Kortek KT-2114DF, Руководство по обслуживанию

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1-1-2. Fire and Shock Hazard
Before returning the monitor to the user,perform the following safety checks:
1) Inspect each lead dress to make certain that the leads are not pinched or
that hardware is not lodged between the chassis and other metal parts
in the monitor.
2) Inspect all protective devices such as nonmetallic control knobs, insulating
materials, cabinet backs, adjustment and compartment cover or shields
isolation resistor-capacitor networks, mechanical insulations, etc.
3) To be sure that no shock hazard exists, check for leakage current in the
following manner.
a. Plug the AC line cord directly into a 120 or 230 Volt AC outlet.
(Do not use an isolation transformer for this test)
b. Using two clip leads, connect a 1.5K
Ω
, 10Watt resistor paralleled by a
0.15Uf capacitor in serial with an exposed metal chassis part and a
known earth ground, such as an electrical conductor and electrical
ground connected to a earth ground.
c. Use a SSVM or VOM with 1000 ohms per-volt or sensitivity to measure
the AC voltage drop across the resistor.
d. Connect the resistor to an exposed metal part having a return path to
the chassis(metal cabinet, screw heads, knobs, shafts, escutcheon,etc)
and measure the AC voltage drop across the resistor.
e. Any reading of 5.25 volt RMS(this corresponds to 3.5 milliampere AC)
or more is excessive and indicates a potential shock hazard. Correct
the shock hazard before returning the monitor to the user.
Figure 1-1. Leakage Current Test Circuit
LEAKAGE
CURRENT
TESTER
(READING SHOULD)
NOT BE ABOVE
0.5mA
TEST ALL
EXPOSED METAL
SURFACES
DEVI CE
UNDER
TEST
2-WIRE
CORD
ALSO TEST WITH
PLUG REVERSED
(USING AC ADAPTER
PLUG AS REQ UI RED)
Earth
ground