Sirona orthophos xg 3, Руководство по установке

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6 Safety checks Sirona Dental Systems GmbH
6.1 Checking the protective ground wires Installation Instructions ORTHOPHOS XG 3
60 51 416 D 3352
60
D 3352.031.03.18.02
DANGER
Shock hazard! It is essential that you switch the X-ray
unit OFF before replacing any components!
If you have not done it already...
Switch OFF the line voltage at the main switch of the
building installation.
Disconnect the power cable and the second protective
ground wire from the building installation.
Remove the following cover parts:
– Profile cover
– Tube assembly cover, front
– Tube assembly cover, rear
Check whether the ground wire resistance complies
with the specifications
A power source with a current of at least 0.2 A and a
no-load voltage of 24 V max. and 4 V min. is required.
Connect the power source between the measuring
points specified in the table for at least 5 s and mea
-
sure:
– the voltage drop with the voltmeter
– the current with the ammeter and
– calculate the resistance using the formula R = U / I
6.1 Checking the protective ground wires
V
A
~
A
B
C
D
E
Ammeter
Power source
Measuring point
Central ground wire
Measuring points B-E
Voltmeter
Measuring setup for protective
ground wire test
Protective ground wire test
between...
A and
B GNYE wire 0,1
Ω
A and
C 2. Protective
ground wire 0,1
Ω
A and
D Housing DX32 0,2
Ω
A and
E Tube assembly
housing 0,2
Ω