LPSD18 - 3 - V1.6
1INTRODUCTION
Th Sunshin Duration s nsor LPSD18 m asur s status and sunshin duration. Th
WMO (World M t orological Organization) d fin s th sunshin duration as th tim
during which th dir ct solar radiation xc ds th l v l of 120 W/m2.
Th radiation m asur m nt is p rform d with an array of photodiod s arrang d in a
particular g om try which allows to obtain an accurat m asur m nt in any w ath r
conditions. This solution avoids th us of m chanical moving parts and nsur s high
r liability ov r tim .
Th instrum nt, b sid s indicating th pr s nc of sun as r quir d by th WMO,
m asur s also dir ct radiation (SRD), th r for it can b us d as a low cost alt rna-
tiv to a pyrh liom t r, which us is bound to a solar track r.
LPSD18 is quipp d with a h ating l m nt s parat ly pow r d and galvanically iso-
lat d, which pr v nts th formation of cond nsation on th glass surfac onto which
th s nsitiv l m nts ar plac d. For harsh climat s, th abov -m ntion d v rsions
ar availabl with a s cond h ating l m nt (option R, LPSD18.xR), which pr v nts
th formation of ic and pr v nts snow from s ttling.
Th instrum nt is availabl in thr v rsions, which diff r in th typ of output:
OUTPUT
Heating
Model RS 85
Modbus-RTU
SDI-12 Voltage-free
contact
Analog
0…1 V
Digital
voltage
LPSD18.1[R] √ √
With option R
in th cod
LPSD18.2[R] √ √ √
LPSD18.3[R] √ √
Voltage-free contact: clos d SRD ≥ 120 W/m2, op n SRD < 120 W/m2
Analog output: 0…1 V 0…2000 W/m2
Digital voltage output: 1V SRD ≥ 120 W/m2, 0V SRD < 120 W/m2
Th instrum nt do s not n d any positioning adjustm nt during th y ar and it can
b install d on a mast or plac d on a flat bas using prop r fixing optional acc sso-
ri s.
Th application fi lds ar multipl : from th agronomy (agricultural sci nc ) to th
study th growth of crops, to photovoltaic syst ms for v rifying th ir p rformanc , to
building automations for automatic op ning/closing of blinds, shutt rs and, in g n ral,
to all thos ar as wh r it is n c ssary to monitor th pr s nc of sunlight.
