Metering Unit - Stihl SR 420 Instruction Manual

10 Metering Unit

K
T = Quantity of active ingredient in liters
W
K K = Concentration in %
T = Required quantity of solution in liters
B
Example:
The calculated quantity of active ingredient is
0.144 liters. According to the maker's instruc‐
tions, the concentration is 0.1%.
Quantity of solution:
0.144 l x 100 = 144 l
0.1 %
9.4 Determining walking speed
Carry out a trial run with the machine fueled and
the container filled with water. Operate the spray
tube (swing it back and forth) as for the real run
described below. Determine the distance walked
in one minute.
Also use the trial run to check the selected work‐
ing width. The best working width for low-growing
crops is 4–5 m. Mark the working width with
stakes.
Dividing the distance walked in meters by the
time in minutes gives you the walking speed in
meters per minute (m/min).
Example:
The distance covered in one minute is 10
meters.
Walking speed:
10 m = 10 m/min
1 min
9.5 Determining discharge rate
The setting of the metering unit is calculated as
follows:
V (l) x v (m/min) x b(m)
a b
2
A (m )
V = Quantity of solution
a
v = Walking speed
b
V = Discharge rate
c
b = Working width
A = Area
Example:
0458-372-0121-C
The values determined above and a working
width of 4 meters require the following setting on
the metering unit:
144 l x 10 (m/min) x 4 m
3600 m
Hectares (ha) have to be converted into m
10,000 = m
To adjust the required discharge rate see "Meter‐
ing Unit".
10 Metering Unit
10.1
► The stop cock (1) is closed when the lever is
► The stop cock (1) is open when the lever is
► Adjust the discharge rate with the metering
= V (l/min)
c
2
2
).
Stop cock
upright.
parallel to the hose.
knob – not the stop cock.
English
= 1.6 l/min
2
(ha x
15