Page 114 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

Symptom Specification

Rating 600 VA
Input Voltage 150V AC to 275 V AC
Output Voltage 220V AC- Nominal

Protection (input fuse) Provided
DC Input 12 V
Battery Type Sealed lead-acid
Battery recharge time 8 hours (up to 90%of full capacity)
Battery Capacity 12V 7AH

Power Range of UPS:
UPS are made in following three power ranges.

Low Power Range – up to 1000 VA
Medium Power Range – up to 10 KVA
High Power Range – above 10 KVA
Selection Of UPS:
When selecting an uninterruptible power system, engineers must consider the following factors that can make or
break the success of the system.
Load Size: The Size of the critical load determine the capacity of the initial installation. The UPS must have
adequate capacity to reliably serve the critical load and additional loads, without immediate expansion.
Input Voltage: The input voltage available at the site and fluctuations occur generally.
Output Power Range: The total wattage of the load to be connected to the UPS.
Battery Run Time: The battery run time of a UPS is the length of time the UPS can reliably supply power to the
critical load after input power has failed. Run time usually is defined as the length of time required for connecting
data-processing equipment to save data files and shut down in an orderly fashion, along with a margin of safety.
Typically, Battery run time is 15 min. Hence, someone must review the proposed installation to determine if
modification is necessary to support the load.
Changeover Period: Changeover period should be less than 1 us for computers.
Indicator Used:
1 Power on Indicator: This LED indicates whether the UPS unit is powered on and receiving electricity from an
external power source.
2 Battery Status Indicator: This LED provides information on the charge level of the UPS’s internal battery. It
helps users determine whether the battery is fully charged or if it needs to be recharged.

3 Load Capacity Indicator: The load capacity indicator helps users gauge the amount of power being drawn
from the UPS. It indicates whether the load is within acceptable limits or if it is approaching or exceeding the
UPS’s capacity.
4 Fault or Alarm Indicator: This LED is crucial for identifying any faults or alarms that the UPS has encountered.
It can signal issues such as overload, battery failure, or any other problems that require immediate attention.
Protection Required:
UPS components include a rectifier, ups battery, an inverter and a static switch. Within a modern system these are
usually set up in an online configuration. This means that during normal operation the incoming mains feeds the
rectifier which in turn supplies the inverter with a stable DC voltage as well as float-charging the battery.
If the mains supply transgresses acceptable limits, power to the inverter is provided by the battery until either
normal main is restored or the battery is exhausted. As the battery nears exhaustion, the static switch can be used
to transfer the load to a bypass supply.

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CITS : E & H - Electronics Mechanic - Lesson 56 - 63