Abacus Lighting, Sutton-in-Ashfield, Nottinghamshire, NG17 5FT, England. Tel: (+44) 01623 511111, www.abacuslighting.com
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Slightly raise the flow control valve end of the rams and fully close.
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The ram can then be returned to the trolley.
Check that the flow control valve is functioning correctly. This is accomplished by extending the
ram about 300mm then retracting it. During retraction the reading on the pressure gauge should
not be less than 1000psi. The pressure will increase to the relief valve pressure of 2500psi
(1750psi for pre 2003 units) as the end of the stroke is reached.
Ensure that the upper and lower ram anchor pins and are present and undamaged. The correct
pins are colour coded as shown in the table above.
Check that the relief valve pressure is correctly set at 2500 ± 100psi or for pre 2003 units 1750 ±
100psi, by operating the control valve to retract the rams when they are already fully closed. The
pressure should rise quickly and stabilise at the correct value. If the reading is incorrect adjust the
pressure relief valve setting as follows:-
The relief valve is located below or adjacent to the control valve. Some valves are fitted with a
screwed cap which must be removed to allow the adjustment to be made. Hold the centre
adjusting screw with an Allen key and slacken the locknut. With the ram fully closed, operate the
control valve such that the relief valve pressure can be read on the pressure gauge. Turn the Allen
key clockwise to increase the relief valve pressure and anticlockwise to decrease it. When the
correct reading has been obtained, tighten the locknut and recheck the pressure setting. Refit the
screwed cap if provided.
Examine the hydraulic ram, in particular the area around the seal, for any signs of damage and oil
leakage. Fully extend the piston rod and check the polished surface for signs of bruising and
corrosion pitting. Either will cause failure of the gland seals.
Check that the wheels on the unit are operational and retained in position. The tyres should be
fully inflated to a maximum pressure of 32psi.
DO NOT USE THE UNIT UNLESS ALL THESE CHECKS ARE SATISFACTORY.
IN THE EVENT OF DAMAGE TO COMPONENTS OR FOR FURTHER ADVICE CONTACT THE
ABACUS TECHNICAL DEPARTMENT AT THE ADDRESS BELOW.
