TM 5-6675-322-14
(2) Saturate wet bulb wick as follows:
(a) Remove air intake, turn psychrometer so wet bulb faces down, and
thoroughly saturate wet bulb wick.
NOTE
Be sure no water contacts the thermometer tubes or the dry bulb. Remove
any water spilled on the tubes or dry bulb.
( b ) R e p l a c e s l i d i n g a i r i n t a k e , a n d t u r n r i g h t s i d e u p .
( 3 ) O p e n s l i d i n g d o o r,
replace water bottle, and close sliding door.
NOTE
Whether placed on a bench or hand held, air intake and both exhaust ports
m u s t b e e n t i r e l y f r e e o f o b s t r u c t i o n.
The hand psychrometer samples air
to which it is exposed. Care must be taken to use it far enough away from
sources of heat, cold, or moisture.
Be sure hand does not contact ther-
mometers during use.
(4) Place hand psychrometer on flat surface or hold in hand with thermometer
g r a d u a t i o n s f a c i n g u p a n d a i r i n t a k e p o i n t i n g t o l e f t .
CAUTION
Be sure to turn motor off after each observation .
Unnecessary usage will
g r e a t l y s h o r t e n l i f e o f b a t t e r i e s .
(5) Turn on/off switch ON and allow wet bulb temperature to stabilize.
(6)
If
thermometer
illumination
is
desired,
turn
knob
fully
right.
NOTE
I f w e t b u l b t e m p e r a t u r e f a i l s t o s t a b i l i z e w i t h i n 2 . 5 m i n u t e s a f t e r b e i ng
energized, fan motor is probably running too slow due to weak batteries.
(7) Turn on/off switch OFF.
(8) Record wet and dry bulb temperatures.
( 9 ) R e a d p s y c h o m e t r i c s l i d e r u l e a s f o l l o w s:
(a) Aline wet bulb temperature and dry bulb temperature on slide rule.
9-44
