BRIDGE RECTIFIER TEST Caterpillar

BRIDGE RECTIFIER TEST

Usage:

ENGINES

GENERATOR SETS

POWER SYSTEMS

ARTICULATED TRUCKS

3116 (4PG,2MR),
3126 (BEJ,DCS),
3176 (3NL,2AW),
3196 (1DW),
3304 (02B,04B,10E,83Z,9HK),
3306 (09A,66D,70R,23C,64Z,7JB,85Z,8JJ,9NR,5GZ,1BM),
3406 (90U,91U,92U,75Z,6TB,2WB,4TB,4MG,5KJ,7FB,3ZJ,5EK,6TS,8PN,6BR,9NN,3ER,1LS,4ZR,2WS,5DS,1LW,1MM),
3408 (67U,99U,28V,78Z,9ER,7PR),
3412 (38S,60M,81Z,2WJ,8AR,4CR,BAX,BAK),
3456 (3LW,BGA,EPE),
3508 (6PN),
3512 (24Z),
C-9 (CLJ),
C-10 (BCX),
C-12 (BDL),
C-15 (6NZ,BEM),
C-16 (7CZ,BFM) ENGINES;
3304 ENGINE (DED),
3306 ENGINE (8NS,EFA),
3406 ENGINE (9ES,8AZ),
3412 (4BZ,9EP,BCW),
3456 ENGINE (CAH,CBX,CCB,GHJ),
3508 ENGINE (5KW,5PW,CNB,CNF,BGX,CAW),
3512 ENGINE (6GW,6WW,CMC,CMJ,BLF,BRK,FDR,FDE),
3516 ENGINE (8NW,8TW,FDN,CMD,BMB,BPJ,CAL,CDA,FDX) GENERATOR SETS;
PM3412 (5FL) POWER SYSTEMS;
D25 (9YC),
D30 (05A,7ZC),
D35 (2GD,3FD),
D300 (4SD),
D350 (8XC),
D400 (1MD) ARTICULATED TRUCKS

Problem:

Potential failure of 7N-7122 Rectifier Assembly on the 5N-5692 Alternator Group.

Solution:

The Bridge Rectifier Test identifies the potential failure of the 7N-7122 Rectifier Assembly which is used on 20SI Series Alternators (5N-5692 Alternator Group). Failures of the 7N-7122 Rectifier Assembly can be repaired rather than replacing the 5N-5692 Alternator. The replacement part for the 7N-7122 Rectifier Assembly is the 206-4202 Rectifier Assembly.

Bridge Rectifier Test

1.Visual inspection. Look to see if there is visible damage present on 7N-7122 Rectifier Assembly. If the rectifier has failed, replace the rectifier. If the rectifier is good, proceed to Step 2.

2.Perform a positive diode check and a negative diode check. Refer to Service Manual, SENR4978, "Delco Remy 20-SI Series Alternator. If the rectifier has failed, replace the rectifier. If the rectifier is good, proceed to Step 3.

3.Remove the 7N-7122 Rectifier Assembly. Visually inspect for damaged diode clips or failed diode clips. Attempt to move the diode clips. If a diode clip moves freely, the rectifier has failed. If the rectifier has failed, replace the rectifier.

If the 7N-7122 Rectifier Assembly completely passes the Bridge Rectifier Test, resume alternator troubleshooting. Refer to Service Manual, SENR4978, "Delco Remy 20-SI Series Alternator".