A-B 1746-HCA Module MOT Module Cable Communication Test

SLC 500 Fast Analog  I/O Module

Install and Wire the Modules

This chapter describes procedures to install fast analog I/O modules in an SLC 500 system. The procedures include the following tasks.

• determine the module’s power requirements

• determine compatibility with other I/O modules

• configure input channels

• select the I/O rack slot

• install the module

• consider when wiring

– using system wiring guidelines

– grounding the cable

– determining cable length

• minimize electrical noise interference

• wire the module

• minimize ground loops

• label the terminal block

Select the I/O Rack Slot Two factors determine where you should locate the module in the I/O rack: 

ambient temperature and electrical noise. Consider the following conditions when selecting an I/O rack slot for the module. 

Position the module:

• in a slot away from ac or high voltage dc modules.

• away from the rack power supply if installed in a modular system.

• in the I/O rack lowest in the enclosure for a cooler ambient.

Determine the Module’s  Power Requirements 

Analog modules require power from the 5V dc and 24V dc backplane  power supplies of the SLC 500 system. 

This table shows the backplane  power requirements for fast analog I/O modules.

Minimize Electrical Noise Interference

Because high-speed analog signals are particularly vulnerable to electrical noise, take precautions when routing your signal cables. 

To help reduce the effects of electrical noise on analog signals, we recommend that you do the following:

• Install the SLC 500 system in a NEMA rated enclosure.

• Make sure that the SLC 500 system is properly grounded.

• Use Belden cable #8761 (or equivalent) for signal wiring.

• Ground the cable properly.

• Route signal cables away from other wiring or in grounded conduit.

• Group these modules away from ac or high-voltage dc modules.

We recommend re-checking system operation after installing new machinery or other sources of electrical noise near the system.