Datasheet Content
PHOTOTUBES
TYPE UV1 UV2 UV3
FLAME SENSOR FOR GAS BURNER INTRODUCTION
Flame detection in burners occurs by means of sensors
detecting the presence of flame through an electrical
signal, which can be used by ignition and control devices.
UV phototubes exploit ultra-violet radiation emitted by the
light generated by the flame; they are especially suitable
for appliances in which very dissimilar fuels (e.g. liquid and
gaseous fuels) are used.
UV1 FEATURES
These sensors are used for flame detection in gas and
mixed fuel (gas and oil) burners. UV phototubes consist of
a glass bulb filled with gas, containing two electrodes
suitably shaped. When supplying both electrodes with AC
voltage, if an ultra-violet electromagnetic radiation (range
from 190 to 290 nm) hits the phototube, the electrons,
emitted by the negative biased electrode and captured by
the positive biased one, start an ionization process leading
to the generation of an electric discharge and hence to the
UV2 production of electric current.
UV1, UV2 and UV3 are the available phototube models;
their features and dimensions are explained below.
PHOTOTUBE TYPE UV1
Phototubes type UV1 are available in different sensitivity:
- Standard sensitivity
- /A : medium sensitivity
- /H : high sensitivity
UV3 The standard cable length is 655 mm, but versions with
longer cables are available.
Ø22
85
PHOTOTUBE TYPE UV2
Phototube type UV2 are smaller than phototube type UV1
(the length and the diameter of the case are smaller).
The standard cable length is 655 mm, but versions with
longer cables are available.
Ø17
76
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PHOTOTUBE TYPE UV3 CONNECTION
The length and the superficial treatment of the case are The blue wire is marked with number 8 because it must be
the differences between the UV3 and UV1 models. The connected to terminal 8 in Brahma devices series MF2,
case’s superficial treatment consists of a chromium MF2.4, SR3/TR and M300 and to terminal 21 in Brahma
plating. device type MPI; Brown wire must be connected to the
The UV3 phototube has no cable which is supplied as an earth.
accessory (see fig. 1). In Brahma device type RE3 the blue wire must be
Models different for the sensitivity are available upon connected to the terminal number 3 and the brown wire to
request: the terminal number 4.
- Standard sensitivity
- /A : medium sensitivity DIRECTIONS FOR INSTALLATION
- /H : high sensitivity - Respect the applicable national and European
standards EN 60335-1 and EN 60335-2-102 related to
the electrical safety;
Ø22 - Avoid placing detection cable close to power and
ignition cables;
- In order to avoid problems due to the obsolescence of
the detecting element , we recommend replacing it
80 after about 10.000 operating hours. These flame
sensors are not sensitive to the daylight, therefore if
they are near to neon glow lamps or similar they need
of particular screening for not to be influenced.
- Avoid subjecting the device to strong stress, impacts
or falls
TECHNICAL DATA
Fig. 1 Nominal life time: 10.000 hours (*)
Maximum distance from UV source: 1m
UV1-3 sensor temperature range: -20 ÷ +50 °C (*)
UV2 sensor temperature range: -20 ÷ +60 °C
The Fig. 2 shows the UV1, UV2 and UV3 drilling plane.
(*) UV1 and UV3 phototubes can operating also at
temperature higher than + 50°C, in this case the se nsor life
Per UV1 e UV3 Per UV2 time will be less than the 10.000 nominal hours.
22.5
17.5
REPLACING THE SENSING ELEMENT IN
PHOTOTUBES TYPE UV1 AND UV3:
In these types of phototubes, the sensing element can be
18.5 18.5 17 17 replaced by simply pulling it out of the casing top opening.
37 34 The new sensing element should be inserted into the
Fig. 2 casing in the direction shown in the following figure:
Phototube
insertion direction
Window
ATTENTION -> Company Brahma S.p.A. declines any responsibility for any damage resulting from the Customer’s interfering with the device
BRAHMA SpA
Via del Pontiere,31
37045 Legnago (Vr)
Tel. +39 0442 635211 – Telefax +39 0442 25683 2010/12/23 Subject to amendments without notice
http:// www.brahma.it
E – mail: brahma @ brahma.it
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