Dräger PSS BG 4 plus

Maintenance
Dräger PSS BG 4 plus 29
4.7 Testing the functional capability of the
Sentinel
The Sentinel can be tested as follows without the cylinder
valve having to be opened:
1. Press the left button on the Sentinel briefly.
The Sentinel switches itself on and tests all interfaces and
the charge status of the battery.
If the Sentinel is OK, a pressure of 0 psi/0 bar and a
remaining period of use of 0 minutes is displayed. The red
LEDs flash.
2. Switch off Sentinel.
Simultaneously press the right and left hand button until a
short beep sounds. The charge status of the battery is
displayed for approx. 3 seconds. The Sentinel switches off.
The Sentinel can display the following results:
4.8 Self-test sequence of the Sentinel
A single alarm tone sounds with each new display. The
following steps are included in the Sentinel self-test sequence:
 Interface testing
The Sentinel tests all inputs and displays all symbols.
 Battery test
When the battery is tested, the Sentinel displays the
battery 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
compressed oxygen cylinder must be >2600 psi/180 bar.
After the test, the "Close cylinder valve" symbol is
displayed and a dual alarm tone sounds.
An alarm sounds at the end of
the self-test. Either the symbol
"a" (function key is removed)
or the symbol "b" (function key
is inserted) is displayed briefly
on the display.
WARNING
After this functional test, the closed-circuit breathing
apparatus must not be used because the cylinder
valve is closed and no oxygen is supplied to the circuit.
Failure to follow this warning could lead to death or
serious injury.
Display on the Sentinel Meaning
The test has been completed
successfully. The closed-
circuit breathing apparatus
cannot be used, however,
as the compressed oxygen
cylinder is closed.
An error has occurred.
Do not use the closed-circuit
breathing apparatus.
Check once again if the
closed-circuit breathing
apparatus functions correctly
or have the device serviced
by Dräger or trained experts.
Battery warning 1
A long warning tone sounds
at the same time.
With normal use of the
Sentinel, the closed-circuit
breathing apparatus remains
fully functional for up to
4 hours. To ensure safe
usage, the battery should be
replaced, however.
!
20421851.eps
35421728.eps
psi
20221851.eps
PSI
Battery warning 2
5 short alarm tones sound
and the red LEDs flash at the
same time.
The Sentinel automatically
powers off and any further
operation is impossible.
The battery must be replaced
before any new operation.
NOTICE
If the pressure in the compressed oxygen cylinder is
less than 2600 psi/180 bar, no high pressure leak test
is performed.
In this case, the Sentinel cylinder pressure and the
remaining period of use are displayed.
Display on the Sentinel Meaning
20321851.eps
PSI
35521728.eps
psi
ab
i
i
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Draeger Training 11/16 rev 1