B&K Precision 2640 - Manual - Manual (Page 5)

5
 DC Power
The operating Personnel must use the DC adaptor supplied with this instrument. Other
adaptors could result in damage to this instrument and it is the limitation of warranty Exterior
DC input connector should be matched with polar. DC connector tip must attach with (+) polar
grounding.
The operating personnel must use grounded power Restore this instrument
 Instrument care
＊Avoid direct light
＊Keep away the heating system
＊Avoid high temperature (Ex. Inside of the car during the summer time)
＊Keep away from liquids
＊Avoid high moisture and/or poor ventilation
＊Keep away from dust and/or smoke
＊Avoid extremely low temperature