Macurco CM-6 User manual

IMPORTANT: Keep these user instructions for reference.
Macurco™ CM-6, CM-12
Carbon Monoxide Detector, Controller and Transducer
User Instructions

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 2 |Page
Table of Contents
1General Safety Information........................................................................................................................................................4
1.1 General Description...........................................................................................................................................................4
1.2 List of warnings and Cautions............................................................................................................................................4
2Use Instructions and Limitations................................................................................................................................................5
2.1 Use For ..............................................................................................................................................................................5
2.2 Do NOT use for ..................................................................................................................................................................5
2.3 Features.............................................................................................................................................................................6
2.4 Specifications ....................................................................................................................................................................6
2.4.1 6-Series Low Voltage.....................................................................................................................................................6
2.4.2 12-Series Line Voltage...................................................................................................................................................6
3Installation Instructions .............................................................................................................................................................7
3.1 Location............................................................................................................................................................................. 7
3.2 Installation......................................................................................................................................................................... 7
3.2.1 6-Series Low Voltage..................................................................................................................................................... 7
3.2.2 12-Series Line Voltage.................................................................................................................................................12
3.3 Terminal Connection .......................................................................................................................................................17
3.3.1 6-Series Low Voltage................................................................................................................................................... 17
3.3.2 12-Series Line Voltage.................................................................................................................................................17
4Operations ...............................................................................................................................................................................18
4.1 Power up .........................................................................................................................................................................18
4.2 Display turned “On” ........................................................................................................................................................18
4.3 Display turned “Off”........................................................................................................................................................19
4.4 4-20 mA Loop .................................................................................................................................................................. 19
4.5 Default – Factory Settings ...............................................................................................................................................20
4.5.1 Selecting Default Configuration – “dEF” .....................................................................................................................20
4.5.2 Power-Up Test Setting – “PUt” ................................................................................................................................... 21
4.5.3 Display Setting – “dSP” ...............................................................................................................................................21
4.5.4 Buzzer Setting – “bUZ”................................................................................................................................................21
4.5.5 Alarm Relay Setting – “ArS” ........................................................................................................................................ 21
4.5.6 Alarm Relay Configuration – “Arc”..............................................................................................................................21
4.5.7 Fan Relay Setting – “FrS”.............................................................................................................................................21
4.5.8 Fan Relay Delay Setting – “Frd” .................................................................................................................................. 21
4.5.9 Fan Relay Minimum Runtime Setting – “Frr”.............................................................................................................. 22
4.5.10 Fan Relay Latching Setting – “FrL”.......................................................................................................................... 22
4.5.11 Trouble Fan Setting – “tFS” ....................................................................................................................................22
4.5.12 4-20mA Output setting – “420”..............................................................................................................................22
4.5.13 Calibration Period Settings – “CAL” ........................................................................................................................22
5Troubleshooting.......................................................................................................................................................................23
5.1 On-Board Diagnostics......................................................................................................................................................23
5.1.1 4-20mA troubleshooting.............................................................................................................................................23
5.1.2 “t” error codes ............................................................................................................................................................23
5.2 Sensor Poisons ................................................................................................................................................................24
5.3 End-of-Life Signal.............................................................................................................................................................24
6Maintenance ............................................................................................................................................................................24
6.1Sensor Life Reset .............................................................................................................................................................24
6.2 Cleaning........................................................................................................................................................................... 25
7Testing......................................................................................................................................................................................25

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 3 |Page
7.1 Testing .............................................................................................................................................................................26
7.1.1 Operation Test ............................................................................................................................................................26
7.1.2 Manual Operation Test ...............................................................................................................................................26
7.2 Calibration and Test Kits.................................................................................................................................................. 27
7.3 Gas Testing ...................................................................................................................................................................... 28
7.3.1 Testing the Fan Relay ..................................................................................................................................................28
7.3.2 Testing the Alarm Relay .............................................................................................................................................. 28
7.3.3 Testing the 4-20mA loop............................................................................................................................................. 29
7.3.4 Aerosol Carbon Monoxide Test .................................................................................................................................. 29
7.4 Field Calibration Procedure.............................................................................................................................................29
8Appendix A – Table of Images..................................................................................................................................................31
9Appendix B – Menu Structure..................................................................................................................................................32
9.1 Main Menu......................................................................................................................................................................32
9.2 Auto Test Menu “bUZ” ....................................................................................................................................................33
9.3 Select Test Menu “tst” ....................................................................................................................................................40
9.4 Calibration Menu “CAL” ..................................................................................................................................................41
9.5 Sensor Reset Menu “SEn” ...............................................................................................................................................42
11 Macurco Gas Detection Product limited warranty .................................................................................................................. 43
Technical Support Contact Information ............................................................................................ Error! Bookmark not defined.
General Contact Information............................................................................................................. Error! Bookmark not defined.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 4 |Page
1General Safety Information
The following instructions are intended to serve as a guideline for the use of the Macurco CM-6 and CM-12 Carbon Monoxide
Detector. This manual will refer to these devices as CM-xx unless content is specific to a model. This manual is not to be
considered all-inclusive, nor is it intended to replace the policy and procedures for your facility. If you have any doubts about
the applicability of the equipment to your situation, consult an industrial hygienist or call Technical Support at 1-844-325-3050.
1.1 General Description
The Macurco CM-xx is a dual relay Carbon Monoxide (CO) detector, controller, and transducer. Available in both a low voltage
(CM-6) and line voltage (CM-12) option. The CM-xx has selectable 4-20 mA output, buzzer and digital display options. It is an
electronic detection system used to measure the concentration of Carbon Monoxide and provide feedback and automatic
exhaust fan control to help reduce CO concentrations in parking garages, maintenance facilities or other commercial
applications. The CM-xx is a low-level meter capable of displaying in the range 0-200 ppm (parts per million) of Carbon
monoxide. The CM-xx is factory calibrated and 100% tested for proper operation but can also be calibrated in the field.
1.2 List of warnings and Cautions
WARNING
Each person using this equipment must read and understand the information in this user manual
before use. Use of this equipment by untrained or unqualified persons or use that is not in
accordance with this user manual, may adversely affect product performance.
Use only for monitoring the gas which the sensor and monitor is designed to detect. Failure to
do so may result in exposures to gases not detectable and cause serious injury or death. For
proper use, see supervisor or user manual, or contact Technical Support at 1-844-325-3050.
This equipment may not function effectively below 0°F or above 125°F (-18°C or above 52°C).
Using the detector outside of this temperature range may adversely affect product performance.
This detector helps monitor for the presence and concentration level of a certain specified
airborne gas. Misuse may produce an inaccurate reading, which means that higher levels of the
gas being monitored may be present and could result in overexposure and cause serious injury
or death. For proper use, see supervisor or User manual, or contact Technical Support at 1-844-
325-3050.
High voltage terminals (120/240 VAC) are located within this detector, presenting a hazard to
service technicians. Only qualified technicians should open the detector case and service the
internal circuits. Ensure power is de-energized from the detector relays prior to servicing the
unit. Failure to do so may result in electrical shock.
Do not disassemble unit or attempt to repair or modify any component of this instrument. This
instrument contains no user serviceable parts, and substitution of components may impair
product performance.
Using a certified gas with a concentration other than the one listed for this detector when
conducting a calibration or calibration verification test (bump test) will produce inaccurate
readings. This means that higher levels of the gas being monitored may be present and could
result in overexposure. For proper use, see supervisor or User manual, or contact Technical
Support at 1-844-325-3050.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 5 |Page
The following steps must be performed when conducting a calibration or calibration verification
test (bump test) to ensure proper performance of the monitor. Failure to do so may adversely
affect product performance.
•When performing a calibration or calibration verification test (bump test), only use
certified calibration gas at the required concentration level.
•Do not test with expired calibration gas.
•Do not cover or obstruct display or visual alarm cover.
•Ensure sensor inlets are unobstructed and are free of debris
Failure to follow instructions outlined in this user manual can result in sickness or death.
2Use Instructions and Limitations
WARNING
Each person using this equipment must read and understand the information in this user manual
before use. Use of this equipment by untrained or unqualified persons or use that is not in
accordance with this user manual, may adversely affect product performance.
2.1 Use For
The CM-xx provides CO detection and automatic exhaust fan control for automotive maintenance facilities, enclosed parking
garages, utility rooms, warehouses and other commercial applications. The CM-xx meets the requirements of the Uniform
Building Code for enclosed garages and meets OSHA standards for CO exposure. CM-xx can be used stand alone, with the
Macurco DVP-120 Detection and Ventilation Control Panel, other 12 VAC or 24 VDC fire/security panels or building automation
systems.
WARNING
Use only for monitoring the gas which the sensor and monitor is designed to detect. Failure to do
so may result in exposures to gases not detectable and cause serious injury or death. For proper
use, see supervisor or user manual, or contact Technical Support at 1-844-325-3050.
2.2 Do NOT use for
The CM-xx is not intended for use in hazardous locations or industrial applications such as refineries, chemical plants, etc. Do
not mount the CM-xx where the normal ambient temperature is below 0°F or exceeds 125°F (-18°C or above 52°C). The CM-xx
mounts on a type 4S electrical box supplied by the contractor. Do not install the CM-xx inside another box unless it has good air
flow through it.
WARNING
This equipment may not function effectively below 0°F or above 125°F (-18°C or above 52°C).
Using the detector outside of this temperature range may adversely affect product performance.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 6 |Page
2.3 Features
•ETL LISTED Certified to CSA C22.2 No 61010-1, Conforms to UL Std. 61010-1, UL Std. 20751
•Low-level meter capable of displaying from 0-200 ppm of CO
•The CM-xx meets the Uniform Building Code for enclosed garages and meets OSHA standards for CO exposure
•Selectable fan and alarm relay activation
•5 A SPDT fan relay controls starters of exhaust fans
•0.5 A N.O. or N.C. alarm relay connects to warning devices or control panels
•4-20 mA Current Loop
•CM-xx mounts on a standard 4x4 electrical box and becomes cover for the box
•Supervised system: any internal detector problem will cause the fan & Alarm relay to activate
•Calibration kit is available. One screw allows access for calibration or gas test
1Where required by federal, state, local regulations or the Authority Having Jurisdiction, CM-6 and CM-12 are required to be used with Listed
Horn/Strobe model 78-2900-0211-X* to meet the 85dB(A) Audibility requirements of Standards UL 2075.
*Where “X” represents lens cover color, R for red lens cover, G for green lens cover, B for blue lens cover, O for amber lens cover, C for clear lens cover.
2.4 Specifications
•Shipping Weight: 1 pound (0.45 kg)
•Size: 4 1/2 x 4 x 2 1/8 in. (11.4 X 11.4 X 5.3 cm)
•Color: White or Dark gray
•Connections: plugs/terminals
•Mounting box: (not included) 4x4 electric
•Fan relay: 5 A, 240 VAC, pilot duty, SPDT, latching or non-latching
•Fan relay actuation: selectable at diS (disable), 15 ppm, 25 ppm, 35 ppm (default), 50 ppm or 100 ppm CO
•Fan Delay Settings of 0, 1, 3 (default), 5 and 10 minutes
•Fan Relay Minimum Runtime settings are 0 (default), 3, 5, 10 or 15 minutes
•Fan relay latching or not latching (default) selectable
•Alarm relay: 0.5A 120 V, 60 VA
•Alarm relay actuation: selectable N.O. (default) or N.C.
•Alarm relay settings: diS, 50 ppm, 100 ppm, 150 ppm and 200 ppm (default)
•Current Loop, 4-20 mA for 0-200 ppm CO, selectable to ’bAS’ (default), ‘EnH’, OFF
•Calibration Period Settings: dis(default), 3, 6, 12 and 24 (months)
•Buzzer: 85 dBA at 10cm settable to off (default) or on
•Digital display: 3-digit LED selectable to off (default) or on.
•Operating Environment: 0°F to 125° F (-18oC to 52oC),10 to 90% RH non-condensing
2.4.1 6-Series Low Voltage
•Power: 3 W (max) from 12 to 24 VAC or 12 to 32 VDC
•Current @ 24 VDC: 75 mA in alarm (two relays), 50 mA (fan relay only) and 23 mA standby
2.4.2 12-Series Line Voltage
•Power: 100-240VAC (50 TO 60 HZ)
•Current: 1.0 A MAX

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 7 |Page
3Installation Instructions
WARNING
This detector helps monitor for the presence and concentration level of a certain specified
airborne gas. Misuse may produce an inaccurate reading, which means that higher levels
of the gas being monitored may be present and could result in overexposure and cause
serious injury or death. For proper use, see supervisor or User manual, or contact Technical
Support at 1-844-325-3050.
3.1 Location
A CM-xx is normally mounted at breathing level, about 5 feet (1.5 meters) above the floor on a wall or column in a central area
where air movement is generally good. The unit, on average, can cover approximately 5,000 sq. ft. (465 sq. meters) to 7,500 sq.
ft. (697 sq. meters). The coverage depends on air movement within the room or facility. Extra detectors may be needed near
any areas where people work or where the air is stagnant. Some of the factors that affect the coverage area are application
type, personnel work areas and movement, room size, air movement, potential threat, mounting location, along with other site-
specific factors that must be considered. Please check local regulations or requirements prior to installation. The CM-xx mounts
on a 4x4 electrical box supplied by the contractor. Do not install the CM-xx inside another box unless it has good air flow
through it. Do NOT mount the CM-xx where the normal ambient temperature is below 0°F or exceeds 125°F (below -18°C or
above 52°C).
WARNING
High voltage terminals (120/240 VAC) are located within this detector (CM-12), presenting
a hazard to service technicians. Only qualified technicians should open the detector case
and service the internal circuits. Ensure power is de-energized from the detector relays
prior to servicing the unit. Failure to do so may result in electrical shock.
3.2 Installation
3.2.1 6-Series Low Voltage
1. The CM-6 mounts on a 4” square (or 4x4) electrical box supplied by the contractor. Do not mount the CM-6 inside
another box, unless it has good air flow through it.
2. Connect the CM-6 to Class 2 power supply only. It is suggested to use a separate transformer for powering the unit or
units because of possible interferences from other devices on the same power supply.
3. Connect the CM-6 to the control cables with terminal plugs. When making connections, make sure the power is off.
4. There are two terminals for Power: 12 to 24 VAC or 12 to 32 VDC, with no polarity preference.
5. There are two terminals for the dry alarm relay contacts, again with no polarity preference. The alarm relay can switch
up to 0.5 A 120 V, or 60 VA. The alarm relay is activated if gas reaches or exceeds the alarm settings. See section 4.5
Default – Factory Settings of this User manual for details on relay settings.
6. The alarm relay can be configured to normally open (default) (N.O.) or normally closed (N.C.) and will activate if the gas
concentration exceeds alarm set point. It will deactivate once the gas concentration drops below the alarm set point.
Note that the “disable” setting will cause the alarm relay not to engage at all.
7. The dry contact, SPDT fan relay has three terminals. The common (COM.), normally open (N.O.) and the normally
closed (N.C.) contact. The fan relay can switch up to 5.0 A up to 240 VAC. See section 4.5 Default – Factory Settings of
this User manual for details on relay settings.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 8 |Page
8. The Fan Relay can be configured for latching or non-latching (default) when activated (when the gas concentration
exceeds fan relay set point). Once latched in, power will need to be interrupted or the “TEST” button pressed to un-
latch the relay condition.
9. The Fan Relay will engage if the fan setting Carbon Monoxide concentration is exceeded for longer than the Fan Relay
Delay time. Unless it is configured for latching, the fan relay will disengage once both of these conditions have been
met:
•Carbon Monoxide concentration has dropped below fan setting
•Fan Relay Run time has been exceeded
Note that the “disable” fan setting will cause the fan relay to not engage. The fan relay will engage in trouble fault
condition (if the Trouble Fan Setting Option is set to “ON”) and will disengage once trouble fault condition is cleared.
10. The Current Loop is 4 mA in clean air and 4-20 mA for 0-200ppm CO
NOTE: 22 to 12 AWG wire shall be used. Wire used shall meet the temperature range of the detector i.e. 0°F to 125° F (-18°C to
52°C).
Figure 3-1 6-Series 4-20 mA Output diagram

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 9 |Page
Figure 3-2 6-Series Rear View
Figure 3-3 6-Series Alarm Control Panel diagram

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 10 |Page
Figure 3-4 6-Series DVP-120 Control Panel diagram

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 11 |Page
Figure 3-5 6-Series Multiple Device diagram
Figure 3-6 6-Series Stand Alone Diagram
Figure 3-7 6-Series Alternate Alarm Panel
In this application (above) the Fan or primary relay is used as a low-level alarm relay. The Alarm or secondary relay is used as a
supervisory relay when utilized in the normally closed configuration. The CM-6 monitors all critical functions of the unit
through software diagnostics that continually test and verify its operations. If a problem is found, the unit will switch to a fail-
safe/error mode or trouble condition. In this error mode the Fan* and Alarm relays will be activated indicating the trouble
condition at panel and the CM-6 display will flash the error. *See section 4.5.11 Trouble Fan Settings – “tFS” for options.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 12 |Page
Figure 3-8 6-Series Horn & Strobe Combo Wiring
Macurco External Horn/Strobe model number is 78-2900-0211-X, where X represents lens color, R for red lens cover, G for
green lens cover, B for blue lens cover, O for amber lens cover, C for clear lens cover. Sound pressure for Horn/Strobe model is
at least 85dB at 10 feet.
NOTE: The final installation of CM-xx system, including secondary wiring from controller to sensors shall comply with
requirements of “Class 1” in approved raceways or conduits.
3.2.2 12-Series Line Voltage
1. The CM-12 mounts on a 4” square (or 4x4) electrical box supplied by the contractor. Do not mount the CM-12 inside
another box, unless it has good air flow through it.
2. There are two terminals for the dry alarm relay contacts, again with no polarity preference. The alarm relay can switch
up to 0.5 A 120 V, or 60 VA. The alarm relay is activated if gas reaches or exceeds the alarm settings. See section 4.5
Default – Factory Settings of this user manual for details on relay settings.
3. The alarm relay can be configured to normally open (default) (N.O.) or normally closed (N.C.) and will activate if the gas
concentration exceeds alarm set point. It will deactivate once the gas concentration drops below the alarm set point.
Note that the “disable” setting will cause the alarm relay not to engage at all.
4. The dry contact, SPDT fan relay has three terminals. The common (COM.), normally open (N.O.) and the normally
closed (N.C.) contact. The fan relay can switch up to 5.0 A up to 240 VAC. See section 4.5 Default – Factory Settings of
this user manual for details on relay settings.
5. The Fan Relay can be configured for latching or non-latching (default) when activated (when the gas concentration
exceeds fan relay set point). Once latched in, power will need to be interrupted or the “TEST” button pressed to un-
latch the relay condition.
6. The Fan Relay will engage if the fan setting Carbon Monoxide concentration is exceeded for longer than the Fan Relay
Delay time. Unless it is configured for latching, the fan relay will disengage once both of these conditions have been
met:
•Carbon Monoxide concentration has dropped below fan setting
•Fan Relay Run time has been exceeded
Note that the “disable” fan setting will cause the fan relay to not engage. The fan relay will engage in trouble fault
condition (if the Trouble Fan Setting Option is set to “ON”) and will disengage once trouble fault condition is cleared.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 13 |Page
7. The Current Loop is 4 mA in clean air and 4-20 mA for 0-200ppm CO.
NOTE: 22 to 12 AWG wire shall be used. Wire used shall meet the temperature range of the detector i.e. 0°F to 125° F (-18°C to
52°C).
Figure 3-9 12-Series 4-20 mA Output Diagram
Figure 3-10 12-Series Rear View

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 14 |Page
Figure 3-11 12-Series Stand Alone Diagram

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 15 |Page
Figure 3-12 12-Series Multiple Device Diagram
Figure 3-13 12-Series Alarm Control Panel Diagram
Figure 3-14 12-Series DVP-120 Control Panel Diagram

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 16 |Page
Figure 3-15 12-Series Alternate Alarm Panel
In this application (above) the Fan or primary relay is used as a low-level alarm relay. The Alarm or secondary relay is used as a
supervisory relay when utilized in the normally closed configuration. The CM-12 monitors all critical functions of the unit
through software diagnostics that continually test and verify its operations. If a problem is found, the unit will switch to a fail-
safe/error mode or trouble condition. In this error mode the Fan* and Alarm relays will be activated indicating the trouble
condition at panel and the CM-12 display will flash the error. See section 4.5.11 Trouble Fan Setting – “tFS” for options.
Figure 3-16 12-Series Horn & Strobe Combo Wiring

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 17 |Page
Macurco External Horn/Strobe model number is 78-2900-0211-X, where X represents lens color, R for red lens cover, G for
green lens cover, B for blue lens cover, O for amber lens cover, C for clear lens cover. Sound pressure for Horn/Strobe model is
at least 85dB at 10 feet.
NOTE: The final installation of CM-xx system, including secondary wiring from controller to sensors shall comply with
requirements of “Class 1” in approved raceways or conduits.
3.3 Terminal Connection
3.3.1 6-Series Low Voltage
With the exception of the safety ground, all field wiring is completed via modular connectors (provided). After wiring, simply
plug the modular connectors into the matching connectors on the back side of the detector.
NOTE: 22 to 12 AWG wire shall be used. Wire used shall meet the temperature range of the detector i.e. 0°F to 125° F (-18°C to
52°C).
3.3.1.1 Mains Power Connection
Connect the CM-6 to Class 2 power supply only. It is suggested to use a separate transformer for powering the unit or units
because of possible interferences from other devices on the same power supply. Connect the CM-6 to the control cables with
terminal plugs. When making connections, make sure the power is off. There are two terminals for Power: 12 to 24 VAC or 12 to
32 VDC, with no polarity preference
Ensure that the wire cannot be easily pulled from the connector. Plug the modular connection into the Fan/Power connection
and ensure that it latches into the header properly.
3.3.1.2 Fan Relay Connection
All of the SPDT Fan relay terminals are available at the Fan/Power modular connector. Each Fan relay terminal normally open,
common and normally closed (NO, COM and NC) can accommodate a wire size 12 to 22 AWG. To install the wiring for the relays,
disconnect the connector from the header. Strip the insulation of each wire back approximately 1/4 in. (6.5 mm), insert the bare
wire into the terminal and tighten the screw clamp. Ensure that the wire cannot easily be pulled from the connector. Plug the
modular connection into the Fan/Power connection and ensure that it latches into the header properly.
3.3.1.3 Alarm Relay Connection
The external alarm connections (A and B) are available at the Alarm modular connector. There is no polarity for these
connections. To install the wiring for the alarm contacts, disconnect the connector from the header on the detector. Strip the
insulation of each wire back approximately 1/4 in. (6.5 mm), insert the bare wire into the terminal and tighten the screw clamp.
Ensure that the wire cannot easily be pulled from the connector. When the wires are connected seat the modular connector
into the header ensuring that the latch engages
3.3.1.4 4-20 mA Signal Connection
The positive and negative 4-20mA signal connections (+ and -) are available at the 4-20mA modular connector, a 2-position
connector. To install the wiring for the 4-20 mA contacts, disconnect the connector from the header on the detector. Strip the
insulation of each wire back approximately 1/4 in. (6.5 mm), insert the bare wire into the terminal and tighten the screw clamp.
Ensure that the wire cannot easily be pulled from the connector. When the wires are connected seat the modular connector
into the header ensuring that the latch engages
3.3.2 12-Series Line Voltage
With the exception of the safety ground, all field wiring is completed via modular connectors (provided). After wiring, simply
plug the modular connectors into the matching connectors on the back side of the detector.
NOTE: 22 to 12 AWG wire shall be used. Wire used shall meet the temperature range of the detector i.e. 0°F to 125° F (-18°C to
52°C).

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 18 |Page
3.3.2.1 Mains Power Connection
Mains connections should be done in accordance with National and Local Electrical Codes. Only qualified personnel should
connect Mains power to any device. Macurco recommends a minimum wire size of AWG18 and the wire insulator must be rated
for 140°F (60°C) service. The modular connector will accept wire from 12 to 22 AWG.
The safety ground wire should be secured to the ground screw of the metal electrical box. Tighten the screw and make sure the
wire is snug. Ensure that the wire cannot be pulled out from under the screw.
The Line (L) and Neutral (N) wires should be stripped 1/4 in. (6.5 mm), insert the wire into the ”L” and “N” wire positions of the
modular Fan/Power connector and tighten the screw clamp. Ensure that the wire cannot be easily pulled from the connector.
Plug the modular connection into the Fan/Power connection and ensure that it latches into the header properly.
3.3.2.2 Fan Relay connection
All of the SPDT Fan relay terminals are available at the Fan/Power modular connector. Each Fan relay terminal normally open,
common and normally closed (NO, COM and NC) can accommodate a wire size 12 to 22 AWG. To install the wiring for the relays,
disconnect the connector from the header. Strip the insulation of each wire back approximately 1/4 in. (6.5 mm), insert the bare
wire into the terminal and tighten the screw clamp. Ensure that the wire cannot easily be pulled from the connector. Plug the
modular connection into the Fan/Power connection and ensure that it latches into the header properly.
3.3.2.3 Alarm Relay Connection
The external alarm connections (A and B) are available at the Alarm modular connector. There is no polarity for these
connections. To install the wiring for the alarm contacts, disconnect the connector from the header on the detector. Strip the
insulation of each wire back approximately 1/4 in. (6.5 mm), insert the bare wire into the terminal and tighten the screw clamp.
Ensure that the wire cannot easily be pulled from the connector. When the wires are connected seat the modular connector
into the header ensuring that the latch engages
3.3.2.4 4-20 mA Signal Connection
The positive and negative 4-20mA signal connections (+ and -) are available at the 4-20mA modular connector, a 2-position
connector. To install the wiring for the 4-20 mA contacts, disconnect the connector from the header on the detector. Strip the
insulation of each wire back approximately 1/4 in. (6.5 mm), insert the bare wire into the terminal and tighten the screw clamp.
Ensure that the wire cannot easily be pulled from the connector. When the wires are connected seat the modular connector
into the header ensuring that the latch engages
4Operations
4.1 Power up
The CM-xx cycles through an internal self-test cycle for the first minute that it is powered. The unit will execute the test cycle
any time power is dropped and reapplied (i.e. power failure). During the self-test cycle the unit will display the firmware version
number, then count down from 60 to 0 (if the display setting is “On”) and finally go into normal operation. The alarm relay will
be activated for 10 seconds and the fan relay for 60 seconds during the power-up cycle unless the “Power Up Test” (PUt) option
is OFF. The indicator light (LED) will flash green during the self-test cycle. If 4-20mA setting is set to “EnH”, CM-xx will transmit
information related to calibration period status via 4-20mA output during power-up cycle. At the end of the 1-minute cycle, the
unit will take its first sample of the air and the indicator light will turn solid green.
4.2 Display turned “On”
Clean Air – With the display function turned “On”, the CM-xx will show the current concentration of CO ppm or “0” (zero) in
clean air.
Fan level – When the CO concentration reaches the Fan Relay setting (35 ppm, for example) the display will flash back and forth
between “FAn” and “35” or current concentration of gas.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 19 |Page
Alarm level – With the display function turned “On” and the CO concentration reaching the Alarm Relay setting, (200 ppm, for
example) the display will flash back and forth between “ALr” and “200” or current concentration of gas. The buzzer will sound
indicating “Alarm” if the buzzer is turned “On”.
Trouble – With the display function turned “On” and the device is in a trouble state, the display will display the “t” Error code
(t01 for example). If the Trouble Fan Setting is enabled, the Fan relay will switch activating the relay. See section 4.5.11 Trouble
Fan Setting – “tFS” and section 5.1.2 “t” Error Codes and
Calibration Due- With Calibration Period functionality enabled, if a detector is within 1 month of calibration period, then display
will flash back and forth between “dUE” and current gas reading. Calibration Due is resolved only with successful field
calibration.
4.3 Display turned “Off”
Clean Air – With the display function turned ”Off”, the display does not show the CO concentration. Only the Power indicator
light on will be on.
Fan Level – When the CO concentration reaches the Fan Relay setting (35ppm, for example) the display will show “FAn”
continuously as long as the fan relay is enabled. This appears as slowly flashing “FAn”.
Alarm Level – With the display function turned off the display does not show the CO concentration but will show “ALr” when the
Alarm relay is activated.
Trouble – With the display function turned “Off” and the device is in a trouble state, the display will display the “t” Error code
(t01 for example). If the Trouble Fan Setting is enabled, the Fan relay will switch activating the relay. See Section 4.5.11 Trouble
Fan Setting – “tFS” and Section 5.1.2 “t” Error Codes.
Calibration Due- With Calibration Period functionality enabled, if a detector is within 1 month of calibration period, then display
will show “dUE” continuously. Calibration Due is resolved only with successful field calibration.
4.4 4-20 mA Loop
4-20mA settings selected to ‘bAS’ or ‘EnH’ is considered as 4-20mA function turned ON.
Clean Air – With the 4-20 mA function turned “On” and the current concentration of CO ppm at “0” (zero), the 4-20mA loop will
output 4 mA.
Gas read – With the 4-20 mA function turned “On” the output will read between 4 mA and 20 mA depending on the current
concentration of CO.
Trouble – With the 4-20 mA function turned “On” and Trouble Fan Setting enabled. The 4-20mA loop will output 1 mA or 24 mA
depending on the Trouble condition. See Section 5.1 On-Board Diagnostics.

Macurco CM-xx Operation Manual
REV – 1.2.1 [34-2900-0511-6 ] 20 |Page
4.5 Default – Factory Settings
The CM-xx comes pre-programed with these default settings:
Setting:
Default:
Power Up Test
On
Display
On
Buzzer
On
Alarm Relay Setting
200 ppm
Alarm Relay Configuration
Normally Open (NO)
Fan Relay Setting
35 ppm
Fan Relay Delay
3 minutes
Fan Relay Minimum Runtime
0 minutes
Fan Relay Latching
Off
Trouble Fan Setting
Off
4-20mA
bAS (basic)
Calibration due
dIS (disabled)
To change settings, remove the Philips screw on the front of the CM-6. Pull off the front cover of the unit.
Figure 4-1 Board View
To reset the device to factory settings, see section 4.5.1 Selecting Default Configuration – “dEF
4.5.1 Selecting Default Configuration – “dEF”
To select the Default Configuration, in normal mode, push the Next button to get to “Con” or the Configuration menu. Then
push the Enter button to enter the Con menu. The first selection is the “dEF” or Default setting. Push Enter. If it is already in
Default configuration, there will be no action. If it is not already in Default configuration, “nO” will be displayed. Push Next to