Home Repair Manuals Hotpoint WMA32 Dismantle & Repair
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1.2.1
How to use your Meter
This is the only piece of equipment we will give instructions on how to use, mainly
because if you have never had to use one before you may not be aware of the different
settings and how they work.
There are three settings
OHMS depicted by this symbol
Ω
MegOHMS depicted by this symbol M
Ω
kilOHMS depicted by this symbol k
Ω
The two main ones you will use are Ohms and MegOhms, and they are used when testing
for continuity in the wiring or for resistance in components electronics.
Ohms: Should you need to know if there is a break in a circuit or wire, connect one of
the meter leads to one end of the circuit/cable to be tested and the other lead to the other
end. The meter reading should be 0.5
Ω
or lower. If the needle goes right across the dial
this would indicate a break in the circuit. This test is called a continuity test and is used to
check for defective connections, cables, circuits etc.
MegOhms: This tests if there is a breakdown in the wiring insulation anywhere in the
system.
Set your meter to MegOhms M
Ω
and connect one of the leads to an earth, this can be the
plug or the cabinet or any point that is earthed on the machine. Connect the other meter
lead to either the live terminal on the component to be tested or the neutral. The meter
reading should be above 2 M
Ω
. If it is lower than this i.e. the needle goes right across the
dial or even halfway across there is an earth leakage. This is not classed as a dead short,
where the fuse in the plug would blow and neither is it enough to give you a fatal electric
shock, but will trip some milliamp fuse boxes and possibly interfere with the smooth
running of your machine. This is called an insulation test, and one of the most common
positive readings come from the motor, where carbon from the brushes builds up inside
the motor housing and forms a bridge between the casing and the wiring, which then trips
the milliamp fuse box. This is easily rectified by cleaning out the motor housing, but
earth leakage between cables can be harder to locate. Check anywhere they may rub such
as the cabinet or balance weights, sharp edges or corners.
Do not do this test on the module or you will damage some of the circuits within it.
