12.01.2021 Views

Speedfax 2017

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Low-voltage Switchgear<br />

Arc Flash Solutions<br />

General<br />

Under normal conditions, the switchgear’s calculated arc flash<br />

energy will require PPE level 3 protection for anyone within<br />

the arc flash boundary. Incorporating the features built into<br />

the DAS system, and using the ETU776 trip unit, the system<br />

changes to parameter set B. In the second figure the<br />

instantaneous has been changed to a lower setting and the<br />

calculation shows a reduction of arc flash energy. The<br />

resultant PPE level has been reduced to 0.<br />

Below is another example of the benefit of the DAS, or even<br />

manual switching, of breaker parameter set. The reduced<br />

settings set available in the ETU 776 can also be used to<br />

reduce the arc flash energy at downstream equipment. In the<br />

first figure on the left with normal settings the arc energy at<br />

panel 1 requires PPE level 2. After switching to the parameter<br />

B settings, the PPE level at Panel 1 is reduced to 0.<br />

Example 2<br />

SWGR 1<br />

WL 1600<br />

1600<br />

WL 800<br />

800<br />

PANEL 1<br />

PPE: 2<br />

AHE: 5.9 cal/cm^2(85%)<br />

AFB: 47.36 in<br />

WD: 17.9 in<br />

14 SWITCHGEAR<br />

Arc Flash in parameter A<br />

Arc Flash in parameter A<br />

Arc Flash in parameter B<br />

.01 .1 1 Time in Seconds 10 100 1000<br />

SWGR 1<br />

DLA: 1600<br />

Man.: SIEMENS<br />

Type: WLL<br />

Size: WLL 800A<br />

Trip: ETU 776 LSIG<br />

Max A/Plug/Setting: 800 / 800<br />

PANEL 1<br />

DLA: 1600<br />

Man.: SIEMENS<br />

Type: WLL<br />

Size: WLL 1600A<br />

Trip: ETU 776 LSIG<br />

Max A/Plug/Setting: 1600 / 1600<br />

.5 1 10 100 1000 10000<br />

Current in Amperes X 100<br />

480 Volt Phase Time-Current Characteristic Curves<br />

TCC 1<br />

SWGR 1 Main<br />

SIEMENS WLL ETU 776 LSIG<br />

WLL 1600A 1600 Amp<br />

800A FEEDER<br />

SIEMENS WLL ETU 776 LSIG<br />

WLL 800A 800 Amp<br />

03-31-2010<br />

11:42:04<br />

.01 .1 1 Time in Seconds 10 100 1000<br />

SWGR 1<br />

DLA: 1600<br />

Man.: SIEMENS<br />

Type: WLL<br />

Size: WLL 800A<br />

Trip: ETU 776 LSIG<br />

Max A/Plug/Setting: 800 / 800<br />

PANEL 1<br />

DLA: 1600<br />

Man.: SIEMENS<br />

Type: WLL<br />

Size: WLL 1600A<br />

Trip: ETU 776 LSIG<br />

Max A/Plug/Setting: 1600 / 1600<br />

.5 1 10 100 1000 10000<br />

Current in Amperes X 100<br />

480 Volt Phase Time-Current Characteristic Curves<br />

TCC 2<br />

SWGR 1 Main<br />

SIEMENS WLL ETU 776 LSIG<br />

WLL 1600A 1600 Amp<br />

800A FEEDER<br />

SIEMENS WLL ETU 776 LSIG<br />

WLL 800A 800 Amp<br />

03-31-2010<br />

09:34:42<br />

C:\EDSA2005\Projects\SAFETYSWITCHGEARWHITEPAPER.PDC<br />

C:\EDSA2005\Projects\SAFETYSWITCHGEARWHITEPAPER.PDC<br />

Siemens Industry, Inc. SPEEDFAX Product Catalog 14-91

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!