- 48 -
Measurements of the signal by oscilloscope
In the drawing below, the points where to connect
the oscilloscope are shown:
Point
B
shows the quality
of the signal received
In the graphic here below the wave shapes concerning the signal quality are shown:
1-
the beam is in quiet condition and there is no passage of people or any perturbation due to
moving objects, the level is fix . Check that the quiet condition is as described.
2-
the beam is disturbed or we are crossing a sensitive area (partial darkening)
3-
the beam has been darkened and there is an alarm situation
Point
C
shows the alarm
threshold (trimmer sens.).
In this case the sensitivity
is adjusted at the half
C
B
.2 s
0.5 V
.2 s
0.5 V
.2 s
2
.1 V DC
x
10
3
.1 V DC
x
10
0 V
Sensitivity
range
Punto A
(ss)
Indicates the range
of the received
signal
Punto C
(SO)
Indicates the alarm
threshold
T
A
M
P
E
R
LEVEL
S
E
N
S
.
C
O
M
P
.
SW1
SW2
T
P
1
B
F
F
T
A
M
P
E
R
T
T
C
N
C
A
U
X
DB
DA
L
E
D
R
O
S
S
O
L
E
D
V
E
R
D
E
8
ON
ON
USB
SI
SS
SO
Punto B
(SI)
Indicates the quality
of the received
signal
E
N
G
GREEN
LED
RED
LED
