APC MW II manual Output and downstream breakers

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Output and downstream breakers

Q2, Q4, Q6

Duration [S]

Current [A]

Total load [%]

Event/Operation

 

 

 

 

< 0.005

22 kA

--

Internal fault clearing.

 

 

 

 

60

3464*

200

Overload on-line

 

 

 

 

600

2165*

125

Overload on-line

 

 

 

 

1732

100

On-line

 

 

 

 

* In the absence if a coordination study conducted by a professional engineer, the recommended

instantaneous trip setting for breakers Q1, Q2, Q4, Q5, and Q6 is 22 kA

** Only applicable to Q2 and Q4

In the absence of a proper breaker coordination study and if only the actual Ip on the unit’s input terminals is known, this table must be used to optimize the instantaneous trip setting or to choose a breaker with a usable fixed instantaneous trip value.

Ip* [kA]

I peak let-through [kA]

I setting [kA]

 

 

 

200

16

18

 

 

 

140

14

16

 

 

 

100

13

15

 

 

 

50

10.5

12

 

 

 

30

9

11

 

 

 

* Ip = Abridgment for Prospective short-circuit current.

This is the current that would flow in the fault circuit is the fuse was

replaced by a link with an infinitely small impedance

22 kA is the maximum peak let-through current (including safety factor) present during clearing of an internal fault in a 200 kW section or a power module. This maximum peak let-through current is based on and applicable to utility with prospective short-circuit currents (Ip) up to 200 kA.During or after a controlled fault clearing, none of the breakers are allowed to trip on the instantaneous trip setting below the specified value. This is also applicable to the upstream breakers, and a check of the instantaneous trip setting in this part of the installation is required.

The instantaneous trip setting calculated by a professional engineer in a breaker coordination study must not disable the functionality of clearing and surviving an internal fault unless there is a written agreement between APC by Schneider Electric and the customer.

By ensuring the unit’s fault clearing ability (survival skills) i.e. using the correct instantaneous trip settings in the switch gear (installation), maximum power availability in normal operation is obtained for the critical load.

Note: The instantaneous trip setting can be calculated when utility Ip is known. An incorrect trip setting can result in limiting the system functionality and jeopardize the load support.

Symmetra MW II 1200 kW 3 x 400/230 V Installation - 990-1979E-001

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Contents Installation Page Contents Specifications Installation safety Symbols used in this guidePage Serial number UPS SectionsInverter Section Control/Input/Output SectionExternal Bypass Static Switch Power wiring UPS Wiring PrincipleOverview Input/Output wiring precautions External disconnection switchesAC and PE cable connections  Hole distance AC Battery cables connection BAT1 + BAT2 External Bypass Static Switch Wiring Top cable entry Communication cable overview Maintenance Bypass PanelLocation of relay boards Relay BoardsCommunication cables with optional Relay Board Relay board 1 connections Relay Function Mode Special CommentsRelay board 2 connections Page Low-Impedance/High-Impedance Earthing Electrical SpecificationsDC Input AC InputAC Input External Bypass SSW AC OutputHeat dissipation Torque specifications Required Breaker Settings 400 V SystemsInput and upstream breakers Output and downstream breakers Dual Mains Installation System and Protective Earthing CharacteristicsTN Systems Reference to IEC 60364-4-41Protective devices in TN systems Additional requirements for generating sets IEC 60364-5-55Protective devices in TT systems TT SystemsIT Systems Protective devices in IT systems ConditionSee IEC Legal in DK specialcases Symmetra MW Switchgear Service Entrance Earthing arrangements and protective conductors Grounding Page Page 2009 990-1979E-001