Annex 3 - Uninterruptable Power Supplies (UPS)
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Statutory Documents - IMO Publications and Documents - Circulars - Radiocommunication and Search and Rescue - COMSAR/Circ.16 - Guidelines on the Configuration of the Reserve Source or Sources of Energy Used to Supply Radio Installations on GMDSS Ships - (4 March 1998) - Annex 3 - Uninterruptable Power Supplies (UPS)

Annex 3 - Uninterruptable Power Supplies (UPS)


The UPS should meet the general requirements set out in regulation IV/13 of SOLAS 1974, as amended, and in resolution A.694(17), as applicable, and should also comply with the following requirements.


2.1 An uninterruptable power supply system (UPS) is defined as a device which for a specific period of time supplies continuous power to radio equipment independent of any power failures in the ship's main or emergency source of electric energy.

2.2 The UPS should comprise at least:

  • .1 an automatic charger, complying with the requirements of paragraph 4.5 of these guidelines and of annex 2; and

  • .2 rechargeable accumulator batteries, complying with the requirements of annex 1.


Provisions should be made for an aural alarm and visual indication at the position from which the ship is normally navigated, indicating any failure in the UPS which is not already monitored by the alarm and indicators required by paragraph 5 of these guidelines and by annex 2.


The UPS should be operational within 5 s of switching on.


The UPS should be so designed and constructed that it is protected against damage resulting from disconnecting the batteries or, with the battery disconnected, short-circuiting the UPS battery connections. If this protection is provided by electronic means it should automatically reset following removal of the open or short-circuit conditions.

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