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5. Mounting
Clean all the pipes before mounting the valve and completely remove dust, scale and other foreign
matter. Mount the transfer valve as close to the actuator as possible and let air flow toward the IN and
OUT marks located on the lower side of the body.
Two EXH ports are provided. Use one EXH port and put a blind plug in the other unused port. When
using the valve as a lock-up valve, put a blind plug each in the two EXH ports.
Two air connection ports to the pilot part are provided on the 78-80H, one being marked SIG and the
other, SIG OUT. Connect the signal pressure to the port marked SIG. Use SIG.OUT for sending signal
to the 08-80H when it is also mounted.
The transfer valve functions to cut off IN and to connect OUT to EXH when the signal pressure lowers
below the set pressure or is reduced to zero.
Do not use signal pressure at air pressure exceeding 1.03Mpa (10.5kgf/cm2).
Feeding signal pressure from near the IN side of the body will cause fluctuations in signal and air
pressures due to the large air valve capacity. This may cause hunting.
6. Adjustment
The necessary settings of the transfer valve are generally performed at the factory and adjustment of
it is not required. If, however, the setting pressure needs to be adjusted, make adjustment as follows:
a) Loosen the lock screw (26) and turn the adjust knob (17) counterclockwise to release the
compression of the spring (25).
b) Turn the adjust knob (17) one or two turns clockwise to tighten it and to slightly compress the
spring (25).
c) Connect air pressure to “IN” marked on the body to check whether the body is open or closed.
Then connect the pressure gauge and pressure reducing valve to the signal pressure connection port
SIG.
d) Apply supply air pressure and set the air pressure to SIG at specified pressure by operating the
pressure reducing valve while watching air pressure to SIG on the pressure gauge.
e) Turn the adjust knob (17) clockwise until air pressure no longer leaks through “OUT” marked on the
body.
f) This will cut off IN, and OUT and EXH will open in the transfer valve.
g) Lastly, fasten the lock screw (26) and fix it.
The ball (21) temporarily floats to transfer the pilot part and the valve emits a light beat tone
when the set and signal pressures become the same. This is not an anomaly. The beating
sound will stop when the transfer ends.
