Kele KCO-NO2, User Manual

KCO-NO2  User’s  Manual 

90-0201-01 

Kele • 3300 Brother Blvd. • Memphis, TN  38133

Page: 6

WWW.KELE.COM 

3  Electrical Installation 

The controller is not equipped with a power switch; it is operational whenever sufficient power is 
applied to the low voltage power input terminals (do not connect to line).   
All electrical connections to the controller are made through screw terminals that can be unplugged 
during wiring.  The controller’s enclosure contains multiple conduit knockouts for flexibility during 
installation; refer to Figure

 2

 and Figure

 1

 for details and dimensions of the enclosures. 

3.1  Analog Reporting-Output Connections 

Each sensor’s readings are individually reported by the 
controller’s two powered 4-20mA analog output 
connections.  Current flows out of the ‘+’ terminal and 
returns to the ‘-‘terminal. 
The CO output is provided at the terminals highlighted 
green in Figure 3 and the NO

2

 output is provided at the 

terminals highlighted yellow in Figure 3.  The analog 
output connection has polarity as labeled on the controller 
silkscreen: care must be taken to ensure proper 
connection.  To wire the analog output connections: 

1.

Power down the controller,.  This can be done by 
unplugging the controller power terminal  
(See Figure 6

).

2.

Unplug the desired analog output screw terminal (either the NO

2

 or CO terminal). 

3.

Connect the signal wires paying close attention to the polarity.  

4.

Plug the analog output screw terminal back into the controller. 

5.

Repeat this process for both analog outputs, then reconnect power.  

3.2  Relay Connections 

The controller has two SPDT dry-contact relay output terminals (shown in Figure 4).  The relays are 
UL rated at 10 Amps at up 277 VAC, and the associated circuitry meets UL criteria for connection 
to line voltage below 300 volts.  Some jurisdictions may require such heavy gauge wires that the 
full capabilities of the relays are not operationally 
achievable. 
The relay connections have three-terminal screw 
connectors that allow devices to be wired to the 
controller in either normally-open (

NO

) or normally-

closed (

NC

) configuration.  These outputs are activated 

when ambient air concentrations rise above the 
controller threshold settings (refer to 

Section 4.3

 for 

more information). 
In the 

NO Configuration

, the voltage attached to the 

NO

terminal will be present at the 

COM

 terminal only when 

the relay output is activated. 
In the 

NC Configuration

, the voltage attached to the 

NC

terminal will be present at the 

COM

 terminal while the 

relay output is deactivated: the voltage attached to the 
NC terminal is removed when the relay output is activated. 

Figure 4: Relay Outputs 
 

FIGURE 3

: Location of Analog Output 

Terminals

.