Lynx.GX Installation and Management
Be sure to connect the return to ground at the DC power plug and make sure that all equipment is grounded to
proper station earth ground.
Negative DC Power Input Pin Assignment (-
20 to -63 VDC)
Pin Number
Function
1
Power (–DC)
2 Ground
3
Return (+DC)
Positive DC Power Input Pin Assignment
(+20 to +63 VDC)
Pin Number
Function
1
Return (–DC)
2 Ground
3
Power (+DC)
Note:
Each radio terminal block must be fused externally with an 5-Amp maximum fuse. The DC power cable
must be shorter than 3 meters (9.75 feet).
To wire the DC power, wire the power cable with an adequate current rating into the terminal block connector
using the screw connections on the terminal block.
Suggested rating of external fuses and cables is 5 to 8 Amps (-120W to –240W) for 24V and 3 to 5 Amps (-144
W to –240 W) for 48V in order to accommodate inrush current at equipment power-up.
The radios consume less than 1.5 Amp at + 48V, less than 3.0 Amp at + 24V under steady-state conditions.
▪
If using
negative power
, connect the negative voltage to pin
1
. Connect the return connection to pin
3
and
use an optional jumper to pin
2
for ground reference.
▪
If using
positive power
, connect the positive voltage to pin
3
. Connect the return connection to pin
1
and
use an optional jumper to pin
2
for ground reference.
The ground connection is available using pin
2
.
Do not ground both sides of the power supply
.
Proxim recommends you leave the ground connection floating if the power supply also is floating. This
configuration can help avoid ground loops and provide the best lightning protection; however, if the power
source is referenced to ground, this configuration may not provide adequate grounding for lightning protection.
This configuration is more susceptible to lightning damage no matter what grounding scheme for the radio
power supply is chosen.
A grounding screw and nut is provided on the left front panel of the IDU. Be sure to use the local electrical code
to determine wire size and proper connection to the grounding screw, and do not depend on rack mounting
screws for a ground connection.
Note:
Proper grounding, either through the chassis or the power supply, is important for protecting the unit
against lightning. A grounding screw post is provided on the front panel.
Use a digital voltmeter (DVM) to verify the voltage and polarity of the plug after wiring the terminal block for
power and before inserting the plug into the IDU.
Chapter 2. Installing the IDU and RFU
26
