Advanced Braking Unit
Buying Systems and buying loose components
When purchasing a “Complete system” the equipment is supplied WITH the required brackets for the initial installation. When purchasing “individual” components, these components are supplied WITHOUT the necessary “first time installation” accessories.
Advanced Braking Unit Component Description
Indicates the hydraulic fluid level in the tank.
Part number: ARHYD 041
16 Way Connector
This plug provides connection between the pump starter and the brake unit. The pump starter controls the start stop of the system and interfaces with the controller. The system is designed to operate with various controller types.
Part number: ARHYD 056 & AR800T 050
For the correct installation consult with the Loco Manufacturer.
Once the brake system has been installed correctly, the following guidelines should be adhered to.
- Ensure hydraulic oil reservoir is filled with 46 /68 Hydraulic, or SAE 15W50 multi grade oil.
- Care must be taken not to over fill the reservoir. Allowance should be made for oil in the cylinder to return to the reservoir when the cylinders go to the normal position.
- The level gauge should indicate the oil level just above half.
- Never use contamminated oil.
- Any spilled oil must be cleaned to prevent slip and fall incidents.
- Ensure the cylinder hoses are connected and start the pump to remove air from the system.
- Top up oil in the reservoir, if required.
- How to determine brake holding power:
- a. Ensure that the Loco has a full span of hoppers.
- b. Position the vehicle at the worst gradient on the specific level.
- c. Measure the required current to hold the vehicle stationery.
- d. Add 20% to the holding current and use this as the criteria to test the brakes holding ability.
- Flow control valve
- a. The flow control valve is pre-set at the factory and does not need to be adjusted.
- b. Adjusting the flow control valve incorrectly might lead to having no flow at all and resulting in the cylinders not applying or releasing.
- c. DO NOT ADJUST THE FLOW CONTROL VALVE
- Emergency Dump valve.
- When the Emergency Dump Valve is depressed it simultaneously activates the limit switch that in turn disables the controller.
- Ensure that there is no pressure build up when the dump valve is pressed and the motor runs. Should there be a pressure build, please investigate and make sure that the aluminium arm that activates the limit switch is set correctly – see picture below
- The distance between the nut and the shoulder of the Emergency Dump Valve must not be less than 7mm, as this can prevent the Emergency Dump Valve from open completely.
Store cylinders in an upright position. *OEM cylinder service is recommended annually.
The cylinder is a spring applied hydraulic release or a fail to safe type. The cylinder is a positive displacement type. The cylinder stroke is ±100mm and a threaded adjustment rod is fitted to the cylinder so as to facilitate easy adjustment. A single entry for the hydraulic connection is supplied. A serial number is punched on the rear of the cylinder for batch identification. A clevis pin and split pins are supplied as well as a nut, half nut and washers for mounting and adjusting.
Part number: ARHYD 002 –
Maintaining the System
- Always ensure that the system has enough oil, oil level gauge indication above half should be sufficient.
- Check and repair any oil leaks.
- Ensure the pressure switch settings are correct, 6,5Mpa stop and ± 5,2Mpa restart.
- Ensure pressure relief valve is set so that the system pressure does not exceed 8Mpa.
- Test the electrical interlocks:
- Emergency dump limit switch.
- Manual pressure switch.
- Differential pressure switch.
- Regularly test the manual pump operation. (at least 30 day intervals recommended.)
- Regularly test the Emergency dump valve operation. (at least 30 day intervals recommended.)
- Ensure all electrical connections are secure.
- Regularly inspect the oil level and top up when necessary. Use correct grade oil and do not allow oil contamination.Replace filler caps properly.
- The brushes should be examined after a 1000 hours running time or at intervals of three months, whichever is the shorter period. Brushes worn to a length of 10mm or worn to the wear line should be replaced. Accumulation of carbon dust on the brush holders and on the mounting ring should be extracted using a suitable dust extraction unit. New brushes should be checked for freedom of movement in the brush holders, and should be bedded to the curvature of the commutator using a fine grit glasspaper.
- Test brake holding power at least once per shift, the brakes should hold the loco in place at the current as determined in “The installation Guidelines” paragraph 8 If not check, correct brake adjustment. Replace worn brake shoes if required.
- Remove cylinder clevis pin to replace brake shoe, do not pressurise cylinder. Sudden loss in pressure will cause injury.
A breakdown might require that a loco needs to be towed. There are certain safety measures that must be adhered to. The following guidelines will minimise the chances of accident occurring.
- Before the broken down loco’s brakes are released, ensure that the loco has been coupled to the towing loco. This is to ensure the loco does not accidentally move when the brakes are released.
- When the brakes are released either by the Brake release key or the Manual pump ensure that the controller is disabled, it must not be able to drive under own power.
Before unhitching from towing vehicle apply brakes to loco by depressing the Emergency dump valve.