Irradian PR450 Instruction Manual

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Handbook Ref No. MH096/Issue G
File Ref: PR450_G.doc

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   1 Introduction
2 Specification
3 Operation
4 Irradiance Measurements
5 Cosine Angular Response
6 Calibration Description
7 Care and Maintenance
8 Optional Accessories
9 Block Diagram
10 Environmental Care, Recycling and Disposal

PR450 Phototherapy Radiometer Irradian Limited
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The Irradian portable phototherapy radiometer model PR450 is designed
specifically to measure directly the irradiance of blue light for the
treatment of hyperbilirubinaemia in new born babies.
The photodiode and colour glass filters are designed to give a spectral
response closely matching the bilirubin phototherapy action spectrum.
Good blocking of the detectors response outside the bandpass ensures
the radiometer does not measure non-therapeutic light. The cosine
corrected diffuser input ensures accurate measurements where ever the
light source.
Note: The PR450 is NOT an ultra violet radiometer and should NOT be
use to measure the output of ultra violet lamps in UV phototherapy
treatment.

Irradian Limited PR450 Phototherapy Radiometer
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RADIOMETER
Range: 0 - 199.99 µW/cm²/nm
Monochromatic Cal. The radiometer with detector / filter is
calibrated with a 450nm monochromatic
source.
Spectroradiometric Cal. The radiometer with detector / filter is
calibrated to match the measurement of a
spectroradiometer for a particular source,
e.g. phototherapy halogen lamp or photo-
therapy fluorescent lamp.
Accuracy Absolute calibration accuracy ±7.5% traceable to
NPL standards.
DISPLAY UNIT PR450X
Controller: 80C51 based 8bit micro-processor with a
3.6864MHz clock.
Memory On board non volatile RAM for calibration
factors and set-up parameters.
Integration Time 0.33s.
Conversion Scale 17 bit.
Conversion Accuracy: Measurement accuracy ±1digit with a
linearity error of <1%.
Display: 4½ digit lcd display. Character height 10mm.
Power Supply: 9 volt 1200mAh, PP3 battery.
Power Consumption: Shut down mode <5µA.
Operating 10 - 20mA.
Battery Life ~ 50 hours.

PR450 Phototherapy Radiometer Irradian Limited
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Temperature Range: 0 to 40°C. 80% RH.
Dimensions: 150 x 80 x 45mm.
High impact polystyrene.
Weight: Approximately 270g.
Front Panel Controls:
ZERO Initiates a zero or background measurement
Routine.
HOLD/RUN Display is held at present reading until HOLD
button is pressed again.
 Power on / off button.
Connector: 8 pin mini DIN type detector connector.
6 pin mini DIN type RS232 connector for factory use only.

Irradian Limited PR450 Phototherapy Radiometer
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DET201450 DETECTOR
Amplifier PCB Photodiode
Cable
Glass Filters
Cosine Diffuser
The DET201450 detector comprises of an aluminium housing,
photodiode, R450 filter and PCB assembly.
Detector: 5.2 mm² High stability GaAsP photodiode.
Spectral Response: Refer Figure 1.
Angular Response: Accurately cosine corrected to Lambert's
Cosine Law. Maximum error is less than ±5%
from true response to 70° from normal
incidence, reference Section 5.
Temperature Coefficient: <0.3 %/°C.
Amplifier Gain 5x10
5
V/A.
Current to Frequency 0 - 0.5Mhz.
Linearity Error: <1% across range.
Temperature Range: Operation: -10 to +60°C.
Storage: -20 to +70°C.
Detector Housing: Black anodised aluminium alloy housing.
Cable: 1 metre cable to 8 pin mini DIN type connector.
Weight: Approximately 140g.

PR450 Phototherapy Radiometer Irradian Limited
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DET201450 Detector
Typical Spectral response
0
10
20
30
40
50
60
70
80
90
100
400 415 430 445 460 475 490 505 520 535 550
R
e
s
p
o
n
s
e
%
Wavelength (nm)
Figure 1

Irradian Limited PR450 Phototherapy Radiometer
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SETTING UP
1) With the unit OFF, plug the detector 4 way connector into the socket
on the top of the display unit.
2) Press and release the power switch on the PR450 display key pad.
The microcontroller will initiate, the display momentarily showing:-
The radiometer display will now change to show the units value. A
typical display is shown below.
3) It is recommended that the radiometer amplifier is nulled periodically.
Place the cover over the detector. Press and release the ZERO switch,
the display will momentarily show:-
4) The micro controller will now measure the amplifier offset and store
this value in the non volatile memory. All subsequent measurements
will first have this offset subtracted before displaying the
measurement.
At the end of the sequence the display will show:-
5) Remove the light cover from the detector. The equipment is now ready
for use.
6) At any time the measurement process can be halted by pressing the
HOLD/RUN button. Pressing the button once again will resume the
measurement process.