Simpson 260-6LPM, Instruction Manual

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4.1 Safety Precautions
The 260 is intended for use only by personnel qualified to recognize shock haz-
ards and trained in the safety precautions required to avoid possible injury.
a. Do not work alone when making measurements of circuits where a shock
hazard might exist. Notify a nearby person that you are making, or intend to
make, such measurements.
b. Locate all voltage sources and accessible current paths before making mea-
surement connections. Be sure that the equipment is properly grounded and
the right rating and type of fuse is installed. Set the Instrument to the proper
range before applying power. Voltage might appear unexpectedly in defec-
tive equipment. An open bleeder resistor can result in a capacitor retaining a
dangerous charge. Turn the power off and discharge all capacitors before
connecting or disconnecting the Instrument.
c. Inspect the test leads for cracks, breaks or crazes in the insulation, probes
and connectors before each use. If any defects are noted, replace the test
leads immediately.
d. Do not make measurements in a circuit where corona is present. Corona can
be identified by a pale blue color emanating from sharp metal points in the
circuit, or by a buzzing sound, or by the odor of ozone. In rare instances, such
as around germicidal lamps, ozone might be generated as a normal function.
Ordinarily, the presence of ozone indicates the presence of high voltage and
a probable electrical malfunction.
e. Hands, shoes, floor and workbench must be dry. Avoid making measure-
ments under humid, damp or other environmental conditions that could affect
the dielectric withstanding voltage of the test leads or the Instrument.
f. For maximum safety, do not touch test leads or Instrument while power is
applied to the circuit under test.
g. Use extreme caution when making measurements where a dangerous com-
bination of voltages could be present, such as in an RF amplifier.
h. Do not make measurements using test leads of lesser safety than those origi-
nally furnished with the Instrument.
i. Do not touch any object which could provide a current path to the common
side of the circuit under test or power line ground. Always stand on a dry
insulated surface capable of withstanding the voltage being measured.
4.2 Movement Overload Protection
In addition to the overload sensing circuit and fuse, a varistor gives additional
protection to the indicating instrument movement. The varistor limits the current
through the moving coil in the event of extreme overload and transients. However,
no overload protection system is completely foolproof and misapplication on high
voltage circuits can damage the Instrument. Always exercise care and caution to
protect both yourself and the Instrument.
4.3 Adjust Pointer for Zero
With the Instrument in the operating position, check the pointer for zero indication
at the left end of the scale when there is no input. If pointer is off zero, adjust the