nifty 170SD series Operating/safety Instructions Manual

nifty 170SD series Operating/safety Instructions Manual Manual pdf 23 page image

SD SeriesOperating & Safety InstructionsEnglish/USA 09/03 214. Operation4.1 CONTROL CIRCUIT COMPONENTS4.1.1 CONTROL BOARD: - Situated under the canopy, the encapsulated control board comprises of aPCB (printed circuit board) design which incorporates all of the relays to control the machineoperation. The control board is common to all models and contains functions which might not beutilised on your machine. A thermal trip switch is integral to the box, which protects the controlcircuit components. If power is lost, the switch can be manually reset.4.1.2 TILT ALARM: - Fitted to the top of the control board box, the tilt alarm is a solid state sensor whichmonitors the inclination of the machine. It directly controls the BRV (Brake Release Valve) and if themachine had been set up on an excessive incline would sound the alarm. Platform operation isunaffected, allowing the operator to stow the machine. This then restores the drive and it is thenpossible to drive back onto level ground, fully restoring machine operation. The tilt alarm does notoperate when the machine is being driven, as the boom switch overrides this function as long asthe booms are lowered.4.1.3 SOUNDER: - Situated beneath the PCB is a small electric sounder, which is used to provide anintermittent alarm whenever the machine is in operation. Pushing a green “power control” button ordepressing the foot switch in the cage (if fitted) will energise this sounder. This serves to warnpersonnel of the operation of the machine.4.1.4 KLAXON: - Also mounted on the top of the control board box is a klaxon, which performs severalfunctions.-Firstly, it can be used as a manual alert, by pushing the “Horn” button at the Platform ControlStation.Secondly, it is the device which sounds continuously if the tilt alarm sensor detects excessiveinclination, with the booms raised.Lastly, it is linked into the battery management system, such that when low battery state is reachedthe “pulsing” of the DC motors is mimicked by the Klaxon, re-enforcing the message to the operatorto re-charge the batteries.4.1.5 DRIVE CONTROL VALVE (DCV):- The motion control valve comprises of several individualcomponents all directly involved in the hydraulic supply to the wheel drive motors. Principalamongst these are the drive control valves, which electrically change the drive motor hydraulicsupply from series flow to parallel, or vice versa. This control function is only available when thebooms are lowered and allows the operator to select “Hi” or “Lo” drive. “Hi” drive gives fast speedof travel, but low gradeability, “Lo” drive gives best gradeability, but slow speed. “Lo” drive is usedfor climbing inclines and delicate positioning of the machine.4.1.6 BRAKE RELEASE VALVE (BRV):- The motion control valve also incorporates a solenoid operateddump valve which controls the brake function on the machine. This valve must be energised toallow the machine to move. If no voltage is present, the wheel motors will not be able to developdrive torque, whilst at the same time, the spring applied parking brakes will remain engaged. Onlywhen the green “power control” button is being used (or the platform foot switch is depressed) willthe BRV operate. If the tilt alarm sensor detects an excessive inclination whilst the booms areraised, it is the BRV which is de-energised to isolate the machine (at the same time the Klaxon tonechanges to a continuous one to indicate this condition).