Yokogawa DO402 Dissolved Oxygen Analyzer - Manual (Page 76)

IM 12J05D02-01E
7-2 maintenance
7-2. Periodic maintenance for the EXA DO402G converter
The DO402G converter requires very little periodic maintenance. The housing is sealed to IP65 (NEMA
4X) standards, and remains closed in normal operation. Users are required only to make sure the front
window is kept clean in order to permit a clear view of the display and allow proper operation of the
pushbuttons. If the window becomes soiled, clean it using a soft damp cloth or soft tissue. To deal with
more stubborn stains, a neutral detergent may be used.
NOTE:
Never used harsh chemicals or solvents. In the event that the window becomes heavily stained or
scratched, refer to the parts list (Chapter 9) for replacement part numbers.
When you must open the front cover and/or glands, make sure that the seals are clean and correctly fit-
ted when the unit is reassembled in order to maintain the housing’s weatherproof integrity against water
and water vapor. The DO measurement uses small signal currents and may otherwise be prone to prob-
lems caused by exposure of the circuitry to condensation.
7-3. Fuse Replacement
This section describes how to replace the power supply fuse.
• Use only a fuse of the specified current, voltage and type ratings to prevent fire.
• Power to the instrument must be turned off at the external breaker before replacing the fuse. After
replacing the fuse, install a high-voltage shield plate before turning the power on.
• Do not short circuit the fuse holder.
Specified Ratings of the Power Supply Fuse
The power supply fuse (recommended fuse) used in the DO402G is as follows.
• 100/115 V AC version
Maximum rated voltage: 250 V
Maximum rated current: 200 mA
Compliance: UL, CSA, VDE, Japan’s Electrical Appliance and material Safety Law
Part number: A1105EF
• 230 V AC version
Maximum rated voltage: 250 V
Maximum rated current: 100 mA
Compliance: UL, CSA, VDE, Japan’s Electrical Appliance and material Safety Law
Part number: A1103EF
DANGER