Bacharach Halogen Monitor, Instruction

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Halogen Monitor Operation
Instruction 3015-4584 Rev 9 7
The operator can reset the peak value to zero by pressing the ENTER
button. The measurement cycle runs for 4 minutes. A log of up to 200
previous measurements can be viewed using the
PPM LOG function (page
10).
PURGE indicates when the monitor is resetting its infrared detector to a
baseline of 0 ppm. The purge cycle runs for 10 seconds.
If the detected gas level exceeds a preset gas-alarm point, the unit will respond by turning ON the front
panel
ALARM (red) light. If the AUDALRM function is activated (page 11), the audible alarm will also turn
ON. Pressing the front panel SILENCE button turns OFF the audible alarm, but the ALARM light will
continue to flash as long as the detected gas level is above the alarm point. The audible alarm will
reactivate if the gas-alarm condition is not cleared within the time period set by the
SILENCE
function (page 11).
If a system fault occurs (see Fault Code list on page 14), the monitor responds by turning ON the front
panel
FAULT (yellow) light. If the AUDALRM function is activated (page 11), the audible alarm will also
turn ON. Pressing the front panel SILENCE button turns OFF the audible alarm, but the FAULT light will
continue to flash as long as the fault is present. The audible alarm will reactivate if the fault condition is
not cleared within the time period set by the
SILENCE function (page 11). Both the FAULT light and
audible alarm will automatically turn OFF after the cause of the fault has been eliminated.
A log of the last 30 fault events can be viewed using the monitor’s FAULTS function (page 10).
2.4 Time Weighted Average (TWA) Operation
2.4.1 Overview
In addition to displaying the current gas level, the monitor can also calculate and display a T ime W eighted
A verage ppm value. This value is available in two formats (8 Hour or Continuous). This provides users
with the most appropriate data on their average ppm exposure in the working environment.
TWA operation is selected by using the 2ndUNIT function.
The two TWA formats are identified by the appearance of either “TWA” or ‘twa” in the upper-right corner
of the
Data Display screen.
•
TWA (upper case letters) is calculated over an 8-hour period. This format is designed to show the
uers’s average ppm exposure level during a typical work day. After 8 hours has expired, an
asterisk (*) will be displayed but the TWA will continue to be updated.
•
twa (lower case letters) is continuously calculated over the operating time of the monitor. This
mode is useful for monitoring an area for a few minutes or more and is the preferred mode of
operation for checking operating room atmospheres.
2.4.2 Starting a New or Continuing TWA/twa
When the monitor is turned ON the following message appears if the monitor is set up to display
TWA/twa.
Press either . . .
•
ENTER to start a new TWA/twa
•
ESC to continue with the current TWA/twa.
PURGE 00020pk
10ppm R134A
PURGE 00TWA
100ppm R134A
PURGE 00twa
100ppm R134A
PRESS ENTER FOR
NEW TWA/twa