3406 INDUSTRIAL & MARINE ENGINES Caterpillar

Output to input ratio ... 2 to 1

Range ... 0 to 2500 rpm

Check at full load engine rpm.

Maximum adjustment ... ± 7.5%

Maximum external circuit resistance ... 20 ohms

Maximum operation temperature ... 180° F (82° C)

Maximum of two tachometers to be operated from one sending unit.

(1) Adjustment screw.

(2) Cap.

(3) Rubber washer.

3N7983 (24V) or 3N8160 (32V); Use with 3N7477 Pick-up

Range ... 0 to 500 rpm

Check at ... 375 rpm

Maximum adjustment ... ± 3%

Maximum length of wire between tachometer and pick-up ... 100 ft.(30 m)

Maximum of two tachometers to be operated from one pick-up.

(1) Clearance between pick-up and gear teeth ... .022 to .033 in.(0.56 to 0.84 mm)

(2) Pick-up.