MTS Series 298 Hydraulic Service Manifold - Manual (Page 17)

Functional Description
Series 298 Hydraulic Service Manifold Introduction 17
Functional Description
The Series 298 Actuator Manifold contains the required porting for single or dual
servovalves, two accumulators, and an actuator (see
“Component Identification”
on page 7). The hydraulic schematic shows the Model 298.10 with darker lines.
The additional components for the Model 298.11 and Model 298.12 are also
shown. Any Series 298 Actuator Manifold can be changed to become another
model. The hydraulic pressure to the actuator manifold is controlled by the
hydraulic controls on the system controller.
Filter The optional filter prevents contamination of the servovalve(s). A 3- or 10-
micron (absolute) inlet filter may be added to the actuator manifold. This filter
prevents the passage of dirt particles that might enter the system as a result of
opening hydraulic lines and adding hydraulic fixtures. A differential pressure
switch is mounted across the filter to provide a visual indication of a dirty filter
condition. A differential pressure switch with an electrical output may be used to
send a signal, indicating a dirty filter condition, to your controller. This requires
an additional cable and special connections to the controller.
Accumulators
The Series 111 Accumulators suppress line-pressure fluctuations. The
accumulators thread directly into the actuator manifold (one-pint or onequart size
accumulators can be used). The pressure-line accumulator provides fluid storage
to maintain a constant line pressure at the servovalves for maximum
performance. The return-line accumulator minimizes return-line pressure
fluctuations. The Series 111 Accumulators are piston-type accumulators. Other
piston- or bladder-type accumulators may be used. Contact MTS for more
information.
Ports
The Series 298 Actuator Manifold contains the required porting to accommodate
single or dual servovalves, and servovalves with four or five ports. For one
servovalve, the mounting ports for the second servovalve are covered with a
plate. When two servovalves are used, they operate in parallel. This increases the
flow capacity of the actuator manifold to a maximum of 114 L/min (30 gpm). If
the system requires a four-port servovalve, a blocking plate is used to cover the
fifth port.
On/off solenoid
The Model 298.11 Actuator Manifold contains an on/off solenoid valve to apply
and remove full system hydraulic pressure to the servovalve(s). The on/off
solenoid controls a high pressure poppet which applies the hydraulic pressure to
the servovalve ports. However, high pressure is always available at the pilot
pressure port (for servovalves that support pilot pressure).