User Manual

AS4000 Access Concentrator
Installation and Commissioning
DLP 003
605-0000-453
Issue 1.2dr Date 7/02/00
Page 3 of 8
2. Rack Earthing
Using the site survey, locate the building central [safety] grounding point. Run an
earth cable rated at 30A to each rack and connect it to the centre earth stud located at
the top or bottom (not both) of the rack. See Figure 7. These points are labelled with
the IEC Earth symbol. .
Earthing Point
Rack Base
Earthing Point
Figure 7. Rack Earthing
Warning: Other external safety earth connections must not be made to the
rack. The two studs located towards the sides at the top of the rack are used
for earth bonding the side and rear panels to the rack and must be left
untouched to maintain the systems safety earthing integrity.
Terminate the battery feed and return cables at the isolator/fuse positions, and ensure
that the AC rack is isolated until the commencement of commissioning tests.
3. Alarm Unit (Type 55B) External Connections
Run alarm cables from the station alarm scheme to the AU55B in the Fuse and Alarm
Panel in the AC Rack. Terminate on the 25 way D-Type connector as shown in Figure
8 and to the station alarm scheme. Connect the -48V/24V alarm supply to the alarm
supply fuse box using 1.0mm cable and terminate on the D-type connector.