Monitored vs unmonitored magnetic locks: what is the difference?
When choosing a magnetic lock for an access control system, you will often see models described as monitored or unmonitored. Some versions also include a door status output or LED indication.
These features provide different information about the door and locking system. Choosing the right combination depends on what your access control equipment needs to monitor.
This guide explains the differences between lock status monitoring, door status outputs and LED indication, and what to check before choosing a magnetic lock.
What is a magnetic lock?
A magnetic lock, commonly called a maglock, uses an electromagnet and an armature plate to hold a door closed while power is applied.
The electromagnet is normally mounted to the door frame, with the armature plate attached to the door. When correctly installed, aligned and powered, the two parts form a magnetic bond.
Magnetic locks operate on a fail-safe basis. When power is removed, the magnetic bond releases.
They are commonly used with:
- Access control systems
- Keypads
- Proximity readers
- Door entry systems
- Intercom systems
- Press to exit buttons
- Emergency door release units
What is an unmonitored magnetic lock?
An unmonitored magnetic lock provides electromagnetic locking without a lock status monitoring output.
It holds the door closed while powered, but does not provide an electrical signal confirming that the magnetic bond has been established.
An unmonitored model may be suitable where the system needs to control the lock without receiving feedback about its locking condition.
However, an unmonitored magnetic lock can still be available with a separate door status output.
What is a monitored magnetic lock?
A monitored magnetic lock includes a lock status monitoring output.
This provides compatible equipment with feedback about the magnetic bond between the electromagnet and armature plate.
Depending on the lock and connected controller, the output can be used for:
- Lock status displays
- Security monitoring
- Alerts when the expected locking condition is not achieved
- Integration with door management systems
The controller must support the monitoring output and be configured to use it.
What is the main difference between monitored and unmonitored magnetic locks?
The main difference is whether the lock provides feedback about its magnetic locking condition.
A monitored magnetic lock includes a lock status monitoring output.
An unmonitored magnetic lock does not include a lock status monitoring output.
Monitoring does not increase holding force. Monitored and unmonitored versions within the same range may provide the same holding force.
The choice depends on the feedback required by the connected system.
What is a door status output?
A door status output provides a signal indicating whether the door is open or closed.
This is separate from lock status monitoring.
A door can be closed without being magnetically locked. For example, the door may be resting against the frame while power to the magnetic lock is switched off.
Door status monitoring can be useful for:
- Door position displays
- Door-held-open alerts
- Door-forced-open alerts
- Access event monitoring
- Door interlock systems
These functions depend on the connected controller and its configuration.
What is the difference between lock status and door status?
Lock status monitoring provides feedback about the magnetic bond.
Door status monitoring provides feedback about whether the door is open or closed.
The two functions answer different questions:
- Has the magnetic locking condition been achieved?
- Is the door open or closed?
Where both types of information are required, choose a suitable monitored magnetic lock with a door status output, or use an appropriate separate door contact alongside lock monitoring.
What does DS or DSU mean?
Within the magnetic lock ranges covered here, DS or DSU identifies versions with a door status output.
For example, the U10001 is an unmonitored magnetic lock, while the U10001DSU adds a door status output.
Both remain unmonitored for lock status.
Always check the individual product specification, as model suffixes and available functions can vary between manufacturers and ranges.
Can an unmonitored magnetic lock have a door status output?
Yes. An unmonitored magnetic lock can include a door status output without providing lock status monitoring.
A product range may therefore offer:
- An unmonitored magnetic lock without a door status output
- An unmonitored magnetic lock with a door status output
The additional output reports the door position. It does not confirm the magnetic bond.
This distinction is useful when comparing standard models with DS or DSU versions.
What does the LED on a magnetic lock indicate?
An LED provides a local visual indication. Its function depends on the particular magnetic lock.
Where a product specifies a lock status LED, the indication relates to lock status.
For models specified with green unlocked and red locked indication:
- Green indicates unlocked
- Red indicates locked
This should not be described as door status indication.
Always check the product specification to confirm the LED function and colour sequence.
Does an LED mean the magnetic lock has a monitoring output?
An LED alone does not confirm which electrical monitoring outputs are available.
A visual indicator and a monitoring output serve different purposes:
- The LED provides a local indication at the lock
- The monitoring output sends a signal to compatible equipment
Check the specification for lock monitoring, door status output and LED indication separately.
When should you choose a monitored magnetic lock?
A monitored magnetic lock may be suitable where the connected equipment needs feedback about the magnetic locking condition.
Typical applications include:
- Commercial access control systems
- Security monitoring stations
- Door management systems
- Restricted access areas
- Installations requiring lock status feedback
Check that the controller has suitable inputs and can use the monitoring information.
Installing a monitored lock alone does not automatically create an alarm or status display.
When should you choose an unmonitored magnetic lock?
An unmonitored magnetic lock may be suitable where the installation requires electromagnetic locking without lock status feedback.
This can include systems where:
- The controller only needs to switch power to the lock
- Lock status monitoring is not required
- Door position is monitored separately
- A door status version provides the feedback needed
Choose according to the system requirements and the functions that will actually be connected.
Can a separate door contact be used?
A compatible separate door contact can provide door position feedback where required.
This may be useful when the selected magnetic lock does not include a door status output, or where a separate sensing arrangement is preferred.
A door contact indicates whether the door is open or closed.
It does not replace a magnetic lock’s lock status monitoring output.
What should you check before ordering?
Before choosing a monitored or unmonitored magnetic lock, check:
- Required holding force
- Single or double-door arrangement
- Operating voltage
- Current draw
- Lock status monitoring requirements
- Door status output requirements
- LED indication requirements
- Controller input compatibility
- Door material and frame construction
- Mounting space
- Compatible brackets and accessories
- Cable requirements
- Internal or external installation requirements
- Fire door requirements
- Emergency release arrangements
For fire doors and escape routes, the lock, mounting method and associated equipment must be suitable for the complete door application.
Monitoring features alone do not establish that suitability.
Summary
Monitored and unmonitored magnetic locks provide electromagnetic door locking, but offer different feedback functions.
A monitored magnetic lock includes a lock status monitoring output. An unmonitored magnetic lock does not provide this output.
A door status output reports whether the door is open or closed. It can be included on an unmonitored model without making it a lock-monitored magnetic lock.
LED indication is another feature to check separately, as its purpose depends on the model.
Choosing the right magnetic lock means checking the locking requirements, monitoring functions and connected equipment together.
You can find our range of magnetic locks here - https://www.smartaccesssolutions.uk/pages/magnetic-locks