Omron NT31 NT31C manual Points Inspected, Point Inspection Details Criterion Inspected Instrument

Inspection and Cleaning Section 7-4

•100% cotton cloth

•Hygrometer (required in some cases)

•Thermometer (required in some cases)

•Synchroscope (required in some cases)

•Pen-writing oscilloscope (required in some cases)

Points Inspected

Inspect the following points to determine if there is any divergence from the stated criteria. If there is, either improve the surrounding environment so that the values fall within the stated range, or adjust the NT31/NT31C, for example by re-tightening screws.

Point	Inspection Details	Criterion	Inspection
Inspected			Instrument
Power supply	Fluctuation in power supply terminal	Permissible voltage fluctuation range	Tester
voltage	voltage	(24 VDC −15% to +10%)
Ambient	Ambient temperature (temperature in the	0 to 50_C	Thermometer
environmental	operation panel)
conditions
	Ambient humidity (humidity in the	35% to 85% RH	Hygrometer
	operation panel)
	Presence/absence of dust	Dust must not be settled	Visual inspection
Mounting	Looseness of mounting brackets, etc.	To be no looseness	Philips screwdriver
conditions
	Connector connections of connecting	To be fully inserted and locked, with	Philips screwdriver
	cable	no looseness
	Looseness of screws in external wiring	To be no looseness	Philips screwdriver
	Conditions of external connecting cables	Faults such as incipient disconnection	Visual inspection
Components	Brightness of the backlight	Must be sufficiently bright.	Visual inspection
with limited		Backlight life:
lives
		Brightness is halved after about
		25,000 hours in use at medium
		brightness, or about 10,000 hours in
		use at high brightness.

Note 1. Do not disassemble for repairs or modification.

2.The disposal of the unit (including batteries to be disposed and backlight) may be regulated by national or local authorities. Dispose of them in accor- dance with the laws and regulations of the relevant country and local author- ity.

Reference: Desire on replacing the NT31/NT31C

When replacing the NT31/NT31C after discovering a fault during inspections, note the following points:

SBe sure to switch the power OFF before starting replacement.

SAfter replacement, check that the new NT31/NT31C is not subject to the same error.

SIf a faulty unit is returned for repairs, write as detailed a description of the fault as possible and send this description together with the unit to the OMRON ad- dress indicated on the back cover of this book.

246