Deploying PMP 450 with CMM

To ensure that a CMM-based AP cluster deployment functions properly, it is essential to plan CMM powering and cabling to provide enough voltage to each AP device. Using a third-party power supply may result in disruption in AP operation and service outages.

Powering the CMM (and connected APs)

It is highly recommended to utilize Cambium Networks 30 VDC or 54 VDC supplies to power CMM units. These power supplies have been thoroughly tested to provide proper voltage to Cambium Networks APs.

A 30 VDC CMM power supply is used with the following equipment:

  • All PMP 450 Access Points - 2.4, 3.5, 3.65 or 5 GHz

A 54 VDC CMM power supply must be used for the following equipment:

  • 5 GHz PMP 450i Access Points
  • 900 MHz PMP 450i Access Points

Power supply part numbers

Name

Part Number

 
 

30 VDC Power Supply

(no cables or cords)

N000000L055A

 CMM_power_supply.png

54 VDC Power Supply

(no cables or cords)

N000000L054A

 
CMM_power_supply.png

A Note about CMM Power Blocks

There are four input power terminal blocks inside the CMM4. Two of them are for 29/30 VDC input, and the other two are for 56 VDC input. The two 29 VDC terminal blocks and the two 56 VDC terminal blocks allow the CMM4 to be powered from redundant power supplies, if so desired.

The 30 VDC CMM4 power supply is labeled as 30 VDC and typically measures 30 VDC at its output. The associated CMM4 terminal blocks are marked 29 VDC, and some associated SM power supplies are labeled 29.5 VDC. All of these components are elements of a nominal 30 VDC system, and can be considered “30 VDC” elements.

The 54 VDC CMM4 power supply is labeled as 54 VDC and typically measures 54 VDC at its output. The associated CMM4 terminal blocks are marked 56 VDC, and associated SM power supplies are labeled 56 VDC. All of these components are elements of a nominal 56 VDC system, and can be considered “56 VDC” elements.

If you are using a CMM4 to power both 30 VDC and 56 VDC systems, then you must install both 30 VDC and 54 VDC power supplies along with the CMM4. These power supplies must be wired to the correct terminal blocks (marked 29 VDC and 56 VDC).

Cabling the CMM

DC Cables

Cambium recommends the use of flame-retardant, moisture and sunlight-resistant cable rated to 75° C wet and bendable at -25° C for the DC cable between the power supply(s) and the CMM4. Examples of such cable include General Cable (http://www.generalcable.com), catalog number 234580 for 12 AWG cable and catalog number 236300 for 10 AWG cable, found in the Telecommunications Catalog.

Recommended wire size for the CMM4’s DC cable in most systems is shown below. These wire sizes support up to 8 radios (30 VDC or 56 VDC radios) at up to 100 m (328 ft) Ethernet cable length from the CMM4.

Wire size for CMM4 DC cable

DC Power Cord Length

Wire Gauge

Under 12 ft (12.6 m)

14 AWG (2 mm2)

12 - 90 ft (3−25 m)

12 AWG (4 mm2)

91−145 ft (26−45 m)

10 AWG (6 mm2)

146−230 ft (46−70 m)

8 AWG (10 mm2)

 Ethernet Cables

The operator provides the Ethernet cables between the CMM4 and the radios it supports. They must be engineered to length and are not included with the CMM4. The cable length from the CMM4 to any radio must be under 100 m (328 ft). Shielded cables are highly recommended for all installations.

Cables are available from Best-Tronics, Inc., http://best-tronics.com/. These cables can be ordered in lengths up to 328 ft (100 m) and are listed below:

Recommended Ethernet cables

Typical Use

Best-Tronics
Part #

Description

Infrastructure Ethernet cable

BT-0781S-XXX

RJ-45 to RJ-45 straight, shielded, UV-resistant Ethernet cable using outdoor STP Cat 5e cable, lower cost than plenum-rated, available only in black.

Infrastructure Ethernet cable for plenums

BT-0562S-XXX

RJ-45 to RJ-45 straight, shielded, UV-resistant, plenum-rated Ethernet cable using outdoor STP Cat 5e cable, available in beige, blue, grey, or white.

(Thanks to Marty Gray for providing the basis for this article)