To apply -48 volt dc power to the Access-T, perform the following steps:
1.
Remove the three-slot black plug from connector TB1 on the Access-T
rear panel. (Contact Larscom if this plug has been lost.)
2.
Using #14 AWG (minimum) wire, connect the -48 volt dc power,
return, and ground leads to the plug as illustrated in Figure 3-3. To
make a wiring connection to the plug:
a.
Turn the screw corresponding to the desired wire slot counter-
clockwise until the slot accepts the wire.
b.
Insert the wire into the slot.
c.
Turn the screw clockwise until the wire is held firmly.
3.
Insert the plug into the TB1 connector on the Access-T rear panel.
4.
Install the retaining bracket for the power plug using the 4-40 pan-
head Phillips screw and flat washer provided. This retainer prevents
accidental removal of the power plug, per UL specifications.
Fuse
DC-powered Access-T 100/200/400 units provide overcurrent protection with
a Slo-Blo fuse. The fuse is mounted in the rear panel. The Access-T Series 400
uses a 2 amp fuse (part number 250-110-50); the Access-T Series 100 or 200 uses
a 1 amp fuse (part number (250-110-90). If the fuse blows, insert a new one, as
described in Chapter 9.
If the fuse blows continuously, there is a problem either in the power source or
in the Access-T internal power supply.
Figure 3-3. DC Power Connections
1
2
3
TB1
-48 V dc Battery
Battery Return (+)
Earth Ground
Chapter 3
ACST-0351-005
Installation
June 1996
3-8