Operating instructions
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• You can attach several external sensors to the door/window contact sensor, such as when
you have a wide window bank with several windows/doors.
These external contacts must be NC (normally closed) contacts.
When connecting several external NC contacts, they must be connected in series. See
figure 14.
NC contacts
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Figure 14
Do not connect terminating resistors!
• The maximum attainable wiring length is greatly dependent upon the cable used and the
transmission resistance of the NC contacts. Under ideal circumstances a wiring length of
100m or more is possible.
• When installing the door/window contact sensor and magnet on metal doors or windows the
wireless range may be reduced.
• As a rule, the magnet is mounted on the moving part (window or door, for example) and the
‘FHT80TF-2’ door/window contact sensor is attached to the static part (window or door
frame). Please observe the recommended distances between the magnet and the door/
window contact that are illustrated in figure 13 on the previous page.
Our tip:
Before using screws to mount the device, you should first check that it is working
properly so as to avoid drilling any unattractive holes in the ‘wrong’ location.