Instruction Manual

Component Identification

512.14 Hydraulic Power Unit Introduction

Component Descriptions

Component Description

Control Box

Houses the electronic controls of the pump, including the Stop button, and

Low/High switch. It also houses the thermal overloads to protect the pump

motor. See “Resetting the Thermal Overloads” on page 24.

Pressure Gage

Shows the current output pressure from the hydraulic power unit. The output

pressure is factory set to 21MPa (3000 psi). See “Adjusting the Output

Pressure” on page 25 to change the output pressure.

Sight Glass

Combines a thermometer with a sight glass. You can quickly check the

hydraulic fluid’s temperature, level, and condition (by its color).

Reservoir

Stores the hydraulic fluid. The reservoir has a 57 L (15 gal) capacity. It

includes a magnetic drain plug to help catch metal particles.

Heat Exchanger

Cools the hydraulic fluid. The heat exchanger can be either water-cooled or air-

cooled. See “Adjusting the Air Flow” on page 22 and “Adjusting the Water

Flow” on page 23 for more information.

Filter

Provides 3–micron filtration to fluid returning to the reservoir (see “Replacing

the Filter” on page 31).

Low Fluid and

Overtemperature Sensor

(Not shown) Shuts the pump off if fluid gets too low or becomes hotter than

75ºC (160ºF). See “Reducing the Fluid Temperature” on page 21 or “Adding

Hydraulic Fluid” on page 35 for more information.

Filter Change Gage

Shows when it’s time to change the hydraulic filter. The gage is marked with

three zones; green, yellow, and blue.

Green—The filter is good to use.

Yellow—Change the filter soon.

Red—Do not run the HPU until you have replaced the hydraulic filter element.

Pump Motor

Drives a fixed displacement gear pump.

Pumps a 12.5 lpm output at 21 MPa (3.3 gpm at 3000 psi) @ 50 Hz.

Pumps a 15.1 lpm output at 21 MPa (4 gpm at 3000 psi) @ 60 Hz.