biosystems PhD Lite User Manual

44
Explosive Limit) or in terms of the percent by volume of
methane (CH
4
).
With the PhD Lite configured to read in terms of percent
by volume of methane (CH
4
), the LEL sensor must be
calibrated to the actual percent by volume of methane
used in Biosystems calibration gas cylinders, not to the
%LEL value given on the label. The actual percentage
by volume of CH
4
will be stamped in indelible black ink
on the side of the cylinder body. For example,
Biosystems popular all-in-one mix, part number 54-
9044E, with 50% LEL propane equivalent will list
±1.62% CH
4
on the side of the cylinder body. In this
case, the percent by volume CH
4
calibration gas value
should be set to 1.62%.
For easy reference, the actual percent by volume of CH
4
for the following Biosystems LEL component mixtures is
listed in the following table.
LEL Component
Description
Volume %
Methane (CH
4
)
50% LEL Methane
±2.50
50% LEL Propane
Equivalent
±1.62
50% LEL Pentane
Equivalent
±1.25
Table 4.7.2.1 Percent LEL versus percent by volume of
methane for common Biosystems calibration gas
cylinders.
To change the calibration gas value setting from
percentage of LEL to percent by volume of methane or
vice versa:
1. Enter the Calibration Menu as described above in
section 4.7.1.
FRESH_AIR SPAN_CAL
GAS_VALUES
REMIND
IQ LINK EXIT
CAL LOCK
2. Use the navigation arrows to highlight GAS
VALUES and press the MODE button.
Depending on the existing calibration gas value setting,
the instrument will display the calibration value either as
percentage of LEL or as percent by volume of methane
(CH
4
).
CALIBRATION GAS
LEL 50.0%
EXIT
or
CALIBRATION GAS
CH
4
2.50%
EXIT
3. Press the left navigation arrow once to highlight LEL
or CH
4
.
CALIBRATION GAS
LEL 50.0%
EXIT
or
CALIBRATION GAS
CH
4
2.50%
EXIT
4. The up and down navigation arrows may be used to
toggle between the calibration gas settings (LEL or
CH
4
). Once the appropriate setting is shown, press
the right navigation arrow once to highlight the
calibration gas concentration in percent of LEL or
percent by volume (CH
4
). To change the calibration
gas concentration setting, use the up and down
navigation arrows to increase or decrease the
amount.
CALIBRATION GAS
CH
4
2.50%
EXIT
↓
CALIBRATION GAS
CH
4
2.49%
EXIT
5. Once the appropriate calibration gas type and
concentration are reached, press the MODE button
to confirm the setting.
Save Changes?
YES NO CANCEL
6. Press the MODE button with YES highlighted to
save the new settings.
Cal Gas Values
Saved
4.7.2.2 Changing the direct reading setting of the
CO Plus sensor from CO to H
2
S
Biosystems CO Plus sensor is designed for the
simultaneous detection of both carbon monoxide and
hydrogen sulfide, but it can only be calibrated for the
direct detection of one of these hazards.
For instruments with the CO Plus sensor, calibration gas
settings determine whether the PhD Lite is configured
for the direct detection of CO or H
2
S. When the
calibration gas selected is CO, the PhD Lite will show
CO+ on the current gas readings screen. Alternately,
when the calibration gas selected is H
2
S, the PhD Lite
will show H
2
S+ on the current gas readings screen.
O
2
LEL CO+
20.9 0 0
Current gas readings screens with CO Plus sensor;
calibration gas value set to CO.
O
2
LEL H
2
S+
20.9 0 0
Current gas readings screens with CO Plus sensor;
calibration gas value set to H
2
S.
To change the direct reading selection of the CO Plus
sensor through the calibration gas value settings:
1. Enter the Calibration Menu as detailed above in
section 4.7.1.

biosystems PhD Lite Specifications

General

Brand	biosystems
Model	PhD Lite
Category	Security Sensors
Language	English