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How to fit a door handle alarm so the first night stays quiet

Updated: October 2026

You have locked the front door, and a small siren is on the hall table. How to fit a door handle alarm keeps that first night quiet: switch the unit off, hang it so it cannot swing, arm it, then test in daylight. The two Defender models on the [window handle with alarm comparison](/hub/door-and-window-security/window-handle-with-alarm) use different controls, so follow the sheet in the box. The Products Compared editorial team used the listings and Defender's August 2025 PDFs, checked on 15 October 2026. A purchase through our links can earn a commission at no extra cost to you.

You have locked the front door, and a small siren is on the hall table. How to fit a door handle alarm keeps that first night quiet: switch the unit off, hang it so it cannot swing, arm it, then test in daylight.

Our top picks

Defender Defender Ultra Slim

Best overall

Defender Defender Ultra Slim
7.2/10about £9.95
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Defender Defender door handle alarm

Rank 2

Defender Defender door handle alarm
8.8/10about £9.95
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HERCHR HERCHR handle alarm

Alternative

HERCHR HERCHR handle alarm
4.0/10about £10.99
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On this page
  1. 1.Hang it before you arm it
  2. 2.The EL00002 on a metal handle
  3. 3.Cord or pad on the EL00237
  4. 4.Test in daylight

Hang it before you arm it

Hang the unit so it cannot swing, and leave it switched off until the hang is finished. The EL00002 uses a dial. The Ultra Slim sheet says to keep that model off while you fit it. Neither sheet documents a remote. A hook or a cord is the whole fit, with no drill and no wire back to a panel. Take keys and chains off the lever for the first hang. Hotel packing is on the hotel door handle alarm page.

The EL00002 on a metal handle

Defender's August 2025 EL00002 sheet says to hang it on a metal handle, pull the battery tab, and start on the lowest sensitivity dot. Turn the dial up from 0 to switch on, and back to 0 to switch off. Three dots is the highest mark. If the siren sounds before you touch the handle, stay on the lower dot. That PDF gives a 6-second exit delay, which the amazon.co.uk bullets leave out. Step an arm's length away and use those 6 seconds to clear the handle. A plastic window handle sits outside that sheet.
Defender Defender Ultra Slim

Testsieger

Defender Defender Ultra Slim
7.2/10about £9.95
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Cord or pad on the EL00237

Tighten the Ultra Slim cord so the body cannot fall, with the unit still switched off. Defender's August 2025 sheet then gives a 7-second delay, one beep, and a siren of 30 seconds. After that siren stops, another 7 seconds pass and it can sound again. Keep the 6-second delay on the EL00002. A swing means the cord is still slack. Skip the pad when the handle itself should trip the siren. The sheet says the pad can mark the surface and weaken handle detection. One buyer stuck a unit to glass, heard nothing, and then tied it to the window handle.

Test in daylight

Test in daylight with spare keys off the handle. On the EL00002, choose the lowest dot, stand an arm's length away, wait the 6 seconds, move the handle, then return the dial to 0. If it sounds before you touch the handle, leave the dial lower. Wind, rain or the closing swing can do that. On the Ultra Slim, a draught that shifts the body means the cord is still too long. Stop if the window must lock, or if a new hole might void the window firm's guarantee. Matching a hanger is the job of the best window handle alarm page. The window handle alarm buying guide sets the trade-offs before you buy.

Common questions

Which way does the EL00002 dial turn?
Turn the EL00002 dial up from 0 to switch on, and back to 0 to switch off, as Defender's instructions describe. The dots are sensitivity, so start on the lowest. Three dots is the maximum, and buyers find that top mark trips while the unit is still being placed. If the siren sounds before you touch the handle, stay lower. The Ultra Slim has its own switch, so those dots belong to the EL00002.
How long is the exit delay on each Defender?
The EL00002 sheet gives 6 seconds to step away after you arm it. The EL00237 sheet gives 7 seconds, one beep, a 30-second siren, then another 7 seconds before it can sound again. Each time comes from that model's August 2025 PDF, and the EL00002 amazon.co.uk bullets omit the 6 seconds. HERCHR, JUHUTONG and DOUQIFEI print none of these delays. Keep each number on the Defender it was written for.
Should I use the sticky pad on the Ultra Slim?
Use the cord when the handle should set the EL00237 off. The pad is optional, and Defender says it can mark the surface, work as a forced-entry sensor, and reduce handle detection. A buyer who stuck one to glass got no trigger, then tied the unit to the window handle. Tighten the cord so the body cannot fall. The EL00002 hangs on a metal handle, which is a different fitting.
Why does the alarm sound when I switch it off?
Your hand moves the handle as you reach the control, and that movement starts the siren. On the EL00002, amazon.co.uk buyers describe it sounding as they turn the dial to 0. Hang the unit while it is off, wait out its delay, and disarm with as little shake as you can. Neither sheet documents a remote. If it fires before your hand reaches the handle, the sensitivity is already high for this door.
When should a fitter or a locksmith take over?
Call a fitter or a locksmith if this door is the fire exit for someone who wanders at night. Six or seven seconds on the matching Defender sheet is a poor plan for that person, and the siren does not make the door easier to open. Call them too if the window must lock, or if a drill might void the window guarantee. These steps only hang a battery unit on a handle you already use.

Related pages

Alarm versus a lockable handle

Window handle with alarm

Best door handle alarm UK: metal handle or a hotel

UK window handle alarms: sensor, fit and batteries

Hotel door handle alarm to pack when you cannot drill

Sources

Public UK sources and the manufacturer note below. amazon.co.uk listings checked on 15 October 2026.

  1. GOV.UK: Approved Document Q, security in dwellings (retrieved 15 October 2026)
  2. BSI: PAS 24:2022+A1:2024 (retrieved 15 October 2026)
  3. NPSA: security afforded by domestic windows (retrieved 15 October 2026)
  4. ProtectUK: security at home (retrieved 15 October 2026)
  5. Greater Manchester Police: window security (retrieved 15 October 2026)
  6. Sold Secure: ratings (retrieved 15 October 2026)
  7. Secured by Design: Defender Ultra Slim Door Handle Alarm (retrieved 15 October 2026)
  8. Defender: EL00237 instructions (retrieved 15 October 2026)