MC 240-S45 Instruction Manual 4-MC240S45-01
©2013 Alarmtech Rev. MC240S45_1347en Page 2of 2
OPERATING PRINCIPLE
MC 240-S45 magnetic contact has two parts: the contact
part with a reed switch and the magnet part. In its neutral
position the reed switch remains closed under the force of
the magnetic field. Opening the monitored object increases
the distance between the reed switch and the magnet. This
reduces the influence of the magnetic field on the reed
switch until it opens and activates an alarm.
Magnetic contacts should not be installed in the vicinity of
strong magnetic fields.
INSTALLATION
Depending on the application, contact and magnet should
be installed in one of the possible configurations. Installation
drawings show the correct positioning of the contact parts.
Contact and magnet should be installed in parallel, with
plastic plugs corresponding to each other. Offset will reduce
the working distances. The contact should be mounted on
the stationary part of the monitored object (ex. door frame)
and the magnet on the movable part (ex. door leaf).
For sites where it is impossible to mount the contact
directly, aluminium brackets and additional magnet parts are
available. Brackets can be used to mount the contact parts
away from a ferromagnetic surface or to solve problems
with aligning the contact with the magnet. Contact and/or
magnet should be screwed to the oval slots in the brackets
and adjusted to a suitable position.
Only non-ferromagnetic screws may be used for mounting
the contact.
After the installation, use an ohmmeter to check the
electrical connections and test the operation of the
magnetic contact.
Warning: installation in ferromagnetic environment is not
recommended.
INSTALLATION DRAWINGS
MC 240-S45 configurations:
MC 200-71 accessory:
RESISTORS (OPTIONAL)
MC 240-S45 is available in two additional options with
resistors of the chosen value: MC 240-S45-R with one
resistor parallel to the alarm switch and MC 240-S45-2R with
two resistors in 2 EOL configuration (see schematics below).
MC 240-S45-R:
MC 240-S45-2R:
DISTANCE TABLE
