Sinclair PDM 35 Owner's Manual page 4

a displayed value
±
1999. When this is cx-
ceeded the display will show
=
ooo or ===ooo,
and the next highest range should be sclected.
Positive overload always gives fiashing bars. A
small negative overload will also give fiashing
bars (with negative symbol), but a larger one
will give fixed bars.
Remember, when switched to resistance the
display will show flashing overload until a
resistor lower than the maximum reading of
the range is connected. Should fixed bars
appear on the resistance function, connecting a
resistor will restore normal operation - this is
not a fault condition.
To avoid damage:
A. Never connect more than 1000 volts to
the DCV
=
socket, or more than
soo
volts R.M.S. to the ACV
Vl
socket.
B. Never connect a voltage source directly
to the mA -
n
socket.
C. Never connect an input greater than the
maximum permissible overload (see the
specification).
Selecting a Power Source
The meter operates from a standard 9-volt
battery. If possible a high power or Alkaline
type should be used - ask your dealer if in
doubt.
To obtain long battery life the meter must be
switched off whenever measurements are not
beingmade.
The condition of the battery may be checked
as follows: Select x 10VDC =and connect
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the red test lead to the DCV socket. Remove
the battery cover, switch the instrument on
and touch the test lead onto the negative
battery terminal. With a new battery the
reading should be about - 3 volts; if it is close
to zero or is positive the battery should be
replaced.
CAUTION - Never leave a weak or dead
battery in the instrument. Even 'leakproof'
types can leak chemicals that may cause
permanent damage to the instrument - this
will void the guarantee.
When continuous operation is required the
meter can be operated from AC power via an
optional AC adaptor. Plugging this into the
socket on the back automatically disconnects
the internai battery and increases the display
brightness.
For safety reasons only an approved adaptor
may be used; use of any other will void the
guarantee. In sorne countries the correct
Sinclair adaptor may not be available in which
case the dealer will supply an alternative
approved unit.
Sat"ety Precaution
This instrument has been designed to the
highest safety standards, but safe operation
depends on the user so we recommend the
following rules.
1.
Never connect a voltage to the instrument
which causes the common terminal to be
raised more than 1000 volts DC or 700
volts AC RMS above earth ground.
2.
Never use anything but an approved AC
adaptor to power the instrument.
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