Carmanah M650H User Manual page 75

RANGE (NM) EFFECTIVE INTENSITY (cd)
T = 0.74
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5.0
5.1
5.2
5.3
5.4 102
5.5 109
5.6 116
5.7 124
5.8 132
5.9 141
6.0 150
6.1 160
6.2 171
6.3 181
6.4 193
6.5 205
6.6 218
6.7 232
6.8 246
6.9 261
7.0 277
75
T = 0.85
46 26
50 27
54 29
58 31
62 33
67 34
72 37
77 39
83 41
89 43
95 46
48
51
53
56
59
62
65
69
72
76
80
83
87
91
96
100
105
© 2014, Carmanah Technologies Corporation. June 2014. 61249_M650H_User_Manual_RevC
Effective Intensity
The effective intensity of a flashing lantern comes
from the following calculation known as Schmidt-
Clausen or Blondel-Rey documented in IALA
Recommendations E-122 (2001) and E-200-4
(2008). This method is valid for the rectangular,
non-fluctuating flash profiles below the flicker fusion
frequency (60 Hz) used by Carmanah lanterns.
I x F
I
= p
e
C + F
I = effective intensity (cd)
e
I = peak intensity (cd)
p
C = visual time constant (s)
F = flash duration (s)
The visual time constant is 0.2 s for a lantern at night-
time.
M650H USER MANUAL