Motorola PTP 400 Series - Manual (Page 139)

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9 Fault Finding
If communication has been lost with the unit at the near end of the link, there may be a
hardware fault with the wiring, network or hardware. Go to the hardware section below. If
communication with the far end of the link is lost then go to the radio section below.
9.1 Hardware
If there are problems suspected with the link hardware the following procedure is
recommended. The following diagram illustrates the main system connections.
Figure 74 - Main System Connections
9.1.1 Power
Check the power LED at each end of the link. If the power lights are illuminated go to the
Ethernet section below. If at either end they are not illuminated then 26 check the Ethernet
LED. If neither is illuminated then there is no voltage on the power wires to the ODU.
1. Check that the mains power is connected and switched on.
2. Check that the lamp illuminates if the ODU connector is disconnected at the PTP 400
Series Bridge PIDU Plus. (Remove the PIDU Plus cover).
a. If it does illuminate then either the ODU is drawing too much current, or the power
wiring to the ODU is short circuited or the PSU is supplying insufficient power. The
likely fault can be determined by removing the jumper (J905), found inside the
removable cover of the PIDU Plus, and measuring the current taken with an
ammeter placed across the 2 jumper pins. This is normally 10mA without the ODU
connected and 300mA to 1A when the ODU is connected.
26 The power indicator LED should be continually illuminated.