During Use; General Instructions For Use; In An Emergency; Switching Off Sentinel Alarms - Dräger PSS BG 4 plus Maintenance Manual

Use
19. Press the left button on the Sentinel briefly to check
the scale illumination. It goes out automatically after a short
time.
When the closed-circuit breathing apparatus is OK, the green
LED flashes and the operating mode display is shown.
The apparatus can now be used.
In the event of an error, the red LEDs flash and an alarm tone
sounds.
WARNING
!
If an error has occurred, the closed-circuit breathing
apparatus must not be used. The closed-circuit
breathing apparatus must be returned to Dräger or
repaired by trained personnel.
Failure to follow this warning could lead to death or
serious injury.
3.4

During use

3.4.1

General instructions for use

The closed-circuit breathing
automatically. Absorption of the CO
be felt, particularly when working under aggravated conditions
with intense breathing. This is perfectly normal and indicates
that the apparatus is functioning correctly.
Always set out in groups with at least two people wearing
the apparatus. Check the oxygen supply approx. every 10 to
15 minutes.
The period of service and retreat should be planned
independently of the low pressure warnings. When the 700 psi/
55 bar residual pressure warning sounds, begin retreat. When
the low pressure warning sounds, cease usage immediately.
When the backlight is required, briefly press the left button

on the Sentinel.
The backlight is switched on for 5 seconds.
When the ambient temperature is to be displayed, press

the right button on the Sentinel briefly.
Instead of the remaining period of use, the temperature is
displayed in °C. The display changes back automatically to
the remaining period of use.
14
30721851.eps
apparatus works fully
generates heat which can
2
CAUTION
!
If the closed-circuit breathing apparatus needs to be
taken off the back in confined spaces, e.g. when
entering an emergency shaft, kinks in the corrugated
hose may cause increased breathing resistance.
Removing the closed-circuit breathing apparatus and
pushing it ahead should therefore be practiced
thoroughly to avoid problems in the form of interrupted
breathing.
3.4.2

In an emergency

Press the yellow panic button.

The main alarm sounds, the function key symbol is displayed
(see chapter 2.6 on page 9) and the red LEDs flash.
In the event of a functional fault in the oxygen supply

press the bypass valve briefly.
Additional oxygen is supplied to the breathing circuit.
WARNING
!
In the event of faults in the closed-circuit breathing
apparatus begin the retreat immediately.
Failure to follow this warning could lead to death or
serious injury.
3.4.3

Switching off Sentinel alarms

Switch off all alarms (except the pre-alarm) as follows:
Press the right and left buttons on the Sentinel

simultaneously until the alarm stops. The Sentinel returns
to normal operating mode and the operating mode display
is shown once again.
If the Sentinel is used as automatic distress signal unit and

the pre-alarm sounds, this pre-alarm can only be
acknowledged by moving the Sentinel.
Page 14
Dräger PSS BG 4 plus
Draeger Training 11/16 rev 1