CCDA Test Circuit Check (CRC)

TM 55-4920-430-13

4-66. CCDA Test Circuit Check (CRC). (See fig. 4-9.) The CCDA discrete signal outputs are simu-

lated by three toggle switches, the BRAKE, CLUTCH, and CMD. The switches apply a voltage or open

circuit connection. The clutch and brake are interconnected so that a clutch 1 voltage level requires a 1

voltage level at the brake discrete output. Proceed as follows:

a. Set switch to position indicated below.

b. Connect ac signal voltage and digital multimeter to the receptacle pins listed below.

NOTE

Receptacle J6 is marked CCDA.

DIGITAL

VOLTAGE

MULTIMETER/

MEASUREMENT

CONTROL/SWITCH

STEP

TEST PROCEDURES

NORMAL RESULTS

NOMENCLATURE

POSITION

NO.

112.5 to 117.5Vac

AFCS 115VAC

(1)

CCDA J6-B (line)

400Hz POWER

to J6-C

Switch S2

NOTE

CCDA Cable W6 has a jumper from J6-C to J6-V

to connect the 28Vdc and 115Vac grounds to-

gether for CCDA tests. Connect a jumper be-

tween receptacle pins J6-C and J6-V.

24 to 28.5Vdc

(2)

AFCS 28VDC

CCDA J6-A to J6-C

POWER switch S3

Apply 13Vac to

(3)

None

CCDA J6-F (line)

to J6-C

(4)

CCDA DISCRETE SIGNAL switches

(a) 1

(a) J6-G(+) to J6-C

(a) 24 to 28.5Vdc

(a) BRAKE switch

S39

(b) OPEN

(b) 0

(b) J6-G(+) to J6-C

(b) BRAKE switch

S39

S40 (For Brake 1)

(d) OPEN

(d) J6-H(+) to J6-C

(d) CLUTCH switch (d) 0

S40 (For Brake 1)

(e) OPEN

(e) J6-H(+) to J6-C

(e) CLUTCH switch (e) 1

S40 (For Brake 0)

(f) OPEN

(f) CLUTCH switch (f) 0

(f) J6-H(+) to J6-C

S40 (For Brake 0)

4-74