Ac And Dc Power Supplies; Service Current Rating - Motorola MTS LiTE Installation, Configuration And Basic Service Manual

• UK - RPSG Installation Manual, System Quality Standard, specification number 2200 and part
number. 68P02200F01.
• UK - Institution of Engineering and Technology (IET) - BS 7671:2001 16th Edition Wiring
Regulations (Appendix 12, Cable Capacities of Conduit and Trunking).
• UK - Antenna System Installation Practice, issued by The Directorate of Telecommunications of the
UK Home Office.
• UK - Details of Earthing Requirements for Masts, Aerial Feeder Cables, and Radio Equipment
Rooms, issued by The Directorate of Telecommunications of the UK Home Office.
• GERMANY - VDE0100 Errichten von Starkstromanlagen bis 1000 Volt.
• GERMANY - VDE0185 Blitzschutzanlagen.
• GERMANY - VDE0510 Akkumulatoren und Batterieanlagen.
• GERMANY - VDE0855 Antennenanlagen, Errichtung und Betrieb.
3.7.2

AC and DC Power Supplies

The MTS cabinet is equipped with a high efficiency switch mode Power Supply Unit (PSU).
Operating modes are as follows:
• DC only operation (within -41 VDC to -60 VDC)
• AC only operation (within 90 VAC to 264 VAC; 45 Hz to 66 Hz)
• AC operation (within 90 VAC to 264 VAC; 45 Hz to 66 Hz) and switch over to DC backup operation
when AC failed
The PSU handles the automatic switch over to a backup battery in the event of AC mains failure.
CAUTION: An external disconnect device and appropriate 20A fuse are required on the DC
power supply line.
CAUTION: If the DC input on the station is connected to back up batteries, an external Low
Voltage Disconnect (LVD) device should be introduced directly in the power line in order to
protect the batteries against deep discharge. On the MTS 2, one relay rated min. 20 A/55 VDC
should be introduced. And for the MTS 4, two of these units should be used, one for each of the
two incoming DC lines. Alternatively for the MTS 4, 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 Solutions kits are available for this purpose:
• MTS2 LVD RELAY RETROFIT KIT (Kit Number: GMDN2206A)
• MTS4 LVD RELAY RETROFIT KIT (Kit Number: GMDN2207A)
CAUTION: The battery installation need a short circuit protection closest to the batteries.
IMPORTANT: The batteries should be installed in the same building and properly ventilated.
3.7.2.1

Service Current Rating

When selecting the AC main service, consider the input current rating of the DC power supply
equipment.
6802800U74-AN
Chapter 3: Site Preparation
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