7 - Fault Finding
1. 3
Sensors
Flow Sensor Inspection
The flow sensor is a “Proximity” type sensor and may be tested for
correct operation as follows:
•
Switch on the power to the sprayer but do not run the pump
(ie 0 bar).
•
Locate the Flow sensor in the fluid supply manifold at the
front of the sprayer and loosen it’s threaded retaining nut.
•
Rotate the spindle by hand (do not use compressed air) and
watch the in-built LED test light for a signal.
If the sensor is working correctly the red LED will pulse with each
revolution of the spindle. If the Flow sensor is found to be
functional, re-install it in the manifold taking care not to damage
the “O” ring seal (use rubber grease on re-assembly).
Fluid system
Fault
Possible cause
Suggested action
Pressure increasing.
Boom nozzle filters becoming blocked
Clean all filters.
Formation of foam.
Air is being sucked into system.
Check tightness/gaskets/O-rings of all fittings on
suction side.
Excessive liquid agitation.
Reduce agitation
Make sure that returns inside tank are present.
Use foam damping additive.
Liquid leaks from the bottom of HARDI pump.
Damaged diaphragm
Replace. See “Maintenance” section of this
manual for instructions on servicing pumps
Operating unit not functioning.
Blown fuse(s).
Check mechanical function of micro-switches. 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. (-).
Section valves not closing properly.
Check valve seals for obstruction and wear,
overhaul if necessary (see “Maintenance” section
of this manual for details). Check micro-switch
plate position. Loosen screws holding plate a 1/2
turn. Check that the micro-switches in the EFC
valve motors are shutting the motors off correctly
No power.
Wrong polarity. Check that brown is pos. (+), Blue
is neg. (-).
Check printed circuit board for dry solders or
loose connections.
Check fuses and holders for integrity and security.
Summary of Contents for Mercury Covamax series
Page 1: ...MERCURY COVAMAX Operator Instruction Manual 67002404 100 HAU 08 2009 www hardi com au...
Page 10: ...Table of Contents TOC 8...
Page 18: ...2 Safety 2 6...
Page 88: ...6 Maintenance 1 18 Maintenance Activity Record Date Service Performed...
Page 92: ...7 Fault Finding 1 4...
Page 100: ...8 Technical Specifications 8 8...
