Wells-Gardner D9300 Series Benutzerhandbuch
Wells-Gardner Electronics Corporation
1
1. SAFETY
PRECAUTION:
WARNING: Service should not be attempted by anyone unfamiliar with the necessary
precautions on this unit. The following precautions are necessary during servicing.
1-1
Some parts, such as a picture tube in this unit, have special safety-related characteristics
for X-RAY RADIATION protection.
For continued safety, the parts replacement should be undertaken referring to below
article (1-2 and 1-5).
for X-RAY RADIATION protection.
For continued safety, the parts replacement should be undertaken referring to below
article (1-2 and 1-5).
1-2
Many electrical mechanical parts in this unit have special safety-related characteristics for
protection against shock hazard and others. These characteristics are often passed
unnoticed by visual inspection and the protection afforded by them cannot necessarily be
obtained by using replacement components rated for higher voltage, wattage, etc.
Replacement parts which have these special characteristics are identified in the manual
and supplements by shading on the schematic diagram and the parts list. Before replacing
any of these components, read the parts list in this manual carefully.
protection against shock hazard and others. These characteristics are often passed
unnoticed by visual inspection and the protection afforded by them cannot necessarily be
obtained by using replacement components rated for higher voltage, wattage, etc.
Replacement parts which have these special characteristics are identified in the manual
and supplements by shading on the schematic diagram and the parts list. Before replacing
any of these components, read the parts list in this manual carefully.
1-3
When replacing the chassis in the cabinet, always be certain that all the protective devices
are installed properly, such as insulating covers, strain relief, etc.
are installed properly, such as insulating covers, strain relief, etc.
1-4
Before replacing the back cover of the set, thoroughly inspect the inside of the cabinet to
see that no stray parts or tools have been left inside.
see that no stray parts or tools have been left inside.
1-5
Before returning the set to the customer, always perform an AC leakage current check on
the exposed metallic parts of the cabinet, such as terminal, screwheads, metal overlays,
control shafts, etc. To insure the set is safe to operate without danger of electrical shock,
plug the AC line cord directly into a 120V AC outlet (do not use a line isolation
transformer during this check). Use an AC voltmeter having 5000 ohms per volt or more
sensitivity in the following manner. Connect a 1500 ohm, 10 watt resistor, parallel with a
(0.15uF) capacitor. Reverse the AC plug in the AC outlet and repeat the AC voltage
measurements for each exposed metallic part. Voltage measured must not exceed 0.3V
RMS. This corresponds to 0.2mA AC, any value exceeding this limit constitutes a potential
shock hazard and must be corrected immediately.
the exposed metallic parts of the cabinet, such as terminal, screwheads, metal overlays,
control shafts, etc. To insure the set is safe to operate without danger of electrical shock,
plug the AC line cord directly into a 120V AC outlet (do not use a line isolation
transformer during this check). Use an AC voltmeter having 5000 ohms per volt or more
sensitivity in the following manner. Connect a 1500 ohm, 10 watt resistor, parallel with a
(0.15uF) capacitor. Reverse the AC plug in the AC outlet and repeat the AC voltage
measurements for each exposed metallic part. Voltage measured must not exceed 0.3V
RMS. This corresponds to 0.2mA AC, any value exceeding this limit constitutes a potential
shock hazard and must be corrected immediately.