• Connect the hose to the fan unit and turn it
clockwise about 1/8 of a turn. Fig. 7.
• Check that the hose is firmly secured.
d) Particle filters/combined filters
Two filters or combined filters of the same type and
class must always be used at the same time. Proceed
as follows:
1. Particle filter SR 510
• Check that the gaskets in the filter mounting of the
fan unit are in place and are in good condition. Fig.
9.
• Snap the particle filter onto the filter adapter. Do not
press onto the centre of the filter - it might damage
the filter paper. Fig. 10.
• Screw the adapter into the filter mounting so far
that the adapter will be in contact with the gasket.
Then turn it about 1/8 turn further in order to
ensure a good seal. Fig. 11.
• Fit one pre-filter into the filter holder. Fig. 12.
• Press the filter holder onto the particle filter. Fig. 13.
2. Particle filter SR 710
• Check that the gaskets in the filter mounting of the
fan unit are in place and are in good condition. Fig.
9.
• Screw the filter into the filter mounting so far that
the adapter will be in contact with the gasket. Then
turn it about 1/8 of a turn further in order to ensure
a good seal. Fig. 11.
• Fit one pre-filter into the filter holder. Fig. 12.
• Press the filter holder onto the particle filter. Fig. 13.
3. Combined filters
• Check that the gaskets in the filter mounting of the
fan unit are in place and are in good condition. Fig.
9.
• Snap the particle filter onto the gas filter. The
arrows on the particle filter must point towards the
gas filter. Do not press onto the centre of the filter
- it might damage the filter paper. Fig. 14.
• Screw the combined filter into the filter mounting
until it is in contact with the gasket. Then turn it
about 1/8 turn further to ensure a good seal. Fig.
15.
• Fit a pre-filter into filter holder. Fig. 12.
• Press the pre-filter holder onto the combined filter.
Fig. 16.
Filter SR 599 is a combined gas filter and particle filter
and is screwed directly into the filter mounting of the
fan. Proceed as described above.
2.6 Operation/performance
• Start the fan by pressing the control button. Fig. 17.
• After the button has been pressed, a programmed
test will be run on the fan unit, during which the
symbols on the display will light up, the sound
signal will sound and the vibrator will vibrate twice.
Fig. 18.
• After the internal test, all symbols will be extin-
guished except the small green fan symbol. This
indicates normal operating status with a flow of at
least 175 l/min.
• If the button is pressed again, boosted operating
status will be activated, with a flow at least 225 l/
min. This is indicated by the larger green fan
symbol lighting up.
38
• To revert to normal operation, press the control
button once again.
• To switch off the fan unit, keep the control button
depressed for about two seconds.
2.7 Performance check
Check of the minimum flow - MMDF
MMDF stands for Manufacturer's Minimum Design
Flow rate. See 3. Technical specification. This flow
should be checked on every occasion before the fan
unit is used. Proceed as follows:
• Check that the fan unit is complete, correctly
mounted, thoroughly cleaned and undamaged.
• Start the fan unit. See 2.6.
• SR 550 PU breathing hose:
Place the head-top in the flow meter and grip the
lower part of the bag to seal around the breathing
hose. Grip the flow meter tube with the other hand
so that the tube points vertically upwards from the
bag. Fig. 19.
• SR 551 Rubber breathing hose:
Place the head-top in the flow meter and grip the
lower part of the bag to seal around the upper
attachment of the breathing hose. (Attachment is
shown in fig. 8). Note. You must not grip around
the rubber hose itself as this would either
obstruct the air flow or cause failure to achieve
a proper seal. Grip the flow meter tube with the
other hand so that the tube points vertically
upwards from the bag. Fig. 19.
• Read the position of the ball in the tube. This
should hover at a level with or slightly above the
upper marking on the tube, (175 l/min). Fig. 20.
If minimum flow is not achieved, check that
- the flow meter is held upright,
- the ball moves freely,
- the bag seals well around the hose.
Checking the alarms
The equipment is designed to provide a warning if the
air flow is obstructed. This alarm function should be
checked in conjunction with the flow check before the
equipment is used. Proceed as follows:
• Provoke an air flow stoppage by gripping the top
part of the bag or by shutting off the flow meter
outlet. Fig. 21.
• The fan unit should then initiate alarms by sound
and light signals and vibrations.
• If the air is again allowed to flow, the alarm signals
will automatically cease after 10-15 seconds.
• Switch off the fan unit and remove the flow meter.
2.8 Putting the equipment on
After the filters have been fitted, a performance check
has been carried out and the head top has been
connected, the equipment can be put on. Before
putting it on, read the user instructions for the head
top.
• Take the fan unit on and adjust the belt so that the
fan unit is firmly and comfortably secured at the
back of your waist. Fig. 22.
• Start the fan by pressing the control button. See
also 2.6 above.
• Put the head top on.
• Make sure that the breathing hose runs along your
back and is not twisted. Fig. 22. Note that when a
full face mask is used, the hose should run along
your waist and up along the chest. Fig. 23.