The 'person responsible 'should be able to carry out simple fault-
finding procedures, including testing fuses and lamps removed from
equipment. Always switch-off before removing suspect fuses/lamps. A
multi-meter can then be used to determine whether the suspect fuse/
lamp is good/bad.
To test the fuse/lamp, use either the continuity connection on the
meter, or one of the omega (il) scales. Place the two probes together to
make sure that you have the meter set correctly. On a continuity setting,
the meter should buzz. On the omega scale, the meter will show zero reading
(digital) or full-scale deflection (moving needle). Place one probe at each
end of the suspect fuse - a good fuse will cause the meter to buzz (continuity
setting) or shown a zero/full-scale deflection reading (omega scale).
To test a lamp, one probe has to be on the earth contact and the
other on the positive (filament) contact. A good lamp will cause the meter
to buzz (continuity) or shown a zero/full-scale deflection reading (omega
scale). Blown fuses/lamps will not give any buzz. Readings on the omega
scale will remain the same as when the needles are kept apart and not
touching any other item.
Hand-held VHF radio batteries/GMDSS hand-held VHF
Some GMDSS hand-held VHF radios come with a five-year (or
similar) sealed lithium battery with an expiry date - just like an EPIRB
and SART battery. That type of battery should not be used with the
VHF radio for every day use, or your equipment will no longer meet
SO LAS requirements. If the battery is used for some emergency or other,
the date of first use should be recorded and a replacement obtained at
the first opportunity. A new, unused battery should supply your GMDSS
Hand-held VHF for up to eight hours.
Other hand-held VHF/UHF radios, supplied for onboard
communications, use rechargeable Nickel Cadmium (NiCad) batteries.
In some equipment, the hand-held set itself is kept in a charging unit
when not being used. With others, the individual batteries are removed
from the radio for charging. A typical rechargeable battery will supply
your hand-held radio for around six hours. Some types of battery can
suffer memory effect, which means that they must be fully discharged
before recharging - or they will 'forget' how much capacity they should
have. The effect of recharging before discharging is that you reduce the
time that the battery will supply your equipment. Manufacturers
instructions should be followed regarding use and charging of all portable
equipment batteries.
MARINE COMMUNICATIONS 199