GHM DeltaOHM LPUVA02 User manual

Operating manual
UVA Radiometer
LPUVA02
www.deltaohm.com
English
Keep for future reference.

LPUVA02 - 2 - V2.0
TABLE OF CONTENTS
1 INTRODUZIONE .................................................................................................... 3
2 WORKIN PRINCIPLE ........................................................................................... 4
3 INSTALLATION ..................................................................................................... 5
4 ELECTRICAL CONNECTIONS .................................................................................. 8
4.1 LPUVA02 CONNECTIONS ....................................................................................... 8
4.2 LPUVA02AC CONNECTIONS ................................................................................... 9
4.3 LPUVA02AV CONNECTIONS ................................................................................... 9
5 MEASUREMENT ................................................................................................... 10
5.1 LPUVA02 ...................................................................................................... 10
5.2 LPUVA02AC ................................................................................................... 10
5.3 LPUVA02AV ................................................................................................... 10
6 MAINTENANCE .................................................................................................... 11
7 TECHNICAL SPECIFICATIONS ............................................................................. 12
8 SAFETY INSTRUCTIONS ...................................................................................... 13
9 ACCESSORIES ORDERIN CODES ....................................................................... 14

LPUVA02 - 3 - V2.0
1 INTRODUCTION
The LPUVA02 radiome er measures he global irradiance in he UVA spec ral range
on a fla surface (W/m
2
). Measured irradiance is he resul of he sum of direc solar
irradiance and of diffuse irradiance.
The radiome er can also be used for moni oring indoor UVA emissions.
Available in he following versions:
•LPUVA02: PASSIVE
•LPUVA02AC: ACTIVE wi h 4..20 mA CURRENT ou pu (0…200 W/m
2
)
•LPUVA02AV: ACTIVE wi h 0..1 or 0..5 or 0..10 V VOLTAGE ou pu o be de-
fined when ordering (0…200 W/m
2
).
Each radiome er is individually calibra ed a he fac ory and is dis inguished by i s own
calibra ion fac or. The calibra ion is performed by comparison wi h he primary s and-
ard of he Del a OHM me rology labora ory, using he emission line a 365 nm of a
sui ably fil ered Xe-Hg lamp.
Note: there is no international standard for the calibration of UVA radiometers; there-
fore, when considering the value of the calibration coefficient, the method by which it
was obtained must be taken into account; the same radiometer calibrated with differ-
ent procedures can have different calibration factors

LPUVA02 - 4 - V2.0
2WORKIN PRINCIPLE
LPUVA02 radiome er is based on a solid s a e sensor, he spec ral ma ch wi h he de-
sired curve is ob ained using a special fil er. The rela ive spec ral response is repor ed
on figure 2.1.
Fig. 2.1
The radiome er is provided wi h a 50 mm ex ernal diame er dome in order o supply a
sui able pro ec ion of he sensor o he wea her agen s.
The response in accordance wi h he cosine law has been ob ained hanks o he par-
icular shape of he diffuser and of he housing. The devia ion be ween he heore ical
response and he measured one is shown in he Fig. 2.2.
Angle
Fig. 2.2
The excellen rela ion be ween he response of he radiome er and he cosine law al-
lows using he ins rumen also when he sun has a very low raising ( he UVA diffuse
radia ion increases as he sun moves away from he zeni h, herefore he error on he
direc radia ion, due o he imperfec response according o he cosine law, becomes
negligible on he measuremen of he global radia ion).
Rela ive spec
ral response
% devia ion from heore ica
l response

LPUVA02 - 5 - V2.0
3INSTALLATION
Before ins alling he radiome er, refill he car ridge con aining silica-gel crys als. Silica
gel absorbs humidi y in he dome chamber and preven s, in par icular clima ic condi-
ions, condensa ion on he in ernal walls of he domes and measuremen al era ion.
Do no ouch he silica gel crys als wi h your hands while refilling he car ridge. Carry
ou he following ins ruc ions in an environmen as drier as possible:
1. Loosen he hree screws ha fix he whi e shade disk.
2. Unscrew he silica gel car ridge using a coin.
3. Remove he car ridge perfora ed cap.
4. Open he sache con aining silica gel (supplied wi h he radiome er).
5. Fill he car ridge wi h he silica gel crys als.
6. Close he car ridge wi h i s own cap, paying a en ion ha he sealing O-ring be
properly posi ioned.
7. Screw he car ridge o he radiome er body using a coin.
8. Check ha he car ridge is screwed igh ly (if no , silica gel life will be reduced).
9. Posi ion he shade disk and screw i wi h he screws.
10. The radiome er is ready for use.
The figure below shows he opera ions necessary o fill he car ridge wi h he silica gel
crys als.
Fig. 3.1: filling the silica-gel cartridge
Silica-gel
cartridge
Perforated cap
Sealed s
achet
of silica-gel crystals
Filling Closing the cartridge

LPUVA02 - 6 - V2.0
•The radiome er mus be moun ed in an easy- o-reach loca ion in order o clean he
dome regularly and carry ou main enance. A he same ime, make sure ha no
buildings, cons ruc ions, rees or obs ruc ions exceed he horizon al plane where
he radiome er lies. If his is no possible, selec a si e where obs ruc ions in he
pa h of he sun from sunrise o sunse do no exceed 5 degrees of eleva ion.
•The radiome er mus be loca ed far from any kind of obs ruc ion, which migh re-
flec sunligh (or sun shadow) on o he radiome er i self.
•For fixing, use he holes on he radiome er body (remove he shade disk o access
he holes and reposi ion i af er moun ing) or he sui able accessories (see he fig-
ures below). In order o allow an accura e horizon al posi ioning, he radiome er is
equipped wi h a levelling device: he adjus men is made by means of he wo lev-
elling screws ha allow adjus ing he radiome er inclina ion. The mas heigh does
no exceed he radiome er plane o avoid measuremen errors caused by any re-
flec ion or shadow of he mas i self.
•I is preferably o hermally insula e he radiome er from i s moun ing bracke en-
suring, a he same ime, a good elec rical con ac o ground.
Fig. 3.2: fixing holes and levelling device
Fixing holes ∅ 6 mm
Levelling
device

LPUVA02 - 7 - V2.0
HD2003.79K
HD2003.77C
HD2003.83
HD2003.83.1
HD2003.85K
Fig. 3.3: fixing accessories

LPUVA02 - 8 - V2.0
4ELECTRICAL CONNECTIONS
LPUVA02… has a 4-pole connec or and uses he CPM12AA4... optional cables.
The metallic housing of the radiometer should preferably be
grounded ( ) locally. In this case, do not connect the wire of the
cable corresponding to the housing to prevent ground loops.
Only if it is not possible to ground locally the metallic case of the
radiometer, connect the wire of the cable corresponding to the
housing to ground. No e: in LPUVA02AV he housing is no connec ed
o he connec or.
4.1 LPUVA02 CONNECTIONS
The radiome er LPUVA02 is passive and does no require power supply. I is o be
connec ed ei her o a millivol me er or o a da a acquisi ion sys em. Typically, he ra-
diome er ou pu signal does no exceed 50 mV. In order o be er exploi he radiome-
er fea ures, he readou ins rumen should have 1 µV resolu ion.
Connector Function Color
1 +Vou Red
2 -Vou Blue
3 Housing (C) Whi e
4 Cable shield (SH) Black
12
34
+Vout
-Vout
SH
C
Fig. 4.1: LPUVA02 connections
CPM12AA
4
…
c
a
ble
Radio
me er M12
male connec or
Da alogger or
conver er/amplifier
wi h V or mA ou pu
Connect to ground only if it is not possible to
ground locally the housing of the radiometer

LPUVA02 - 9 - V2.0
4.2 LPUVA02AC CONNECTIONS
The radiome er LPUVA02AC has 4…20 mA ou pu and requires 10…30 Vdc ex ernal
power supply. I is o be connec ed o a power supply and an ins rumen wi h 4…20
mA inpu as shown in fig. 4.2. The load resis ance of he ins rumen reading he signal
mus be ≤ 500 Ω.
Connector Function Color
1 Posi ive (Iin) Red
2 Nega ive (Iou ) Blue
3 Housing (C) Whi e
4 Cable shield (SH) Black
4...20 mA
12
34SH
Iin
Iout
C
Fig. 4.2: LPUVA02AC connections
4.3 LPUVA02AV CONNECTIONS
The radiome er LPUVA02AV has 0…1 V, 0…5 V or 0…10 V ou pu (depending on he
ordered ou pu ) and requires ex ernal power supply: 10…30 Vdc for 0…1 V and
0…5 V ou pu s, 15…30 Vdc for 0…10 V ou pu . I is o be connec ed o a power sup-
ply and an ins rumen wi h vol age inpu as shown in fig. 4.3. The load resis ance of
he ins rumen reading he signal mus be ≥ 100 kΩ.
Connector Function Color
1 Ou pu posi ive (+Vou ) Red
2 Ou pu nega ive
Power supply nega ive (GND) Blue
3 Power supply posi ive (+Vdc) Whi e
4 Cable shield (SH) Black
12
34
SH
GND
+Vdc
+Vout
Fig. 4.3: LPUVA02AV connections
CPM12AA
4
…
c
a
ble
Radio
me er M12
male connec or
Power supply
Connect to ground only if it is not possible to
ground locally the housing of the radiometer
Ins rumen wi h
4…20 mA inpu
CPM12AA
4
…
c
a
ble
Radio
me er M12
male connec or
Power supply
Ins rumen
wi h
vol age inpu

LPUVA02 - 10 - V2.0
5MEASUREMENT
Below are he ways o calcula e he irradiance.
5.1 LPUVA02
Each radiome er is dis inguished by i s own sensi ivi y (or calibra ion fac or) S ex-
pressed in µV/(Wm
-2
) and shown in he label on he radiome er (and in he calibra ion
repor ).
The irradiance E
e
is ob ained by measuring wi h a mul ime er he difference of po en ial
DDP a he ends of he sensor and applying he following formula:
E
e
= DDP / S
where:
E
e
is he irradiance expressed in W/m
2
;
DDP is he difference of po en ial expressed in µV measured by he mul ime er;
S is he sensi ivi y of he radiome er expressed in µV/(Wm
-2
).
5.2 LPUVA02AC
The 4…20 mA ou pu signal corresponds o 0…200 W/m
2
irradiance range.
The irradiance E
e
is ob ained by measuring wi h a mul ime er he curren I
out
absorbed
by he sensor and applying he following formula:
E
e
= 12.5
•
(I
out
– 4mA)
where:
E
e
is he irradiance expressed in W/m
2
;
I
out
is he curren expressed in mA absorbed by he radiome er.
5.3 LPUVA02AV
The ou pu signal (0…1 V, 0…5 V or 0…10 V depending on he version) corresponds o
0…200 W/m
2
irradiance range.
The irradiance E
e
is ob ained by measuring wi h a mul ime er he ou pu vol age V
out
of
he sensor and applying he following formula:
E
e
= 200
•
V
out
for he version 0…1 V
E
e
= 40
•
V
out
for he version 0…5 V
E
e
= 20
•
V
out
for he version 0…10 V
where:
E
e
is he irradiance expressed in W/m
2
;
V
out
is he ou pu vol age expressed in V measured by he mul ime er.