Yokogawa DO402 Dissolved Oxygen Analyzer - Manual (Page 27)

IM 12J05D02-01E
Installation and wiring 3-7
3-3-3. AC power
Connect terminal 1 to the phase line of the AC power and terminal 2 to the zero line. The size of conduc-
tors should be at least 1.25 mm 2 . The overall cable diameter should be between 6 & 12 mm (0.24 & 0.47
in).
3-3-4. Grounding the housing
Protective grounding must be made to prevent electric shock.
To protect the instrument against interference, the housing should be connected to ground by a large
area conductor. This cable can be fixed to the rear of the housing using a braided wire cable. See figure
3-9. This is separated from input ground by a galvanic isolation.
Please be sure to connect protective grounding of
DO402G with cable of 1.25 mm 2 or larger cross
section in order to avoid the electrical shock to the
operators and maintenance engineers and prevent
the influence of external noise. And further connect
the grounding wire to the mark (100Ω or less).
3-3-5. Switching on the instrument
After all connections are made and checked, the
power can be switched on from the power sup-
ply. Make sure the LCD display comes on. All
segments will illuminate, then the instrument will
momentarily display its unique serial number. After
a brief interval, the display will change to the meas-
ured value. If errors are displayed or a valid meas-
ured value is not shown, consult the troubleshooting
section (Chapter 8) before calling Yokogawa.
Figure 3-9. Grounding the housing
DANGER
CAUTION
(M4 screw)