Description; Operational Description - Tecno Control SE237S F1-H Manuel D'utilisation

IST-2137.SF01.01
EN

DESCRIPTION

The SE237SF series is a gas detector for refrigerant gases (halocarbons) with a semiconductor sensor calibrated
for different gases for application in alarm systems for industries of refrigerants, laboratories, cylinders warehouses
storage, compressors rooms, and environments in general where it is necessary to monitor any leaks of refrigerant
gases. The code of each model identifies the type of gas detected and its full scale.
The detector comprise of a thermoplastic case in which the electronic circuit and the terminals are mounted. The
enclosure has downward facing cylindrical sensor housing with inside a replaceable "Cartridge Sensor" that con-
tains the sensitive element with the identification and calibration data, for the specific detected gas.
The SE237SF has three alarm levels, with different set-up as listed in
free single pole contacts (SPST). On the front panel there are two F1 e F2 key, using for the Test and Calibration
routine, protected by a code, and 5 LEDs shows the working conditions.
rd
3 Red LED "ALARM 3":
nd
2 Red LED "ALARM 2":
st
1 Red LED "ALARM 1":
Green LED "ON":
Yellow LED "FAULT":
Additionally, the detector has a 4÷20mA linear output signal (S) with 1000 ppm F.S. of the detected gas. This out-
put is connectable to a remote control panel.

OPERATIONAL DESCRIPTION

The semiconductor sensor has excellent sensitivity to the gas to be detected, also to very low concentrations.
Its use avoids potential problems or economic damage caused by a gas leak refrigerant.
The semiconductor sensor has a good resistance to poisoning but it can be influenced from changes of the envi-
ronmental parameters (temperature and humidity) and has a relatively low selectivity (sensitivity to other refriger-
ants gases or interfering gases, as solvents, exhaust gas of engines, hydrocarbons and hydrogen).
If the influence to the environmental parameters can be compensated, by performing the automatic zero of the de-
tector, the interference of other gas temporarily present in the environment (e.g. Exhaust gases of motor vehicles)
can be improved by setting delays in the activation of the alarms. The low selectivity to halocarbons can be used in
the monitoring of environments or plants where are possible leaks of different refrigerants.
Preheating: when powered, the sensor needs a time of preliminary heating of about 120 seconds. During this peri-
od the yellow LED "FAULT" flashes. After this period, the yellow LED light off, the green LED "ON" illuminates to in-
dicate normal functioning. After this period the unit is able to detect gas even if it attains the optimum stability con-
ditions after about 48 hours continual functioning.
Normal operation: the green LED "ON" should be light on.
st
The 1 Red LED (ALARM 1) illuminates when the Gas concentration attains 1
seconds , the "ALARM 1" relay will activate.
nd
The 2 Red LED (ALARM 2) illuminates when the Gas concentration attains 2
seconds, the "ALARM 2" relay will activate.
rd
The 3 Red LED (ALARM 3) illuminates when the Gas concentration attains 3
seconds, 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. The "FAULT" 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 period of life (about 5 years) and its correct operation is no longer guaranteed. The detector keeps on
operating normally but it is necessary to replace, as soon as possible, the "Cartridge Sensor" with a new one. The
type to be required is listed in 2
Yellow LED activates, 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
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
made connecting 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 (0mA output signal): this happens when the "Cartridge Sensor" is not working.
First try to 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.
All LED activate (>24mA output signal): this happens when the "Cartridge Sensor" is not working or gas concentra-
tion is out of scale (higher than 1000 ppm) or a concentration of interfering gas is very high. Ventilate the ambient
well, making sure to let out the refrigerant gas or the interfering ones. If there is no gas leak and the condition per-
sists after you have ventilated the room, it may be that the sensor has reached its end of life, then replace the "Car-
tridge Sensor". If the condition does not change, it will be necessary to replace the unit and/or send it back to the
supplier to repair.
TECNOCONTROL S.r.l. Via Miglioli 47 SEGRATE ( MI )
Istruzione / User's Manual / Manuel d'utilisation
rd
3 relay activation
nd
2 relay activation
st
1 relay activation
normal working condition
the sensor should be faulty, disconnected, out of scale or expired.
nd
column Table 4. The replacement procedure is described in the attached manual.
Table 2. The sealed relays are with tension
st
nd
rd
(see Table 3). 2) The "Cartridge Sensor" is not working,
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alarm level and after about 12
alarm level and after about 30
alarm level and after about 60
(see Table 4) these checks are