SPRAM style provides the most compact construction due to diagonal bushing arrangements with a 6-1/2" phase spacing. These models can accommodate bushing mounted fuses. SPRAM style switches are available in rotary puffer (RP) and linear puffer (PI) designs.
Load break switch (RP module) ratings
Maximum design voltage
15.5 kV
27 kV
Voltage class
15 kV
25 kV
Impulse level (BIL)
110 kV
125 kV
One minute withstand
35 AC kV
60 AC kV
One minute withstand, production test rating
34 AC kV
40 AC kV
15 minute withstand
53 DC kV
78 DC kV
Continuous and load break current
630 Amps
Momentary current
25.6 kA asym
20 kA asym
Fault close current, (3 times)
One second current
16 kA asym
12.5 kA asym
Operations load interrupting endurance (15kV) at 600A
500
350
Mechanical endurance, operations
2000
Load break switch (PI module) ratings
38 kV
35 kV
150 kV
One minute withstand,
70 AC kV
One minute withstand, Production test rating
50 AC kV
103 DC kV
40 kA asym
Fault-close current, (3 times)
25 kA sym
Open gap withstand
200 kV
10 operation overload interrupting capability
3000 Amps
Operations load interrupting at 600a
1200
