Danfoss Devireg 850 Operating guide

GB-DAS

Installation and user manual

Devireg™ 850 sensor

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Table of content

1 Sensors and control zones		3
1.1	Sensor types and function	3
1.2	Control zones	4
1.3	Assign sensors to control zones	5
2 Placing and installation of sensors		6
2.1	Placing ground sensors	6
2.1.1	Placing the first ground sensor in a zone	6
2.1.2	Placing the following ground sensors in a zone	6
2.1.3	Example with ground sensors	7
2.1.4	Extending the ground sensor cable	7
2.2	Installing ground sensors	8
2.3	Placing roof sensors	10
2.3.1	Placing the first roof sensor in a zone	10
2.3.2	Placing the following roof sensors in a zone	10
2.3.3	Guiding plates	10
2.3.4	Example with roof sensors	11
2.3.5	Extending the roof sensor cable	11
2.4	Installing roof sensors	12
3 Technical specification		13
4 Appendix A – PSU & feeder cable		14

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1 Sensors and control zones

This section guides you through a short introduction to the terms used in the manual

-Area type

-Sensor type

-Controller

-Control Zones

Finally you will be able to assign a number of sensors to the chosen control zones.

1.1 Sensor types and function

Identify the type(s) of area prepared for the DEVI ice and snow melting system, by looking fig. below:

	3
	4	2
S	W
E	N
		1

1.Walkways and parking areas

2.Steps and stairs

3.Roofs and roof edges

4.Gutters and down pipes

For ground areas like 1 and 2 you have one or more ground sensors.

For roof areas like 3 and 4 you have one or more roof sensors.

The ground and roof sensors both measure­ two things on the sensor surface

-temperature

-moisture from ice, snow, hail or rain

These measurements are input to the Devireg 850, and it decides how the ice and snow melting system­ should control the heated areas.

Details about the setup of the controller­ can be found in the Devireg 850 installation­ manual.

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1 Sensors and control zones

1.2 Control zones

A Devireg 850 and up to 4 sensors are able to control an area as a single zone, but can also control more areas as 2 separated control zones.

2 control zones consits of minimum 2 heating elements + 2-4 sensors and can be:

Combi zones	=	when you have both a roof and a ground area
Dual zones	=	e.g. if steps should have a better performance than a walkway

If the power supply is limited, both combi and dual zones gives you the possibility to prioritize which zone to operate first.

A Devireg 850 and up to 4 sensors give the following 5 control options:

Zone type

Single zone ground	1-4 in one zone
Single zone roof	1-4 in one zone
Combi zones	1-3 in one ground zone 1-3 in one roof zone
Dual zones ground	2-4 split in two zones
Dual zones roof	2-4 split in two zones

Maximum 4 sensors in all

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1 Sensors and control zones

1.3 Assign sensors to control zones

There are some good reasons to have 2 or more sensors in one control zone.

-Higher degree of detection safety, which is relevant for larger, complex or busy roof and ground areas.

-Approx. 1 hour faster ground system, as one sensor measures the ground temperature and other ­sensors measure the moisture whereas a single sensor must switch ­between temperature and moisture ­measurements.

Now decide how the ice and snow melting system should be operated and assign the sensors to the control zones. In case of questions the system designer must be consulted.

Draw circles around
Zone type and
1-4 Sensors
Single zone ground	x	1	2	3	4
Single zone roof	x					1	2	3	4	Maximum 4
Combi zones	x	1	2	3		1	2	3
										sensors in all
Dual zones ground	x		2	3	4
Dual zones roof	x						2	3	4

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2 Placing and installation of sensors

At this point you must have identified and assigned sensors to the control zones as prescribed in section 1.

In this section 2 you will be guided through a correct placing and installation of the sensors. For placing and installation of ground sensors see section 2.1.

For placing and installation of roof ­sensors see section 2.2.

2.1 Placing ground sensors

Placing ground sensors in appropriate spots is very important for the performance of the ice and snow melting system. The appropriate spot must fulfill some characteristics, where the below 2 are the most important:

The sensors must be placed minimum 1 meter within the boundaries of the heated zone The sensors must not be covered or prevented from being exposed to snow or rain.

This includes dirt, leaves and pebbles.

2.1.1 Placing the first ground sensor in a zone

Find one who knows the area and make him describe the area function and weather conditions. The first ground sensor in a zone must now be placed where the first snow appears. The appropriate spot can be found by following below steps.

a)Where the heated area is in shade all day. Look e.g. for algae.

b)Where e.g. a wind shield make the snow drift

c)Where the most traffic from shoes or car wheels happens

If you have a dual zone system, the first sensor for the other zone must be placed by following the same steps above.

2.1.2 Placing the following ground sensors in a zone

The following ground sensors in a zone must be placed where the surface dries up last. The appropriate spot can be found by following below steps.

d)Where the heated area is in shade all day

e)Where the melting water accumulates e.g. due to hollows in the area

f)So the whole zone is covered, but min. 1 meter from other sensors

If there is doubt about the appropriate spot, prepare a second spot for later use.

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