Rockwell Automation SB3000 High Pwr SB3000 AC Pwr Modules (RCS) - Manual (Page 36)

4-2 SB3000 Power Modules (RCS)
4.2 Power Module Tests with Input Power Off
Use the following procedure to perform the SB3000 Power Module tests:
Step 1. Turn off and lock out AC input power.
Step 2. Wait ten minutes to allow the DC bus voltage to dissipate.
Step 3. Open the cabinet doors and check the voltage across the DC bus bars,
347 A,B,C (+ bus) and 345 A,B,C (- bus), with an external voltmeter to ensure
the DC bus capacitors are discharged before touching any internal
components. See figure 4.1.
Step 4. Check the AC input and DC bus output fuses.
Step 5. If a fuse is blown, use a multimeter to check the DC bus, bus capacitors, AC
input terminals, and the input IGBTs. See tables 4.1 and 4.2.
Step 6. If a capacitor is defective, replace the capacitor bank assembly as described
in section 4.4.4. If an IGBT is defective, refer to section 4.4.2.
!
ATTENTION: The Power Module is not isolated from earth ground. AC
line powered test instruments used to measure Power Module signals
must be isolated from ground through an isolation transformer. This is
not necessary for battery-powered test instruments. Failure to observe
this precaution could result in bodily injury.
ATTENTION: If a megohmmeter (megger) is used to verify an
inadvertent ground internal to the motor, make certain that all leads are
disconnected between the rotating equipment and the Power Module
cabinet. This will prevent damage to electronic circuitry (Power Modules
and their associated circuitry) due to the high voltage generated by the
megger. Failure to observe this precaution could result in damage to or
destruction of the equipment.
!
ATTENTION: DC bus capacitors retain hazardous voltages after input
power has been disconnected. After disconnecting input power, wait ten
(10) minutes for the DC bus capacitors to discharge. Open the cabinet
doors and check the voltage across the DC bus bars, 347 A,B,C (+ bus)
and 345 A,B,C (- bus), with an external voltmeter to ensure the DC bus
capacitors are discharged before touching any internal components.
Failure to observe this precaution could result in severe bodily injury or
loss of life.