Service Current Rating; Table 3-4 Typical Power Loads And Heat Dissipation Values - Mts Uhf Configurations - Motorola DIMETRA MTS 2 Installation, Configuration And Basic Service Manual

Service Current Rating

Service Current Rating
The input current rating of the DC power supply equipment shall be considered
when selecting the AC main service.
The DC power system has normal loads and start-up loads. These loads are dependent on the number
of Base Radios in the site and the size and condition of the backup battery system. The normal
load of a typical power system is provided in
using battery backup.
Cabinets. These loads may differ for the customer designed power systems.
Table 3-4 Typical Power Loads and Heat Dissipation Values - MTS UHF Configurations
MTS UHF
Configuration
TETRA TX 10 W
MTS2 with 1 BR
MTS2 with 1 BR w.
Hybrid
MTS2 with 2 BRs
MTS2 with 2 BRs w.
Hybrid
MTS4 with 1 BR w.
MTCC/ATCC
MTS4 with 2 BRs w.
MTCC/ATCC
3-16
rated min. 20 A/55 VDC should be introduced. And for the MTS4, two of these
units should be used, one for each of the two incoming DC lines. Alternatively
for the MTS4, one relay rated 40 A/55 VDC can be used if the two DC lines are
connected to one battery pack. The relays should be controlled in a way that they
disconnect the batteries once the voltage drops below 40.5 V, where the PSU in
the MTS shuts down. Two Motorola kits are available for this purpose:
• MTS2 LVD RELAY RETROFIT KIT (Kit Number: GMDN2206A)
• MTS4 LVD RELAY RETROFIT KIT (Kit Number: GMDN2207A)
The battery installation need a short circuit protection closest to the batteries.
The batteries should be installed in the same building and properly ventilated.
Table 3-5 lists typical power loads and heat dissipation values for Expansion
Heat
AC AC
(W) (W)
140 130
165 155
245 225
295 275
240 230
375 355
Table 3-4 for several common MTS configurations
AC Heat AC
When When
Charg- Charging
ing (W)
(W)
520 185
545 210
625 280
675 330
625 290
755 410
Chapter 3: Site Preparation
DC Heat
-48 V DC
(W) (W) Comment
135 125 No combining, low
power PA, no fans
160 150 Low power PA, no
fans
240 220 Two TX ant., low
power PA, no fans
285 265 Low power PA, no
fans
235 225 Low power PA,
fans
365 345 Low power PA,
fans
6802800U74-N September 2009