IST-2138.EO01.01
Istruzione / User’s Manual / Manuel d’utilisation
Pag.5/11
TECNOCONTROL S.r.l. Via Miglioli 47 SEGRATE ( MI )
Tel: 02/26 92 28 90 Fax: 02/21 33 734
decreasing may be caused by combustion, leakage of other gases (toxic and / or flammable) or also displaced by
inert gases increasing in the environment (nitrogen, helium, argon etc.). A high concentration, more than 24%v/v O
2
is irritating to the respiratory tract and can cause effects on the central nervous system, eyes and lungs that can be
damaged by the inhalation of high concentrations.
OPERATIONAL DESCRIPTION.
The electrochemical sensor is temperature compensated, but is sensitive to extreme humidity variations.
Note
that the Led are not visible when the enclosure is closed.
Preheating
: when powered, the sensor needs a time of preliminary heating of about 60 seconds. During this period
the yellow Led “
FAULT
” flashes. After this period, the yellow Led light off, the green Led “
ON
” illuminates to indicate
normal functioning. After this period the unit is able to detect gas even if it attains the optimum stability conditions
after about 15 minutes continual functioning.
Normal operation
: the green Led “
ON
” should be light on.
ALARMS:
different alarms levels can be set by Dip-Switch (
see table 2
).
The 1
st
red Led
(
ALARM 1
) illuminates when Oxygen concentration attains 1
st
alarm level. And after about 3 sec-
onds the “
ALARM 1
" relay will activate.
The 2
nd
red Led
(
ALARM 2
) illuminates when Oxygen concentration attains 2
nd
alarm level and after about 3 sec-
onds, the “
ALARM 2
" relay will activate.
The 3
rd
Red LED
(
ALARM 3
) illuminates when Oxygen concentration attains 3
rd
alarm level and after about 3 sec-
onds, the “
ALARM 3
" relay will activate.
Faults
:
the instrument signal different kind of failures, as listed below. The yellow Led illuminates, the "
S
" output
falls down to 0mA and the “
FAULT
”
normally activated relay deactivate. This relay, if necessary, can be used both to
signal remotely an occurred damage and to signal the absence of power to the instrument.
Yellow Led illuminates each 4 seconds (
with green Led activate
):
this happens when the “
Cartridge Sensor
” has
overcome its theoretical period of life (
2 years approximately
) 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 “
Cartridge
” with a new
one. The type to be required is described on
Page1
. The replacement procedure is described in the attached manual.
Yellow Led activate, green Led off (
FAULT relays activate and 0mA output signal
):
this signal different kind of faults.
1)
The Dip Switch set up is wrong, please verify (
see Table 2
).
2)
The “
Cartridge Sensor
” is not working, please replace
with new one.
3)
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 on page 1
) these checks are made connect-
ing and disconnecting 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.
Yellow and green Led activates (
FAULT relays activate and 0mA output signal
):
this happens when the “
Cartridge
Sensor
” is not working. First try to perform the procedure of “
Calibration in Air
” as described in the section
“
Test and
Calibration > Calibration in Air
”
, 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.
All Led activates (
FAULT relays activate and >24mA output signal
):
this happens when the “
Cartridge Sensor
” is not
working or gas concentration is out of scale (higher than 25%v/v O
2
). If there are not any gas leaks and the condi-
tion 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 and testing according to the national dispositions in force on the safety of
the plants and installation of electric devices in areas with danger of explosion.
Mounting
: The
Fig. 2
shows the instrument size. The unit must be positioned vertically with the sensor downwards.
Detector positioning
:
It should be fixed at 1.60 m from the floor (the O
2
gas is lighter as air).
Electrical Connection (
see Fig.2
)
: the maximum distance to install each detector from the power supply show in the
Table 1
.
If more than one detector is to be powered in parallel, it is necessary to consider the voltage drop across the
supply cable. Normally use a two wire cable (
not shielded
) for power the conductors for output relay.
If the
output signal is used in mA, please use 3 conductors screened conductors for relay output. The max load
resistor is 50 ohm with 12Vdc power supply, while is 400 ohm with 24Vdc power supply (
see fig.4
).
Power Supply terminals, on the main board, are plug-in type, it is necessary to extract them to make the connection.
Pay attention when you insert them again, being polarized. The relays terminals, on outputs board, are fixed.
The
solid state relays are
tension free
SPST (
S
ingle
P
ole
S
ingle
T
hrow)
contacts and should be set NO (Normally Open) or NC
(Normally Closed) by positioning the 4th Dip-Switch (
see Table 3
). With the
Dip-Switches from 1 to 3 the concentra-
tion for alarm activations is determined.
Note: Dip-Switch should be set with instrument powered off. Dip-Switch settled in reserved positions acti-
vates FAULT Led indication (see “Operational Description > Faults”).
Important:
Once installation is completed,
power up the unit, wait about 20 to 30 minutes and then to adjust the
sensor to the environment, only if it is necessary,
carry out the
”
Zero Adjust
”
(see ‘
Test and Calibration
).
WARNING
Average life
: The sensitive element used in this detector has an excellent stability in time. In fresh air and in normal
working condition the
sensor's life is
about 2 years
. After this period the yellow Led “
FAULT
” flashes every 4 sec-
onds, is necessary replacing the “
Cartridge Sensor
”.
Periodical testing
: we advise to carry out working tests every 6 or 12 months, as explained on chapter “
Tests and
Calibration
”.
