Mohawk V-035-A-X, Operation And Maintenance Manual

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MV-A00000920 MOHAWK V-A SERIES: VERTICAL RISE DRIVE-ON MANUAL 35,000 - 64,000 LB MODEL 6-9
6.4. Abnormal operation
WHAT HAPPENS WHERE CHECK
The lift does not rise and
the motor does not start
a. FUSES
b. THERMAL RELAY
c. TRANSFORMER
d. MOTOR
e. CONTACTOR
f. PHOTOCELLS
a.1. line fuse blown.
a.2. 24-volt fuse blown.
b.1. thermal relay tripped, re-cock.
c.1. transformer burnt out, does not emit 24 volt.
d.1. motor short-circuited or burnt out.
e.1. contactor C1 burnt out
f.1. photocell fault.
f.2. photocells out of reading range
The lift does not rise and
the motor starts.
a. HYDRAULIC PUMP
b. DISCHARGE VALVE
c.
LIMIT VALVE
d. MOTOR
a.1. o-ring seal broken.
a.2. key broken.
a.3. aspiration tube broken.
a.4. clamping screws loose.
a.5. check oil leakage.
a.6. check the pressure value
b.1. EV1 remains open.
c.1.limit valve broken.
d.1. Check that the motor turns in the direction shown by the arrow.
The lift does not lower and
the pressure is normal.
a. PHOTOCELLS
b. TRANSFORMER
c.
HYDRAULIC VALVE
d. ELECTRIC VALVE
e. MECHANICAL SAFETY
DEVICES
f. AIR VALVE
a.1. photocell fault.
a.2. photocells out of reading range
b.1. transformer burnt out, does not emit 24 volt.
c.1. EV1 blocked.
c.2. check the parachute valves on the bottom of the dual effect cylinders.
d.1. EV1 24 V coil burnt out.
e.1. mechanical safety devices mechanically blocked.
f.1. EV2 air blocked (does not open the mechanical safety devices).
f.2. EV2 requires power.
The lift rise not levelled
a. CYLINDERS
b. VALVES
a.1. air in the circuit.
a.2. seal wear: SLAVE and/or MASTER
b.1. oil leak from the filling valves
Metallic noise a. BUSHING a.1. bushing wear
Raising intermittently a. PINS a.1. pins demage