User's Manual

Table Of Contents

26 3. Installation

3.8.3Grounding the SDIDU

1. The SDIDU™ should be able to be connected to a system or building electrical ground

point (rack ground or power third-wire ground) with a cable of 36” or less.

2. Connect the grounding wire to either grounding point on the rear panel. Use

6-32x5/16 maximum length screws (not provided) to fasten the lug of the grounding

cable.

3. Connect the other end of the ground to the local source of ground in an appropriate

manner.

3.8.4Connecting the SDIDU

to the PC and Power Source

1. Using the supplied power cable connector, pin 2 (labeled -V) should be connected to the

power supply terminal supplying -48 V dc, while pin 1 (labeled RET) should be connected to

the power supply return. Refer to Figure 3-17. Use of a power supply with an inappropriate

ground reference may cause damage to the SDIDU

and/or the supply.

Figure 3-17. SDIDU DC Power Cable Connector

2. Connect the SDIDU

power cable to the 48 V dc power supply, and place the

voltmeter probes on the unconnected SDIDU

end of the power cable, with the

positive voltmeter probe on pin 2 (-V) of the cable connector and the negative probe

on pin 1(RET). The connector terminal screw heads may be used as convenient

monitor points. Refer to Figure 3-17.

3. Turn on the –48 V dc supply. Verify that the digital voltmeter reads between 44 V dc

and 52 V dc when monitoring the cable points specified above. Adjust the power

supply output voltage and/or change the connections at the power supply to achieve

this reading.

4. Turn the 48 V dc supply off.

5. Plug the SDIDU

power cable into the SDIDU

rear panel DC Power connector (DC

Input). Place the voltmeter probes on the cable connector terminal screw heads as