Welder User Manual
67 
 AUTOMATIC CO
2
 CYLINDER CHANGEOVER 
An automatic CO
2
 cylinder changeover system (MCO-21GC) is available as an optional accessory. This 
system switches the gas supply lines when one CO
2
 gas cylinder becomes empty. 
Note: The installation of the MCO-21GC must be performed only by qualified service personnel. 
Install the MCO-21GC and then perform the following procedure 
1. Connect 2 gas tubes to connecting ports A/B for CO
2
 gas pipe. Connecting ports for CO
2
 gas pipes are 
located on the left back of the Incubator. (Refer to page 9). 
Note: Only port A can be used when the MCO-21GC is not installed. There will be 2 ports, ports A and B, 
after the MCO-21GC is installed. 
2. Connect a CO
2
 gas cylinder equipped with a gas pressure regulator to each gas tube. Refer to page 16 
for information on connecting the gas cylinders. (“Gas cylinder A” is the CO2 gas cylinder connected to 
the connecting port A for CO
2
 gas pipe, and “gas cylinder B” is the CO2 gas cylinder connected to the 
connecting port B for N
2
/O
2
 gas pipe.) 
3. Open the valves of both gas cylinders. 
4. The current CO
2
 gas supply line is displayed on the Top Display. 
(“A” and “B” will be displayed only when the MCO-21GC is installed. Nothing will be displayed if 
MCO-21GC is not installed.) 
5. The MCO-21GC detects that there is no more CO
2
 gas in a cylinder when the CO
2 
density in the 
chamber does not increase for a while even after opening the CO
2
 gas valve in the Incubator. It switches 
the gas supply line when it detects that there is no more gas. At that time, the following indications of 
switching the gas cylinder are provided. 
Message display field  Display of gas supply 
When CO
2
 gas supply line switches 
automatically (Only when MCO-21GC 
is installed) 
Err01: CO
2
Gas Empty is 
displayed. 
The character for gas supply line 
that is empty blinks. 
The gas supply line that is 
currently being used is displayed 
in reverse video. 
●To silence the buzzer, press the BUZZER Key. The alarm condition is cleared and normal operation 
continues. 
Current CO
2
 gas supply line 
 5 .
1 
T e m p    3  7  .  0
o 
C   C O 2   5 . 0 %   A B  O 2  5 . 0 %  A   B
2 
3 
4 
5 
     S t a t u s    
6 
  O K    
7 
37.0 
 5.0 
 5.0 










