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11 - SAFETY ELEMENTS
High pressure pressostat
Connected to the compressor discharge, it will stop its operation
when the pressure at that point reaches the setpoint. It
disconnects at 42 bar and it is automatically reactivated.
Low pressure pressostat
When connected to the compressor suction, it will stop its
operation when the pressure at that point goes down below the
tare value (caused by obstructions in the circuit, excessive dirt
in the fi lters, fan stop or ice formation in the evaporator).
This pressostat disconnects at 2 bar and is automatically
reactivated.
Magnetothermals for line protection
They are located at the beginning of the power lines for the
compressors and motor fan(s) to protect them.
Automatic switch in the control circuit
Magnetothermal switch that protects the operation circuit against
continuous surges as well as against high currents of short
duration (short circuits).
Defrost control
This safety device is intended to eliminate ice which could
accumulate in the outdoor coil when the unit is working in the
heating cycle. Defrosting is carried out by the control depending
on the value measured by the sensors on the outdoor coils and
the time set between defrosting operations.
Main door switch
By using a mechanical device, it impedes access to the electric
panel when the unit is with voltage.
Safety at the compressor
Temperature probe for the discharge from the compressor to
protect the unit with discharge temperatures greater than 135ºC.
Condensation and evaporation pressure control
This safety device, integrated in the control, enables managing
the outdoor fans when the units are working in cooling mode with
low outdoor temperatures (condensation control) or in heating
mode with high outdoor temperatures (evaporation control). This
aids the unit’s operation in all the seasons.
In the case of EC electronic fans, such as those that are found in
these units by default, speed control will be proportional based
on the average pressure measured by the pressure transducers
in the outdoor coils.
Smoke detector (optional)
In accordance with standard NF S 61-961, this smoke detection
station uses a LED to indicate the installation status, and if the
probe detects the presence of smoke in the installation, it stops
the operation of the unit.
The station is installed in the factory in the main electric panel
or in the auxiliary electric panel (depending on the model). The
probe is placed on a pillar next to the supply fans.
Anti-fi re safety
The electronic control can activate an anti-fi re safety device that
detains the unit when the return air surpasses a temperature
of 60°C (by default).
It cannot return to operation until the temperature has dropped
to below 40ºC.
Smoke detecting station
Smoke detecting probe
Air inlet tube
Control of air fl ow
- The supply plug-fans (standard) adapt their speed to the
average fl ow measured by the diff erential pressure sensor
and the value set as a setpoint in the electronic control.
- For those units with centrifugal supply fans (optional), a
diff erential pressostat can be incorporated in order to measure
the variation in air fl ow. This pressostat allows the detection of
fan belt breakages, since the fan relay only detects operating
faults that have arisen in the motor. This pressostat is installed
in the factory in the main electric panel or in the auxiliary
electric panel (depending on the model). This safety device
is mandatory for units with electrical heaters and with gas
burners if the unit does not have the supply plug-fans.
Summary of Contents for 50EH 1100
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