Hologic DISCOVERY A, Technical Manual

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Discovery QDR Series Technical Manual
3-23
17. Attach the Communications Cable to JP10 on the Distribution Board and the
ground strap to the grounding stud.
18. Attach the other end of the Communications Cable to the PCI Communications
Controller Board connector at the rear of the PC.
19. Plug the Operator Console AC Supply Cable to the Power Strip male connector.
3.3.2 Check Power Line Voltage
Hologic specifies that the Discovery be powered from a dedicated power line.
3.3.2.1 Measure Line Voltage
Before plugging in the Discovery, measure the voltage (neutral to phase) with an AC
voltmeter at the outlet from which the unit will draw power. The measured voltage must
be within
±
10% of the voltage shown on the power label (located where the power cord
attaches to the Torroid Power Module). The Discovery Torroid Assembly is a step up/step
down isolation transformer, which can be re-strapped to accommodate other input
voltages. See Figure 3-21 for the most common configurations of the isolation
transformer.
There are two standards for conductor color-coding. The North American standard
specifies the BLACK conductor as LINE and the WHITE as NEUTRAL, while the
International standard defines the BROWN conductor as LINE and the BLUE as
NEUTRAL.
Note: Be sure to change the label if you re-strap the transformer.
SAFETY PRECAUTIONS
There are a number of safety precautions that MUST be observed when servicing the
Discovery systems.
HIGH VOLTAGE: Voltage levels that can injure or be fatal are present through the
Discovery systems. The line voltage (100, 120, 230 volts) is supplied to the Torroid
Assembly and the scanner. The X-ray source unit contains 140kV as well as other AC
and DC voltages. The pedestal motors use 230 volts regardless of the line voltage. Use
caution when checking, calibrating, and troubleshooting. Always trip the main breaker
when replacing components.
X-RADIATION: Service personnel are required to wear a dosimeter. Do not leave the
system unattended in X-RAY SURVEY (SURVEY mode).
ESD PRECAUTIONS: To prevent damage due to ESD (Electrostatic Discharge), you
must take precautions when handling components. Remove any charge from your body
by wearing an approved and properly grounded wrist strap. Keep PCBs in their ESD
protective bag until you are ready to install them. Treat defective PCBs as new to
prevent any additional damage.
Power Requirements for all
Discovery models: 100VAC 16A 50/60Hz, Max apparent resistance = 0.32 ohm
120VAC 14A 50/60Hz, Max apparent resistance = 0.32 ohm
230VAC 8A 50/60Hz, Max apparent resistance = 1.28 ohm