Biosystems MultiPro Reference Manual - page 8
7
Recommended calibration frequency is
discussed in Appendix B.
1.4 Alarm
logic
MultiPro gas alarms can be adjusted with
Biosystems BioTrak Software through a PC
with an IrDA port or directly with the MODE
button (see Chapter 6 for direct programming
instructions). Alarms may be set anywhere
within the nominal range of the specific
sensor type. When an alarm set point is
exceeded a loud audible alarm sounds, and
the bright red LED alarm lights flash.
1.4.1 Atmospheric hazard alarms
MultiPro portable gas
detectors have been designed for the
detection of deficiencies of oxygen,
accumulations of flammable gases and
vapors, and accumulations of specific
toxic gases. An alarm condition
indicating the presence of one or more
of these potentially life-threatening
hazards should be taken very seriously.
In the event of an alarm
condition it is important to follow
established procedures. The safest
course of action is to immediately leave
the affected area, and to return only after
further testing determines that the area is
once again safe for entry. Failure to
immediately leave the area may result in
serious injury or death.
A rapid up-scale
reading followed by a declining or
erratic reading may indicate a
hazardous combustible gas
concentration that exceeds the
MultiPro’s zero to 100 percent LEL
detection range.
The combustible gas alarm is activated when
the percent LEL (Lower Explosive Limit) gas
concentration exceeds any pre-set alarm
level.
Two oxygen alarm set points have been
provided; a danger alarm for low
concentrations associated with oxygen
deficiency and a warning alarm for high
concentrations associated with oxygen
enrichment.
Four alarm set points have been provided for
each toxic gas sensor: Warning, Danger,
STEL (Short Term Exposure Limit) and TWA
(Time Weighted Average).
S
E
N
S
O
R
W
A
R
N
I
N
G
D
A
N
G
E
R
S
T
E
L
T
W
A
CO 35 100 100 35
H
2
S 10 20 15 10
MultiPro Default Toxic Sensor Alarm Levels
Appendix A discusses alarm levels and
factory default alarm settings.
1.4.2 Low battery alarms
The MultiPro may be equipped with either
rechargeable Lithium Ion (Li-Ion) or alkaline
battery packs. The MultiPro includes multi-
staged alarms for either battery type to let the
user know that the battery is running low.
For detailed information concerning the
low battery alarms, see section 2.4.5.
Use only Duracell
MN1500 or Ultra MX1500, Eveready
Energizer E91-LR6, Eveready EN91
batteries. Substitution of batteries may
impair intrinsic safety.
1.4.3 Sensor over range alarms.
The MultiPro will go into alarm if a sensor is
exposed to a concentration of gas that
exceeds its established range. In the case of
an LEL reading that exceeds 100% LEL, the
LEL channel will be automatically disabled by
the instrument and the instrument will remain
in constant alarm until it is turned off, brought
to an area that is known to be safe, and then
turned back on. The display will show “OL”
in place of the sensor reading for any
channel that has gone into over range alarm.
See section 2.4.5 for further details on
sensor over range alarms.
A sensor range chart is provided in
Appendix C.
In the event of an LEL
overrange alarm the MultiPro must be
turned off, brought to an area that is
known to be safe and then turned on
again to reset the alarm.
1.4.4 LEL response failure due to lack of
O
2
alarm
The MultiPro features automatic warning
against LEL sensor response failure due to
lack of oxygen. See section 2.4.7 for details.
1.4.5 Security
beep/flash
The MultiPro includes a security beep
function that is designed to notify the user