Graco BetaCell 241D, Операция

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To protect against a mechanical failure of the valve, an electric over
pressure switch, factory set to 2800 psi is installed in the pressure line.
This limit switch will shut down the hydraulic motor and be accompanied
by audible and visual alarms. In this case, the directional valve defaults to
the gun CLOSED position and the accumulator pre-charge automatically
closes the gun.
A low-pressure switch, factory set to 1500 psi descending, is also provided
to prevent failures in the event the hydraulic pressure is not sufficient to
open the gun. This limit switch will prevent the gun from opening and be
accompanied by a NOGO on the gun status indicator.
A second major component in the system is the directional valve that
diverts flow to the open or closed position in the gun.
The location of the directional valve plays an important part in the overall
performance of the system and as a general rule it should be located as
close to the gun as possible taking into account the length of the hoses and
the duty cycle. For a moderate duty cycle and hose lengths of less than 50
feet, location directly on the PowerPack manifold will provide satisfactory
performance. For operation outside this range, an optional remotely located
manifold is available.
The location of the directional valve is the
responsibility of the customer and should be decided upon only after
consultation with Gusmer.
The success of any hydraulic system is dependent on the quality and
maintenance of the hydraulic fluid. A return line filter with a servicing
gage is provided to maintain the fluid and assure the reliable operation of
the unloading and directional valves.
IMPORTANT: 1. Use only recommended hydraulic fluids.
2. Determine that the manual unloading valve is fully closed during
operation to prevent excessive heating of the hydraulic fluid.
3. Periodically change the hydraulic fluid and filters in accordance to the
schedules provided in the Maintenance Manual.
4. Do not subject the unit to a service factor that it is not designed for.
5. Always unload the accumulator pressure to zero with the manual
unloading valve before performing any maintenance on the hydraulic
system.