Dräger PSS BG 4 RP, Instructions For Use Manual

Page: 69 / 78

Maintenance
69
en
4.8 Self-test sequence of the Bodyguard
A single alarm tone sounds with each new display. The
following steps are included in the Bodyguard self-test
sequence:

Interface testing
The Bodyguard tests all inputs and displays all symbols.

Battery test
When the battery is tested, the Bodyguard displays the bat-
tery symbol. On the display, the bar chart runs from left to
right and the software version number is displayed.

High pressure leak test
For the high pressure leak test, the pressure in the com-
pressed oxygen cylinder must be >165 bar.
After the test, the "Close cylinder valve" symbol is dis-
played and a dual alarm tone sounds.
An alarm sounds at the end of
the self-test. Either the symbol
"a" (the function key is
removed) or the symbol "b"
(the function key is inserted) is
displayed briefly on the
display.
4.9 Replacing the pressure reducer
4.9.1 Removing the pressure reducer
1. Remove the compressed oxygen cylinder
(see chapter 4.2.1 on page 57).
2. Remove switch box.
3. Disconnect the high pressure sensor connector cable from
the switch box.
4. Unfasten the medium-pressure hose from the pressure
reducer (see chapter 4.2.11 on page 60).
5. First unfasten the grub screw, then the crown nut.
6. Remove the bypass valve switch and spring.
7. Take the pressure reducer out of the closed-circuit breathing
apparatus.
8. Unfasten the high pressure sensor using an open end wrench
(SW 17) and remove from the pressure reducer.
9. Insert the bypass valve switch and spring into the pressure
reducer and screw the crown nut onto the pressure reduc-
er.
4.9.2 Installing the pressure reducer
1. Unfasten the crown nut from the pressure reducer.
2. Remove the bypass valve switch and spring.
3. Insert a new sealing ring and the high pressure sensor into the
pressure reducer and tighten with an open end wrench (SW
17; torque: 15+5 Nm).
4. Install the pressure reducer into the closed-circuit breathing
apparatus.
5. Pay attention to the correct seating of the rubber disc and the
sealing ring and insert the spring and the bypass valve switch.
6. Install the reinforcing plate and the crown nut.
7. Secure the crown nut using the grub screw.
8. Connect the high pressure sensor connecting cable to the
switch box.
9. Insert the medium-pressure hoses into the pressure reducer.
They must engage into place. Pull gently on the plugs to
check that the medium-pressure hoses fit correctly.
NOTICE
If the pressure in the compressed oxygen cylinder is
less than 165 bar, no high pressure leak test is
performed.
In this case, the Bodyguard cylinder pressure and the
remaining period of use are displayed.
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a b
i i
WARNING
When installing the pressure reducer, ensure that no
dust or finger grease reaches the pressure reducer.
Contact with oil, grease or similar contaminants
can result in serious injuries or death. Either a fire,
an explosion or both may also be caused.
Wear suitable protective gloves!
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!