Koso REXA Electraulic Xpac, Инструкция по установке и эксплуатации

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REXA
Electraulic Actuators & Drives
Xpac
Installation Manual -- Version 5.1 (5/08)
G-3
G. ACCUMULATOR FAILURE
G.1 Description of Operation
G.1.1 OPERATION
System operation is based on a piston type accumulator with nitrogen
gas on one side of the piston and oil on the other. The accumula-
tor is sized to provide a minimum of 2000-PSI oil pressure to the
cylinder during failure, thus insuring that the actuator will always
produce its rated output.
Upon loss of electric power or receipt of a trip signal, two solenoid
valves open simultaneously, one allowing oil under pressure from the
accumulator to enter the failure side of the actuator and the other
allowing the oil displaced from the opposite side of the actuator into
a holding reservoir (auxiliary cylinder).
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When the trip signal ends or power is restored, a pressure transducer
signals the PCP of low pressure in the accumulator. This signal tells
the PCP to open both solenoids and run the power module in the
direction required to drive the actuator in the fail direction. As the
actuator is already at the end of travel in the fail position, oil will be
drawn from the reservoir and pumped into the accumulator. When
the proper recharge pressure is reached, the PCP stops the power
module and closes the solenoid valves. Normal operation is now
resumed.
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