jcb ROBOT 150, Service Manual

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How to Measure Voltage (VOLTS)
On the AVO 2003
Move the right slider switch to position
A
, and the left hand slider to the appropriate range.
On an analogue meter
Turn the dial to the appropriate DC Volts range.
Connect the black probe to the nearest available suitable earth point, usually this will be either the battery negative, or the
chassis. Connect the red probe to the wire or contact from which you are measuring the voltage.
How to Measure Resistance (OHMS)
Make sure there is no power to the part of the circuit you are about to measure.
Connect one probe at one end of the component or wire to be checked and the other probe at the other end. It does not matter
which way round the two probes are placed.
On the AVO 2003
Move the right hand slider switch to position
B
, and the left hand slider switch to the appropriate Ohms (û) range.
On an analogue meter
Move the dial to the appropriate Ohms (û) range.
How to Measure Continuity
Make sure there is no power to the part of the circuit you are checking for continuity.
Connect one probe to one end of the component or wire to be checked and the other probe to the other end. It does not matter
which way round the two probes are placed.
On the AVO 2003
Move the right hand slider switch to position
B , and the left hand slider switch to position C .
If there is continuity (i.e. very low resistance) between two points the needle will move across fully (or almost fully) to the right
hand side of the scale.
How to Test a Diode or a Diode Wire
A diode wire is a diode with male and female connectors soldered onto each end, with the diode sealed in heatshrink.
On the AVO2003:
Move the right hand slider to position
A , and the left hand slider switch to position C .
Connect the black probe to the end of the diode marked with a band, or to the male connector of the diode wire, the red probe
should be connected to the other end of the diode or diode wire. If the Avometer does not buzz the diode is faulty.
Connect the red probe to the end of the diode marked with a band, or to the male connector of the diode wire, the black probe
should be connected to the other end of the diode wire. If the Avometer does not read "1" the diode is faulty.
On an analogue meter:
Select the Ohms 1000s (1k) range.
Connect the black probe to the end of the diode marked with a band, or to the male connector of the diode wire, the red probe
should be connected to the other end of the diode or diode wire. The meter should read 20-400 Kû, if it reads more than this the
diode is faulty.
Select the Ohms 100s range.
Connect the red probe to the end of the diode marked with a band, or to the male connector of the diode wire, the black probe
should be connected to the other end of the diode or diode wire. The meter should read 300-400û, if it reads less than this the
diode is faulty.
Section C
Electrics
9803/8500
Section C
2 - 2
Issue 1
Test Methods