16.1 Determining the collector row clearance z
At sunrise and sunset (when the sun is very low), shading cannot be
avoided when collectors are arranged behind one another. To keep
the reduction in yield within acceptable parameters, observe specific
row clearances (dimension z) in accordance with VDI
guideline 6002-1. When the sun is at its highest on the shortest day of
the year (21/12), the rows at the back should be free of shading.
The angle of the sun β (at midday) on 21/12 must be used to calculate
the row clearance.
In Germany, this angle lies between 11.5° (Flensburg) and 19.5° (Kon-
stanz), subject to latitude.
sin (180° – (α + β))
z
h
=
sinβ
z
h
h
β
α
α
z = Distance between collector rows
h = Collector height (for dimensions see chapter "Specification" for
the relevant collector)
α = Angle of collector inclination
β = Angle of the sun
Example:
Würzburg is approximately located on latitude 50° north.
In the northern hemisphere, this value is deducted from a fixed angle
of 66.5°:
Angle β = 66.5° − 50° = 16.5°
Example with Vitosol-F, type SH
h = 1056 mm
α = 45°
β = 16.5°
1056 mm · sin (180°– 61.5°)
h · sin (180°– (α+β))
sin β
z =
sin 16.5°
z = 3268 mm
z =
α
Clearance between collector rows z in mm
Vitosol-F
Vitosol 200-T,
type SP2A
Vitosol 200-T,
type SPE
Type SV
Type SH
Vitosol 300-T,
type SP3B
Flensburg
25°
6890
3060
6686
—
30°
7630
5715
7448
7511
35°
8370
3720
8154
—
45°
9600
4260
9373
9453
50°
10100
4490
9878
—
60°
10890
4830
10660
10750
Kassel
25°
5830
2590
5446
—
30°
6385
2845
5981
6032
35°
6940
3100
6471
—
45°
7840
3480
7299
7360
50°
8190
3640
7631
—
60°
8720
3870
8119
8187
Munich
25°
5160
2290
4862
—
30°
5595
2485
5290
5772
35°
6030
2680
5677
—
45°
6710
2980
6321
6993
50°
6980
3100
6571
—
60°
7350
3260
6921
7737
16.2 Vitosol-F flat-plate collectors (on supports)
Observe the information on securing collectors on page 111.
Viessmann offers two collector supports for fixing the collectors:
■ With a
variable angle of inclination
(snow loads up to
2.55 kN/m
2
, wind speeds up to 150 km/h):
The collector supports are pre-assembled. They consist of the base
rail, collector support and adjustable support with holes for adjusting
the angle of inclination (see the following chapter).
■ With
fixed angles of inclination
of 30°, 45° and 60° (snow loads up
to 1.5 kN/m
2
, wind speeds up to 150 km/h):
Collector supports with footplates (see from page 131).
For this version the angle of inclination is calculated from the dis-
tance between the footplates.
Cross braces are required for 1 to 6 collectors connected side by side
to secure the support.
Design information on flat roof installation
128
VIESMANN
VITOSOL
16
5822 440 GB