Hardi ALPHA 2000, Instruction Book

Page: 47 / 52

47
ALPHA
Fault Probable cause Control / remedy
EC Operating unit
Operating unit not Blown fuse(s). Check mechanical function of microswitches.
functioning Use cleaning/lubricating agent if the switch
does not operate freely.
Check motor. 450-500 milli-Amperes max.
Change motor, if over.
Wrong polarity. Brown - pos. (+). Blue - neg. (-).
Valves not closing properly. Check valve seals for obstructions.
Check microswitch plate position. Loosen
screws holding plate a
1 /
2
turn.
No power. Wrong polarity. Check that brown is pos. (+),
Blue is neg. (-).
Check print plate for dry solders or loose
connections.
D.A.H. Hydraulic system
No boom movements Insufficient oil pressure Check oil pressure - min. 130 bar, max. 150 bar.
when activated
Check hydraulic oil level
Insufficient oil supply. Check hydraulic oil level.
Blown fuse. Check / replace fuse in junction box.
Bad / corroded electrical connections Check / clean connections, etc.
Insufficient power supply. Voltage on activated solenoid valve must be
more than 8 Volts. Use wires of at least 4 mm
2
for power supply.
Defect relay / diodes in junction box. Check relays, diodes and soldering at PCB in
junction box
Wrong polarity. Check polarity. White pos. ( + ) Blue neg. ( - ).
Individual ram Clogged restrictor Dismantle and clean restrictor
does not move