59
GAS AUTO-CHANGER (OPTIONAL)
When the optional gas auto-changer MCO-21GC is installed, there will be two connecting ports for the CO
2
gas pipe: A and B. When two CO
2
gas cylinders are connected, the auto-changer switches the CO
2
gas
supply line when one of the cylinders becomes empty.
Connecting CO
2
gas cylinders
Refer to page 20 for the procedure for connecting gas cylinders.
1.
Take two CO
2
gas cylinders (A and B) and install the optional gas regulator MCO-010R on both.
2.
Using one of the gas tubes provided, connect the
gas regulator of cylinder A to connecting port A.
3.
Using another gas tube, connect the gas
regulator of cylinder B to connecting port B.
Automatic CO
2
gas supply line changeover
When the optional gas auto-changer MCO-21GC is installed, CO
2
gas supply line indicators A and B and
the CO
2
gas supply line select key will be displayed on the Top screen. A light will show which CO
2
gas
supply line is being used (see page 14).
When the CO
2
density level remains unchanged, even though the CO
2
gas valve in the unit is open, the
unit regards the currently connected CO
2
gas cylinder as empty. The CO
2
gas supply line is changed over
automatically. The process is set out in Table 2.
1.
When there is gas remaining in cylinder A, the unit operates with gas supplied from cylinder A
(Situation
1
).
2.
When cylinder A is empty, the level of CO
2
density in the unit does not increase because gas is not
supplied into the unit even though the gas valve in the unit is open (Situation
2
).
3.
When Situation
2
continues for 2–3 minutes, the gas supply line is changed over automatically. The CO
2
gas empty alarm is activated sounding the buzzer, and gas supply indicator A is displayed in reverse video
and blinks (Situation
3
).
4.
Stop the CO
2
gas empty alarm by pressing “Buzzer”. The light on gas supply indicator A is turned off
(Situation
4
).
Connecting port A for CO
2
gas pipe
Lower right side
Connecting port B for CO
2
gas pipe