3
English
USE INSTRUCTIONS AND LIMITATIONS
Important
Before use, each person using this equipment must read and understand these User Instructions.
Keep these instructions for reference.
Use For
Monitoring for carbon monoxide level in compressed air intended for respiratory protection systems.
Do Not Use For
Monitoring other compressed gas streams.
General Description
These User Instructions apply to the 3MTMCO Monitor mounted inside some of the 3MTMPortable
Compressed Air Filter and Regulator Panels and the 3M
TM
Retrofit CO Monitor Kit W-2808/37027.
The retrofit kit includes the 3M CO monitor and accessories to attach the CO monitor to a
3
/
8
-inch
port on a filter and regulator panel that does not currently have CO monitoring capability, such as
the 3M
TM
Compressed Air Filter and Regulator Panel W-2806/07006.
The 3M carbon monoxide monitor is designed to provide continuous, direct read CO monitoring
for compressed air used with supplied air respirators. An internal microprocessor controls the
indication and alarm functions in response to the signals of an electrochemical CO sensor. It
continuously monitors a compressed air sample introduced to its sensor at an approximate rate
of 1.0 standard cubic foot per hour (scfh) and gives an alarm when the CO in the sample reaches
a preset level (10 ppm in USA; 5 ppm in Canada).
The CO monitor is a battery powered unit utilizing two 9 volt alkaline batteries. It is designed to
be intrinsically safe when used on battery power. The CO monitor is CSA certified intrinsically
safe for Class I, Div. I, Groups A,B,C, and D Hazardous Locations when utilizing two 9 volt
alkaline batteries to power the monitor.
The components of the monitor are assembled into a black powder-coated aluminum housing
6˝ H x 4˝ W x 2˝ D overall. A hose barb, with plastic sample tube attached for introducing the
sample gas, extends from the bottom. Available at the front face are the OFF/ON/TEST switch,
the display (LCD), SPAN and ZERO adjustments.
The left side contains the indicating lights, the alarm buzzer, and the remote alarm jack.
Accessible on the right side are the two battery drawers and the auxiliary power jack. (Fig. 1)
Buzzer - Provides continuous tone
during high “CO” alarm; a pulsing tone
during certain malfunction conditions.
Display - LCD type refreshed
every 0.8 seconds; the red LED
light faintly blinks at same time.
Span & zero potentiometers
used in calibrating.
Screw sealed
access hole to
alarm level
potentiometer.
“Transistor”
type battery
holders
Auxiliary “power
source” jack
Air sample tube
Remove knurl thumbscrews for
access to “CO” sensor. Bottom pla te
sensor/sample tube assembly. Can be
moved approx. 2-3˝ before sensor wire
connections limit travel.
On/Off/Test switch-three
position type. Alternate
on-off position with
momentary “test”
position.
Remote alarm jack; for
plugging remote alarm
devices or relays to be
energized when monitor
goes into alarm.
Green normal LED
light; comes on steady
when monitor on &
goes off in alarm
conditions.
Yellow low battery
LED light; comes on
when 9 volt battery
voltage falls below
about 7.0 volts.
Red alarm, LED light;
blinks faintly during
normal operations
& on steady during
high “CO” alarm
conditions.
Fig. 1