PMP Synchronization Solutions User Guide
CMM Planning
PMP-0297 007v001 (January, 2017)
3-18
With PMP 54400 APs, the radio uses up to 12 W at 30 VDC and the input voltage as measured at
the "29 VDC" terminals on the CMM4 must be between 28 and 32 VDC to support 8 APs at the
maximum 100 m (328 ft) Ethernet cable length.
When supporting 56 VDC systems, the input voltage as measured at the “56 VDC” terminals on
the CMM4 must be between 44 and 59 VDC.
The CMM4 controller board provides two 20 VDC outputs – one for the EtherWAN switch, and one
optionally available for powering another low power device mounted in the enclosure by the
operator, such as a fiber-to-copper media converter. Total 20 VDC accessory power should not
exceed 20 W.
In cases where -48 VDC power is available and powering from the -48 VDC is desired (for example,
in some telecommunications huts), procure a -48 VDC to +56 VDC converter such as a Mean Well
Model SD-350C-48 and install between the -48 VDC source and the +56 VDC power supply.
EU Countries Only
To enable regulatory compliance with the European Union (EU) directives, a
power line filter module must be installed on the DC side of the power supply.
This module may be ordered from Cambium Networks (part number
N000000L056A). Please reference section
EU countries only – power line filter
Syncing Two Co-located CMMs Together
Two CMMs can be synced together to meet either of the following goals:
•
Case 1 – One GPS antenna for two CMMs: Use a single GPS antenna to support two CMMs.
This can be advantageous for a site with 2 CMMs where the site owner is charging per
antenna and the operator wishes to minimize site costs by only installing one GPS antenna.
•
Case 2 - Redundant Sync: Take advantage of co-located CMMs, each with its own antenna, to
provide “warm spare” redundant sync. If one GPS antenna, coax cable, or GPS module has
problems, remote re-configuration can re-establish sync to that CMM.
The CMMs can be any combination of CMMs - either two CMM4s, two CMMmicros, or a CMM4
and a CMMmicro.
Syncing two CMMs together requires connecting their RJ-11 auxiliary ports together with a 6-wire
cable and configuring each CMM appropriately. The location of the RJ-11 auxiliary port is shown
in
The connection cable is a special cable, not a straight-through cable. See page