IST-2255.CB01.01
Istruzione / User’s Manual / Manuel d’utilisation
Pag.5/11
TECNOCONTROL S.r.l. Via Miglioli 47 SEGRATE ( MI )
Tel. +39 02 26922890 - Fax +39 02 2133734
When a fuel does not burn properly an excess of CO is produced, which is poisonous. When CO enters the body, it
prevents the blood from bringing oxygen to cells, tissues, and organs.
Petrol (
Gasoline
)
is a liquid mixture of paraffin hydrocarbons (hexane and octane) in proportion very varying and
other additives. The Petrol (
Gasoline
) is volatile and produces extremely inflammable
vapours
, is heavier than air
(middly it has density relative to the air of 2.8 and its LEL is around 1.2%v/v (
express in % Volume
).
OPERATIONAL DESCRIPTION
The two electrochemical sensors are temperature compensated, but are sensitive to extreme humidity variations.
The calibration is carried out with CO gas and for Petrol Vapours. Anyway, it can contemporaneously detect other
gases that should be present in the same environment as listed in
table 4
.
P
REHEATING
: when powered, both the sensors needs a time of preliminary heating of about 60 seconds. During
this period the two yellow LED “
FAULT
” flashes. After this period, the two yellow LED lights off, the green LED “
ON
”
illuminates to indicate normal functioning. After this period the unit is able to detect gasses even if it attains the
optimum stability conditions after about 4 hours continual functioning.
N
ORMAL OPERATION
: the green LED “ON” should be light on.
The Red LED
(
ALARM S1
) illuminates when CO concentration attains 150 ppm.
The Red LED
(
ALARM S2
) illuminates when Petrol Vapours concentration attains 10%LIE.
F
AULTS
:
the instrument signal different kind of failures, as listed below. The Yellow LED,
FAULT S1
or
FAULT S2
illuminates and the "
S1
" CO output or “
S2
” Petrol Vapours Output, falls down to 0 mA.
If a Yellow LED illuminates each 4 seconds (
with Green LED activate
):
this happens when the corresponding
“
Cartridge Sensor
” has exceeded its theoretical period of life and its correct operation is not longer guaranteed. The
detector keeps on operating normally but it is necessary to replace, as soon as possible, the corresponding
“
Cartridge Sensor
” with a new one. The type to be required is described at
Page 1
. The replacement procedure is
described in the attached manual.
If a Yellow LED activate and Green LED is off (
0 mA output signal
):
this signal different kind of faults.
1)
The
corresponding “
Cartridge Sensor
” is not working, please replace with new one.
2)
If a new “
Cartridge Sensor
” is
installed or it is not correctly connected or a not compatible one is mounted. Please check the cartridge
connections and compatibility (
see Table 3
) these checks are made switching off and on the device.
If the condition
does not change, it will be necessary to replace the unit and/or send it back to the supplier to repair.
If a Yellow and the Green LED activates (
0 mA output signal
):
this happens when the “
Cartridge Sensor
” is not
working. First try to perform the procedure of “
ZERO
” as described in the section
“Test and Calibration > Zero
adjust”
then disconnect and connect the unit, finally try to replace a new
“
Cartridge Sensor
”. If the condition is not
change, it will be necessary to replace the unit and/or send it back to the supplier to repair.
If the Green LED, one Yellow and the corresponding Red LED activates (
>24 mA output signal
):
this happens
when the corresponding “
Cartridge Sensor
” is not working or gas concentration is out of scale (
higher than CO>
375 ppm
or Petrol Vap.>23%LEL
). If there are not any gas leaks and the condition is not change, it will be necessary to replace
the unit and/or send it back to the supplier to repair.
INSTALLATION
The detector must be accurately installed according to the national dispositions in force on the safety of the plants
and installation of electric devices.
D
ETECTOR POSITIONING
:
The
Fig. 1
shows the instrument size. The unit must be wall mounted positioned with the
sensor downwards.
It should be fixed at 1.60 m from the floor (
CO gas is lighter as air, while Petrol Vap. are heavier than air
).
E
LECTRICAL
C
ONNECTION
(
see Fig.2
)
: the maximum distance to install each detector from the Central Unit is show in
the
Table 1
. Normally use a four wire shielded cable. The terminals (
+, -, S1, S2
), are plug-in type, it is necessary to
extract them to make the connection. Pay attention when you insert them again, being polarized.
I
MPORTANT
:
Once installation is completed,
it is necessary to adjust the sensors to the environment conditions,
connect the unit, wait about 60÷120 minutes and the carry out the
”
Zero Ad just
”
(see ‘
Test and Calibration >
).
C
OMPATIBILITY WITH OTHER CENTRAL UNITS
: In case of a central unit other then Tecnocontrol,
please verify the
max load resistor as shown in
Fig. 4
.
The max load resistor is 50 ohm with 12Vdc power supply, while is 400 ohm
with 24Vdc power supply.
We suggest using 24Vdc power supply.
WARNING
A
VERAGE LIFETIME
of the sensors in clean air and in normal working condition is
about 3÷4 years for the CO (S1)
and is 5 years for the Petrol vapours (S2)
. After this period the corresponding yellow LED flashes every 4
seconds, it is necessary replacing the CO and/or Petrol Vapours “
Cartridge Sensor
”.
P
ERIODICAL TESTING
: we advise to carry out working tests at least every year. Tests, Zero Adjust and Calibration
with CO/Nitrogen (for S1) and CH
4
/Air (for S2) mixture as explained on
page 6
chapter “
Tests and Calibration
”.
Note:
the detector is not able to detect gas occurring outside the room where it is installed, or under the floor.
S
ENSOR OPERATING LIMITS
:
Both the sensors, in any case, should not be exposed to temperatures lower than -40°
or higher than 60°C. The sensors should not be exposed to an over-range concentration of 1500ppm CO and 60
%LEL Petrol Vapours. If this condition occurs, we suggest replacing the corresponding sensor.
S
AFETY
:
THE
CO
SENSOR
(S1)
IS AN ELECTROCHEMICAL
C
ELL
that contains a small quantity of acid. It is possible that
either a very strong mechanical action or an incorrect instrument use beyond the limits of its operational functioning
could provoke a liquid leak out of the sensor. Should this event occurs, please avoid touching the come out liquid.
Should a contact with either the skin or eyes occur, wash immediately and abundantly with water.
The
electrochemical cell employed detect CO at a very low concentration, has a good resistance towards products such
