102, 3001, 3021, SMART1/2, 924/926).

Source (Videx official): 800N_A4.pdf

Capacitor to order: EVOX RIFA Class X2, 0.1µF, 250VAC — CPC Farnell part CA06050

One capacitor required per handset. For a 6-flat block, order at least 8 (2 spares).

Fault Finding — Step by Step

No audio at door panel (speech fault)

1. Check terminal 3 (speech ground) is properly connected at the panel and returns to the system negative.
2. Check terminal 1 (speech in) and terminal 2 (speech out) are continuous between panel and handset.
3. Test microphone resistance — a healthy electret mic reads approximately 1kΩ. Open circuit or dead short = faulty mic.
4. If mic tests good and wiring is intact, suspect internal panel module fault.

No door release

1. Confirm the orange (lock) wire is on terminal 5 at the handset, and routes to the panel's S terminal (relay contact).
2. Check the lock's negative return is on the panel's S1 or relay common — not wired direct to the negative rail.
3. Confirm DC power is reaching the panel module.

No call / buzzer not ringing in flat

1. Confirm the white switch wire for that flat runs from the call button P terminal at the panel to terminal 6 at the handset.
2. Check AC is present on the call button common — if not, the buzzer won't ring.
3. If AC on common causes screeching, fit the 0.1µF capacitor between terminals 6 and 3 at the handset (see above).
4. If the buzzer still doesn't ring after the capacitor is fitted, try terminal 4 (electronic call tone) as an alternative — wire C1 from panel to terminal 4 at the handset.

Module replaced but system won't work

1. First question: what power does the new module require? AC or DC?
2. Second question: what power does the existing cable deliver to the panel? Measure it.
3. If mismatch — you cannot make it work without rewiring. Do not waste time fault finding further.
4. Check housing compatibility — 3000/4000/8000 series housings are different.

Common Issues

Lesson Learned — Kenilworth Court Case Study

Job: Replace faulty panel module at a 6-flat Videx door entry system (Generations Property Management, Kenilworth Court Block 7–12).

What went wrong:

• Supplier recommended Art.8836M-1 as a replacement without knowing the system spec.
• 8836M-1 requires 12V AC. The existing wiring delivered only DC to the panel.
• Module was fitted before power type was confirmed. Hours of fault finding followed.
• A 4837-1 (DC powered) was then tested and worked immediately — but doesn't physically fit the 3000 series housing.
• Eventually confirmed: the old module was internally faulty (mic tested good, DC fuse was a separate issue). System retained with existing DC wiring, 8836M-1 abandoned.
• Buzzer call required an AC feed to the button common plus 0.1µF capacitors at each handset — a return visit was required for all 6 flats.

Total time lost vs what it should have been:

• Actual: over a full day across multiple visits.
• Should have been: 2–3 hours if the system had been fully specced first and the correct DC-compatible module ordered from the outset.

What to do on any future similar job:

1. Before touching anything — photograph the panel module label, PSU label, and one handset label.
2. Check the Videx compatibility chart.
3. Confirm AC vs DC supply with a multimeter.
4. Order the correct module for the existing power supply and housing.
5. If the system is old and obsolete, price up a full replacement kit (module + housing + buttons) rather than just the module — a full swap is often faster and cleaner than trying to retrofit into an old housing.

Useful Links

• Videx compatibility chart
• Videx 3102 quick guide
• Videx 3101 quick guide
• Videx 3000 series full technical manual
• Videx buzzer capacitor requirement
• CPC Farnell 0.1µF X2 capacitor

Related Documents

• Getting Started — Door Entry & Access Control
• Videx 4G GSM — Art. 4812 & 4812R
• Fermax City Classic — One-Way Audio Fault