Two-Step Electro-Hydraulic
Brake Package for Cranes

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The Two-Step Electro-Hydraulic Brake Package makes converting an Electric Overhead Traveling (EOT) Crane from cab control to radio remote or pendant control easy. The conversion requires changing the operation of the bridge brake from a foot pedal to an electrically operated brake. With the Two-Step Electro-Hydraulic Brake Package, the existing foot pedal system remains in place, and there is no need to re-size or change the existing manual brake system. This eliminates the chance for error in sizing a totally new brake and potential damage to the mechanical structure of the crane during installation of the new brake.

Flexibility

Two-Step Electro-Hydraulic Brake Packages are designed to be installed in parallel with an existing manually operated, cab-mounted, hydraulic foot brake. Several available configurations allow for use with a variety of crane power sources, such as 110, 220, and 440 VAC, and 250 VDC. Brake operation can be controlled by any Cattron-Theimeg Portable Remote Control systems, as well as by pendant. The standard brake package offers two (2) adjustable steps of brake application and a brake release function, thus providing the operator with precise control of the crane brakes without unnecessary load sway due to abrupt stopping. A parking brake release function for a Wagner™ HM parking brake is optionally available (PKK) model. An optional three (3) step package is also available by special configuration of the PKK brake model.

Adjustability

The Two-Step Electro-Hydraulic Brake Package is adjustable and can be tailored to meet your crane size, load size, and stopping distance requirements. The system includes a long-life hydraulic pump, driven by a continuous duty electric motor. The pump develops the required brake pressure; the pressure is then held in the accumulator storage chamber, where it is ready for application to the brake cylinder upon command. When applied to the brake cylinder, the pressure varies, depending upon which electric valve is actuated and its associated pressure relief setting.

Each step of braking is independently adjustable to correspond directly to the operator's stopping rate requirements. The amount of brake application pressure is selected by the portable remote control or pendant operator. Normally, a soft brake is automatically applied when bridge control is brought to neutral. When faster stops are required, hard brake pressure is selected with a push-button on the portable remote or pendant remote.

Safety

When properly installed and interfaced with the crane's control circuits, the brake systems will not permit the movement of the crane unless brake pressure is above a minimum level necessary to stop the crane. Any loss of power applies accumulated brake pressure to the brake cylinder. This provides brake pressure even when the crane power is turned off.

Additional Features

• Cost Effectiveness: Bypasses the intermediate pneumatic step used on some current braking systems, thus reducing cost and improving reliability without sacrificing safety.
• Single Panel Mounting: The brake assembly, minus the motor and pump, is mounted on a single panel, in a pre-wired, plumbed, and tested NEMA 12 enclosure. Only three (3) hydraulic connections are required for a complete installation. An optional NEMA 4 or NEMA 4X (IP66) cabinet is recommended for severe environments (acidic fumes, salt water, etc.) to further guard against damage.
• Step- Down Transformer: All AC systems operate on 110 volts; therefore, the appropriate step-down transformer is provided as part of the system when requested.
• Shuttle Valve: All BP 102 and BP202 brake packages work in conjunction with the manual foot brake existing on a crane. The manual system must remain operational; therefore, a hydraulic shuttle valve is included to automatically select either foot pedal operation or radio operation, without interaction between the two.
• Pressure Gauges: Two pressure gauges are provided to monitor the brake cylinder line and pressure stored. This allows ease of adjustment and a visual indication of the different increments of braking while monitoring the system operation. The second gauge shows the stored charge in the accumulator, which must be present to stop the crane in case of pump failure.
• Filter: A spin-on, in-line brake fluid filter is built into this system to catch any small amount of debris which would cause possible valve failures. This filter is easily disconnected and cleaned without disturbing system piping. It has a service gauge to indicate when the filter should be replaced.
• Custom Valve Manifold: A specially designed, single block manifold for significantly reducing the amount of pipes, fittings, and hoses, and increasing reliability and ease of maintenance.
• Portable remote or Pendant Conversion: The BP 102 and BP 202 Electro-Hydraulic Brake Packages can be used for converting an existing EOT to either a portable remote control or pendant control operation.
• Temperature: All parts used in the Two-Step Electro-Hydraulic Brake Package can withstand temperatures at or below 158ºF (70ºC). Both the valves and the motor have been rated at that temperature for continuous operation. This means that the brake system is operational for cranes used above furnaces and in other high temperature environments where the ambient temperature does not exceed 158ºF (70ºC). Outdoor operations are good at low temperatures because there is no air compressor and no frozen water that is inherent with electro-pneumatic systems.
• Pressure Release Valve: This provides an easy method of releasing fluid from the brake panel after transferring from radio to manual operation. It also simplifies maintenance; the valve is electrically operated and normally ties into a remote/manual selector switch.
• Accumulator: The accumulator is a storage device which will provide a source of pressure should the pump become inoperative. The pre-charge inlet requires no special tools to apply pressure or to check the pre-charge. It has a special stirred valve (like that on an automobile tire), making a tire pressure gauge all that is required to check the pre-charge pressure.
• Brake Fluid Compatibility: All components are designed for use with DOT-3 brake fluid, the type suggested by the manufacturers of most existing and new manually-operated foot pedal type brake systems.
• Multiple interfaces: The Two-Step Electro-Hydraulic Brake Packages interface directly to a variety of control applications. They can be used on any remote control crane, and with multiple voltages, such as 110, 220 and 440 VAC or 250 VDC. A user can upgrade an existing crane at any time and can easily interface into any portable remote control or pendant system.
• Available configurations:
• 110 VAC, 2-step brake
• 220/440 VAC, 2-step brake
• 250 VDC, 2-step brake
• 110 VAC, 2-step brake plus parking release
• 250 VDC, 2-step brake plus parking release