S e c t i o n Ill. OPERATION UNDER UNUSUAL CONDITIONS

TM 11-6625 -537-14-1

Table 3-3, Measurement of High Resistance

To obtain ualue of resistance in megohms

Range of unknown resistance

NULL setting

1 to 500 megohms

Subtract 10.00 from setting of voltage readout dials.

500 to 5,000 megohms

Subtract 1.00 from setting of voltage readout dials and multiply result

by 10.

Multiply setting of voltage readout dials by 100.

5,000 to 50,000 megohms

S e c t i o n Ill. OPERATION UNDER UNUSUAL CONDITIONS

equipment may be installed in tents, huts, or,

3-8. Operation in Arctic Climates

where necessary, underground dugouts. When

Subzero temperatures and climatic conditions

equipment is installed below ground, and when it

associated with cold weather affect the efficient

is set up in swamp areas, moisture conditions are

operation of electronic equipment. Instructions

more acute than normal in the tropics, Ventilation

and precautions for operation under such adverse

u s u a l l y is very poor, a n d the high relative

conditions follow.

humidity causes condensation of moisture on the

a. Handle equipment carefully.

e q u i p m e n t whenever the temperature of the

b. Keep equipment warm and dry. If electronic

equipment becomes lower than the ambient air.

v o l t m e t e r is not kept in a heated inclosure,

To minimize this condition, place lighted electric

construct an insulated box for the equipment.

bulbs under the equipment,

c. Make certain the equipment is warmedup

sufficiently before attempting to use it. This may

3-10. Operation in Desert Climates

take 10 to 15 minutes, depending on the tem-

The main problem with equipment operation in

perature of the surrounding air.

desert areas is the large amount of sand and dust

d. When equipment which has been exposed to

that enters the moving parts of the equipment.

the cold is brought into a warm room, it will start

Therefore, cleaning and servicing intervals shall

to sweat and will continue to do so until it reaches

be shortened according to local conditions.

room temperature. When the electronic voltmeter

has reached room temperature, dry it thoroughly.

3-9. Operation in Tropical Climates

When operated in tropical climates, electronic

3-10