Danfoss DEVIreg 850, Installation And User Manual

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DEVIreg™ 850 ground and roof sensors
Installation and user manual 7
2 .1 .3 Example with ground sensors
1 2 3
1 2 3
1 2 3
In this example a lower step section (1), a
walkway platform (2) and an upper step
section (3) is heated. Depending on number of
zones and detection safety, 2-3 ground sensors
is installed.
Sensor no. 1 is the most important as this is
placed where snow is likely to appear first due
to shade and snow drift also because the spot
is stepped on by pedestrians.
Sensor no. 2
is also important as the platform
is object to water puddles. Here the shaded
spot will dry up last. If the power supply is lim-
ited, the platform could be a low priority zone
in a dual zone system.
Sensor no. 3 is relevant if more detection
safety is required, as additional to sensor no. 1.
Can be prepared for later installation.
2 .1 .4 Extending the ground sensor cable
The ground sensor consists of two parts, a sensor part with a sensor cable and a sensor
tube.
A 15-meter cable is supplied with the sensor part. Approx.
0.5 m of this cable should be coiled inside the bottom of the
sensor tube, leaving 14.5 meter to be connected with the
DEVIreg™ 850 controller.
If the appropriate spot is located out of this range, a feeder
cable extension for the sensor may be needed. This sensor
cable extension must be a 4-wired cable with a diameter in accordance with the table in
Appendix A – Sensor cable extension.
Note each new colour of the 4 wire cable feeder extensions (white, white, red and
black) . Dual zone sensors: Do NOT join feeder cable extensions from separate
zones .