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Masoneilan 77-80H/00-80H Air Valve Instruction Manual | 7
1. Outline
The 77-80H, an air valve that consists of a combination of pilot valve and three-way valve,
is a high-capacity "set pressure control" type three-way valve.
Besides this, there is the 00-80H, the so-called three-way valve - the 77-80H from which
the pilot valve is removed.
In case a plurality of 77-80H valves are needed, use one 77-80H valve and 00-80H
valves for the rest and connect the outlet pressure of the 77-80H's pilot valve to "SIG" of
each 00-80H valve. By so doing, not only piping is simplified but also change-over can be
made simultaneously.
2. Specification
Item
Standard
Option
Max Operating
Pressure
Body
880 kPa
－
Signal
1030 kPa
－
Set Pressure Range
100
– 700 kPa
－
Hysteresis
<= 34 kPa
－
Cv Value
IN
→ OUT
4.56
－
OUT
→ EXH.
4.25
－
Connection
IN, OUT, EXH.
Ports
Rc1/2
½ NPT
SIGNAL Port
Rc1/4
¼ NPT
Operating Temperature Range
-30 to +70
℃
-18 to +100°C (High Temp)
-49 to +80°C (Low Temp)
Housing Material
Aluminum Alloy
－
3. Installation
Prior to installing, clean all lines thoroughly to remove all dirt, scale or other foreign
matter.
Install the air valve as near the actuator as possible, holding the number of connections
to a minimum, so that the air flows in the direction indicated by the marks,
”IN" and "OUT"
on the underside of valve body. There are two "EXH" ports. Use the necessary one and
pipe plug the other. When the valve is to be used as a lock-up valve, the both ports must
be pipe plugged.
The signal pressure piping should be made by connecting the supply pressure directly to
"SIG. IN" so that when the air pressure drops below the set pressure or disappears the
air valve operates to close "IN" and connect "OUT" and "EXH
”.
Do not use for air pressures exceeding 880 kPa.
Be careful not to take the signal pressure from near the "IN” side of body because
due to the large capacity of the air valve this gives rise to a change in signal air
pressure, thereby causing hunting.
