Emergency Operations; Preventive Maintenance - S&P UTBS Serie Manuel D'installation

• Turn on the external main power switch to the unit, keeping the control switch in the off
position. After that, check to make sure the input voltage at the unit's electrical terminals
matches the one indicated on the identification plate (the minimum voltage will be 10%
below the rated voltage indicated on the identification plate).
• Do not start up the fan if the duct network is not completely closed, since turning on the
fan with no load can cause over-currents that cause wear to the motor. This can also occur
if the static pressure demanded is greater than the pressure losses that occur in the duct
network. To fix this, close the flow regulator dampers so that there is a greater pressure
loss.
• Turn on the external control switch and stop it a few seconds later.
• Make sure that the motors are rotating in the direction set by the manufacturer (note the
direction of rotation marked on the fan). If the direction of rotation is incorrect, swap the
power phases. To do so, disconnect the unit control switch and the main switch and then
swap the phases.
• Once you've checked the direction of rotation, if you have not noted any strange noises,
you may turn the unit on again.
• Test fan and motor rotation speed using a tachometer.
• Make sure that the unit receives adequate air flow, or else its performance will be seriously
compromised.
• With the unit running, test the current drawn by each electrical component, checking to
make sure that the current does not exceed the limits for each component. Also make sure
there are no phase lags between the currents circulating on each line, except when single-
phase electrical components cause this.
• Test the total current drawn by the unit as a whole, also checking to make sure there are no
phase lags between the currents on the different lines.

8. EMErGENCY OPEraTIONs

• If any problems are noted on the unit, turn it off using the emergency shut-off device.
• These emergency operations will generally be the result of some problem with the electrical
circuit, in which case you may have problems with the motors. You will therefore need to
disconnect the power to locate the fault, which may be inside the unit (short circuit) or ex-
ternal to it (problems with the power supply, voltage variations, etc.).
• In the event of fire, it must be extinguished using suitable extinguishers. Extinguishers
should be appropriate for use on electrical fires.

9. PrEVENTIVE MaINTENaNCE

• Preventive maintenance is a preset programme of checks that is followed regularly to pre-
vent equipment breakdowns.
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