ePMP Powering at Sub-freezing Temperatures

ePMP Powering at Sub-freezing Temperatures

When operating ePMP equipment, it is crucial to make sure that enough voltage arrives at the device, even in very cold temperatures.

ePMP modules feature an integrated heating mechanism which operates (at startup only) until the unit temperature is greater than 32°F/ 0°C. While ePMP devices will power on at the lower end of their input power range, as temperatures change and the device heater is activated at startup, the device will consume additional power (the AP and SM will consume a steady 13 W during heater operation). In the case of a minimally-powered device, a drastic reduction in temperature can result in a non-powering unit (until proper voltage is restored).

An additional component of this planning is to ensure that proper steps are taken to compensate for voltage loss over long Ethernet runs. Verify that all power supplies, including third-party or CMM power supplies, are rated to provide enough voltage headroom.

Direct PoE Injection Notes for radio operation at sub 32°F/ 0°C temperatures:

  • For ePMP 1000 GPS Sync Radio and ePMP Force 110 PTP devices, the minimum voltage at the power supply source for a full 328 feet CAT5 cable run is 24.5 VDC (however, these radio can operate down to 23.5 V at up to 70 feet of cable).
  • For ePMP 1000 Connectorized Radio, Integrated Radio, and Force 180/200 devices, the minimum voltage at the power supply source for a full 328 feet CAT5 cable run is 22 VDC (however, these radios can operate at lower voltage with reduced cable length per the table below:

Voltage at Source

Maximum Cable Length

21

300

20

260

19

220

18

180

17

150

16

110

15

60

CMM Powering Notes for radio operation at sub 32°F/ 0°C temperatures:

  • For ePMP 1000 GPS Sync Radio and ePMP Force 110 PTP devices powered via CMM, the minimum voltage at the CMM power supply source for a full 328 feet CAT5 cable run is 25.5 VDC (however, these radios can operate down to 24.5 VDC at up to 70 feet.
  • For ePMP 1000 Connectorzied Radio, Integrated Radio, and Force 180/200 devices powered via CMM, the minimum voltage at the CMM power supply source for a full 328 feet CAT5 cable run is 23 VDC (however, these radios can operate at lower voltage with reduced cable length per the table below:

Voltage at Source

Maximum Cable Length

22

300

21

260

20

220

19

180

18

150

17

110

16

60

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