Du Pont SORVALL RC-5 Service Manual page 132

Warning:
Before the centrifuge is serviced,
ensure that the centrifuge and wall
receptacle are checked for ground
continuity. Failure to do so can
result in a serious electrical shock.
P/N: 50589-3
INSTRUCTIONS
RC-5B / RC-5C Preventative Maintenance Kit
(Kit Catalog No. 12010)
Pre-run checks:
Centrifuge and wall outlet continuity check:
Check that the ground lug of the electrical plug is properly grounded and
is shorted to the frame of the centrifuge. Check that the ground "lug of
the outlet (wall receptacle) is properly grounded.
1. Set the main circuit breaker, POWER switch, to OFF.
2. Disconnect the power cord from the power supply.
3. Check centrifuge ground continuity as follows:
a. Set a DVM to the lowest resistance scale.
b. Attach one probe of the DVM to ground lug on the power cord.
c. Touch the other probe of the DVM to the chassis of the centrifuge.
The meter should show less than 0.1 ohms.
4. Check wall outlet ground continuity as follows:
a. Set the DVM to volts ac scale.
b. Measure each side of the line to the ground receptacle. The voltage
should be "115 Vac. If no voltage is measured, the receptacle is not
properly grounded.
c. Measure the voltage from line to line. The voltage should match
the voltage found on the centrifuge name plate (208 to 230 vac).
5. Remove the DVM and probes.
Door latch microswitch check:
1. Connect the centrifuge power cord to the mains supply.
2. Set the main circuit breaker, POWER switch, to ON.
3. Open the centrifgue door by depressing the "DOOR" button on the
front control console (RC-5B) or under the right front of the centrifuge
deck (RC-5C). The door should open to approximately 45°.
for the
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