User Manual

LBI-38636S
12
ELECTRICAL CONNECTIONS
AC Power
The station will be received with the power cord
bundled and stored in the bottom of the cabinet. Remove
the twist tie from the AC power cord, unravel and feed the
cord through one of the rear cable holes. It may be helpful
to remove the grommet from the hole before passing the
cord through and reinstalling it afterwards.
A separate 15 to 20 Ampere, 120 Vac, 60 Hertz
electrical circuit should be provided for the station. A 120
volt grounded AC outlet for the station should be located
within six feet of the lower rear of the cabinet. The power
cord for the 120 Vac Power Supply comes with a
grounded 120 Vac molded plug attached. Check the
electrical code to ensure the power outlet complies with
local ordinances.
If a 240 Vac, 60 Hz source is used for the station, an
external step-down transformer (similar to 19C307148P1)
must be used.
For 230 Vac, 50 Hz applications, the station power
supply is equipped with a power cord, less connector, to
permit connection to an acceptable electric circuit. A plug
meeting local electrical codes must be supplied by the
customer. Make sure the station power supply is
connected to an outlet having the same configuration as
the plug. No adapters should be used in this configuration.
The equipment should be connected to a good earth
ground using a ground wire of adequate size. A ground
stud is provided for a separate cabinet ground. Use No. 14
or larger wire (depending on local ordinances and system
requirements) for connecting the cabinet to a good
building ground. After the ground lead from the power
cable is connected to the building ground, check for
continuity between building ground and the cabinet.
Microphone
The local microphone or utility handset may be
attached to the station through the MIC port on the front
of the T/R Shelf (Figure 6), the connections are shown in
Figure 5.
Antenna
The antenna cable may be routed through the top rear
or bottom rear of the cabinet directly to the appropriate
connector within the station, depending upon the
configuration.
TELEPHONE LINE CHARACTERISTICS
Telephone Lines
The type of telephone lines required for the
installation will depend on how the station is controlled
and if it is being used for simplex or duplex operation.
Generally, both 4-wire Audio and E & M Signaling
options are used to interface between the radio and carrier
systems. However, 2-wire Audio can be used in the two-
way radio portion of the control system if hybrids are
installed to provide transition between the 2-wire and 4-
wire connections. Usually the E & M Signaling is
separated from the audio (separate line) in both 2-wire
and 4-wire installations.
Figure 5 - Microphone Connections
Types Of Voice Grade Lines
Telephone lines are normally obtained from a
communications common carrier ("telephone company"
for our purposes here). When a voice grade (as contrasted
to a "data line") telephone line is requested, there is no
way of knowing just what type of line will be received
from the phone company.
In addition, the telephone company may supply one
type of line first, and later change it to another type
without any notification to the user. One of the following
types of telephone line can be expected:
1. Wire lines with no amplifiers
2. Wire lines with amplifiers added to compensate
for line loss
3. Facilities derived from carrier (multiplex)
These lines have different operating characteristics,
and each must be treated differently. In large systems, all
three types of lines can be provided. In long haul
applications, a system can consist of two or three of these
types of lines in tandem (tied together end-to-end).
The first type is WIRE LINE WITH NO
AMPLIFIERS. These are the same lines that have been
used for years to control dc systems. These are the easiest
to work with since they include no problem-causing
electronic equipment. These lines are normally found in