Siemens 7SR242 Duobias - Elements

7SR242 Duobias Commissioning & Maintenance Guide
©2010 Siemens Protection Devices Limited Chapter 6 Page 35 of 57
Apply 0.5x setting current and record operating time
Phase Is
(Amps)
DTL
(sec)
P.U. Current
Amps
Operate Time
0.5 x Is
NOTES
Wn-I
L1
(I
A
)
Wn-I
L2
(I
B
)
Wn-I
L3
(I
C
)
Wn-I
L1
(I
A
)
Wn-I
L2
(I
B
)
Wn-I
L3
(I
C
)
Elements can be blocked by operation of a Binary Input Inhibit or by operation of the 37-n U/I Guard element.
This functionality should be checked.
Element BI Inhibits U/I Guard NOTES
37-1
37-2
Check correct indication, trip output, alarm contacts, waveform record.
2.7.2 37G-n Elements
Apply current to the I
Gn
input at a level above the 37G-n setting until the element resets.
If DTL setting is small, gradually reduce current until element operates.
If DTL is large apply 1.1x setting, check for no operation, apply 0.9x setting, check operation
Apply 0.5x setting current and record operating time
Phase Is
(Amps)
DTL
(sec)
P.U. Current
Amps
Operate Time
0.5 x Is
NOTES
I
G
I
G
Elements can be blocked by operation of a Binary Input Inhibit.
This functionality should be checked.
Element BI Inhibits NOTES
37G-1
37G-2
Check correct indication, trip output, alarm contacts, waveform record.