Customer Communication Module (CCM) for Diesel Engines Caterpillar

The following specifications for wire and for cable are given to lower drops in voltage over long runs of wire. The specifications will also help minimize EMI/RFI interference.

• Do not run the data link wiring in the same raceway with high power cables. This restriction includes generator leads and AC cables.

• The wires that are connected to +B and -B on the CCM must be at least 16 AWG.

• The maximum length of the RS-232C cable is 15 m (50 ft).

• The maximum length for the Cat Data Link and the +/-B wire is 455 m (1500 ft) when a CCM is present. This length includes runs of wire between any multiple engine configuration. The maximum length of wire is 30.5 m (100 ft) when a CCM is NOT present.

Note: In order to conform to the European Economic Community (EEC) 336 Directive, the RS-232 cable must be shielded.

No terminations or splices are allowed on the above wires except as shown in the connection diagrams. The cable that is connected to the (+/-) CAT Data Link must be a 16 AWG shielded twisted pair cable. Use 123-2376 Electrical Cable.

Refer to Special Instruction, SEHS9951, "Customer Communication Module and Programmable Relay Control Module Installed on 3500B Engines with Electronic Instrument Panel" for additional information on 3500B wiring.

Table 1

CAT DATA LINK CABLE SPECIFICATIONS, RESISTANCE AND CAPACITANCE
	Measured Parameter
	C to C (1)	C to S (2)	SCSR (3)
Nominal Capacitance per meter (foot)	75 pF (23 pF)	144 pF (44 pF)	-
Total Nominal Capacitance 455 m (1500 ft)	0.035 µF	0.066 µF	-
Nominal Resistance per meter (foot) at 20 °C (68 °F)	-	-	14.0 mOhms (4.27 mOhms)
Total Nominal Resistance 455 m (1500 ft) at 20 °C (68 °F)	-	-	6.41 mOhms

( 1 )	Conductor to Conductor
( 2 )	Conductor to Shield
( 3 )	Single Conductor Series Resistance (16 AWG, 19/29 stranding)