Introduction (cont.)

Isolation and protection devices

UPS or converter cubicles

(figure 8)

Q1 (switch):

isolation from Mains 1,

RC start-up;

QF1 (circuit breaker):

battery protection and isolation;

Q5N (switch):

isolation of the inverter, frequency converter or static switch module from the load;

Q4S (switch):

isolation of the static switch from Mains 2;

Q3BP (switch):

bypass switch for maintenance;

FU1-2-3 (fuses):

protection of the RC from Mains 1;

FU5-6-7 (fuses):

protection of the inverter from the load.

Note:

switches Q4S and Q3BP do not exist on frequency converters,

circuit breaker QF1 does not exist on frequency converters without a battery.

Example of a single-unit UPS or single modular UPS

Q3BP

 

 

 

 

 

Q4S

static switch

mains 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

rectifier-

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

inverter

 

 

 

charger

 

 

 

 

 

Q1

 

 

 

 

 

 

 

 

 

 

 

Q5N

 

 

 

 

 

 

 

 

 

 

 

mains 1

 

 

 

 

 

 

 

 

 

 

 

 

 

load

FU1-2-3

 

 

QF1

 

 

 

FU5-6-7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

battery

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig. 8

Static Switch Cubicle

 

 

 

 

 

 

 

 

 

(figure 9)

 

 

 

 

 

 

 

 

Q3BP

Q4S (switch):

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

isolation of the static switch (and

 

 

 

 

 

 

 

 

 

mechanical contactor K2S) from

 

 

static switch

Mains 2;

 

 

 

 

Q4S

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Q3BP (switch):

mains 2

 

 

 

 

 

 

 

bypass switch for maintenance;

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Q5N (switch):

 

 

 

 

 

 

 

 

 

isolation of the load from the parallel

 

 

 

 

 

 

 

 

Q5N

UPSs;

parallel

 

 

 

 

 

 

 

 

 

 

 

 

 

 

load

Q1 (fuse switch):

UPSs

 

 

 

 

 

 

 

protection of the cubicle control

 

Q2

 

 

 

 

 

 

 

electronics from the parallel-connected

 

Q1

 

control

inverter outputs;

 

 

 

electronics

 

 

 

 

 

 

 

 

 

Q2 (fuse switch):

protection of the cubicle control

electronics from Mains 2.

Fig. 9

 

 

External maintenance bypass cubicle (figure 10)

Q3BP (switch):

bypass switch for maintenance;

Q5N (switch):

isolation of the load from the parallel- connected UPSs.

Q3BP

maintenance bypass line

 

Q5N

parallel

load

modular UPSs

 

Fig. 10

Page 8 - 6739380EN/JC

Page 8
Image 8
APC 6739380EN/JC user manual Isolation and protection devices, UPS or converter cubicles, Static Switch Cubicle