Hammond 340107 Service Manual page 2

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SAFETY NOTICE
Great care has been taken in the design and manufacture of this product to assure that no
shock hazard exists on any exposed metal parts. Internal service operations can expose the
technician to hazardous line voltages and accidentally cause these voltages to appear on
exposed metal parts during repair or reassembly of product components. To prevent this, work
on these products should only be performed by those who are thoroughly familiar with the
precautions necessary when working on this type of equipment.
To protect the u.er, It I. required that all enclo.ure part. and .afety Interlock. be re.tored to
their original condition and the following te.t. be performed before returning the product to
the owner after any .ervlce operation.
Plug the AC line cord directly into a line voltage AC receptacle (do not use an Isolation
transformer for this test) and turn the product on. Connect the network (as shown below) In
series with all exposed metal parts and a known earth ground such as a water pipe or conduit.
Use an AC VOM of 5,000 ohms per volt or higher sensitivity to measure the voltage drop across ..-.
the network. Move the network connection to each exposed metal part (metal chassis, screw
heads, knobs and control shafts, escutcheon, etc.) and measure the voltage drop across the
network. Reverse the line plug and repeat the measurements. Any reading of 4 volts RMS or
more is excessive and Indicates a potential shock hazard which must be corrected before
returning the product to the user.
YOM
AC SCALE
10K
2W
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I
I
II
.01 MF
CERAtIl C RF
BYPASS CAP
TEST CLI PS
CONNECTED TO IINOWN
EARTH GROUND
-
TO EXPOSEO METAL PARTS
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