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SAFETY INFORMATION
1. Parts that have special safety characteristics are identified by the symbol ! On schematics or by
special notes on the parts list. Use only replacement parts that have critical characteristics
recommended by the manufacturer.
2. Make leakage current or resistance measurements to determine that exposed parts are acceptably
insulated from the supply circuit before returning the unit to the customer. Use the following checks to
perform these measurements:
A. Leakage Current Hot Check-With the unit completely re-assembled, plug the AC line cord directly
into a 240V AC outlet. (Do not use an isolation transformer during this test.) Use a leakage current
tester or a metering system. With the unit AC switch first in the ON position, then in the OFF position,
measure from a known earth ground (metal water pipe, conduit, etc.) to all exposed metal parts of the
unit ( handle bracket, metal cabinet, screw heads, metallic overlays, control shafts, etc.), especially any
exposed metal parts that offer an electrical return path to the chassis. Any current measured must not
exceed 0.5 mA. Reverse the unit power cord plug in the outlet and repeat test. ANY
MEASUREMENTS NOT WITHIN THE LIMITS SPECIFIED HEREIN INDICATE A POTENTIAL
SHOCK HAZARD THAT MUST BE ELIMINATED BEFORE RETURNING THE UNIT TO THE
CUSTOMER.
B. Insulation Resistance Test Cold Check-
(1) Un-plug the power supply and connect a jumper wire between the two prongs of the plug.
(2) Turn on the power switch of the unit.
(3) Measure the resistance with an ohmmeter between the jumpered AC plug and each exposed
metallic cabinet part on the unit. When the exposed metallic part has a return path to the chassis, the
reading should be between 1 and 5.2 Mega Ohms. When there is no return path to the chassis, the
reading must be “infinite”. If it is not within the limits specified, there is the possibility of a shock
hazard, and the unit must be repaired and re-checked before it is returned to the customer.
ELECTROSTATIC DISCHARGE SENSITIVE (ESDS) DEVICE HANDLING
We recommend the following precautions when repairing, replacing or transporting ESDS devices:
• Perform work at an electrically grounded work station.
• Wear wrist straps that connect to the station or heel straps that connect to conductive floor mats.
• Avoid touching the leads or contacts of ESDS devices or PC boards even if properly grounded. Handle
boards by the edges only.
• Transport or store ESDS devices in ESD protective bags, bins, or totes. Do not insert unprotected
devices into materials such as plastic, polystyrene foam, clear plastic bags, bubble wrap or plastic trays.
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