MTS Systems SilentFlo 505G2 Series, Руководство пользователя

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Introduction
Series 505G2 SilentFlo™ Hydraulic Power Unit 19
Heat exchanger
Hydraulic fluid temperature is maintained with a heat exchanger that cools the fluid. The water-cooled
heat exchanger cools the hydraulic fluid as it passes over water-filled plates. A regulating valve
monitors the temperature of the hydraulic fluid and adjusts the flow of water through the plates. The
flow of cooling water regulates the temperature of the hydraulic fluid.
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The typical operating temperature range of the hydraulic fluid is
43–49°C (110–120°F).
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If the hydraulic fluid temperature exceeds 55ºC (131ºF), a switch opens and shuts down the
HPU.
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When the HPU is shut off, the flow of water is also stopped by a shutoff solenoid valve.
Note: For additional information see the Heat Exchanger Care and Water Quality Guide (part
number 015-164-000).
Auto-Cooling Valve (adjustable)
The auto-cooling function is integrated into the control manifold. During periods of low flow demand
from the external hydraulic circuit, this feature provides two important benefits: a re-circulating flow that
ensures hydraulic fluid filtering whenever the unit is on, and safeguarding against hydraulic fluid over-
temperature. It functions by opening a hydraulic flow path through the fluid conditioning circuit when
external hydraulic demand for flow is low. When the external demand increases, this feature closes the
path to provide the full flow of the HPU to the external demand.
The effective operating range of the auto-cooling circuit is between system pressures of 14 MPa (2000
psi) to 21 MPa (3000 psi). In order for the Auto-Cooling Valve to function properly, it must be re-
adjusted anytime the output pressure will be changed for longer than 10 minutes.
Note: If the test condition requires a maximum pressure level less than 14 MPa (2000 psi),
consult MTS.
Electrical Control
The HPU can be controlled locally using the front panel controls, or remotely through a controller. A
PLC (programmable logic controller) manages the electrical systems within the HPU. The controls
included in the electrical enclosure include the following:
A user interface panel that contains a touch screen to program preferences and operational settings.
The screens on the user interface panel provide quick indication of the unit’s condition, including
motors status, running time displays for each motor, hydraulic fluid level and temperature, and filter
condition.
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Wye-delta starting reduces the initial current rush when the motor starters are engaged.
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Thermal overloads protect the individual HPU motors from excessive current draw.
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A latchable Emergency Stop button prevents inadvertent starts.
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Interlocks protect the HPU against low hydraulic fluid level, overtemperature, and dirty filters.