Telenetics Modular Nest manual Installing or Replacing a 326X Backplane, Pin Description

	Part No. TEL–09949, Rev A
Removing and Installing a Backplane in Modular Nest 9 or 21 Enclosure	June 2001
	Page 30 of 34

Installing or Replacing a 326X Backplane

Caution

Power down the unit before you begin.

To install or replace a backplane in a Modular Nest 9 or 21 enclosure (Figure 14):

1)Ensure the enclosure is powered down.

2)Using the alignment guides on the backplane and enclosure to line up the backplane between the screw holes on the top and bottom of the enclosure, first insert the bottom of the backplane (A), and then rotate the top of the backplane into position (B). Do not to bend any pins on the connector.

3)Push down slightly on the base of the backplane (C), ensuring that the backplane connectors are aligned.

4)Using a flat-blade screwdriver, secure the backplane to the enclosure with the fasteners supplied. Fasten the base first, then the top.

5)Remove all cards and power supplies from the front of the enclosure.

6)Set an Ohm-meter a minimum 20 Ω range. Measure the resistance between the following pairs of J2 test-connector pins:

Pin	Description	Pin	Description
1	Digital ground	4	+5V
1	Digital ground	5	+12V
1	Digital ground	6	-12V
4	+5V to	5	+ +12V
4	+5V	6	-12V
5	+12V	6	-12V

•If all readings register as open circuits, the backplane connectors are not short-circuited. Go on to the next step.

•If any reading registers resistance, the backplane connectors are short- circuited. Remove the backplane (using the procedure above), and carefully straighten any bent or broken pins. Reinsert the backplane (using this procedure).

If you cannot resolve a problem, call the Telenetics Customer Support

Center.

7)Re-install the cards and power supplies that were removed when you removed the backplane.

8)Power up the enclosure.